Expansion joint and its installation method

Abstract

To provide an expansion joint capable of improving durability, and a method of installing the expansion joint to a joint part between a vibration sieve and a duct.SOLUTION: An expansion joint 10 is equipped with an inner cylinder 100, and a cylindrical piping member 101 that is disposed outside the inner cylinder 100 and has a layer structure of a single layer or a plurality of layers. The outermost layer of the piping member 101 is formed by a material that is included in a range of hardness 30Hs to 55Hs, is included in a range of tensile strength 5 MPa to 20 MPa, is included in a range of elongation percentage 400% to 1000%, and is included in a range of tearing strength 10 kN / m to 100 kN / m.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an expansion joint to be installed at the joint between a vibrating screen and a duct used in a thermal power plant and / or a garbage disposal plant, etc., and to a method for installing the same. [Background technology]

[0002] Conventionally, expansion joints are provided at the connection parts of ducts that transport fluids such as exhaust gas discharged from combustion equipment in thermal power plants, steelworks, waste incinerators, etc., to absorb thermal expansion and vibration of the ducts. The expansion joint disclosed in Patent Document 1 includes a pair of flanges connected to ducts on both sides of the expansion joint, respectively, and a plurality of laminated insulating members. The insulating members are formed to a length equivalent to the circumferential length of the flanges, and are attached in a cylindrical shape along the circumferential direction of the flanges between the pair of flanges of the expansion joint, surrounding the entire circumference of the flow path.

[0003] Patent Document 2 discloses a flexible pipe joint that includes a flexible piping member, a pipe body that covers an outer skin layer of the piping member and has an elastic part with tough fibers embedded therein, and a pair of flanges provided on both ends of the pipe body. The piping member has a convex part that protrudes in a direction perpendicular to the axial direction of the piping member and a concave part that is concave in the opposite direction to the convex part, and the concave part is filled with an elastic material that is softer than the elastic part. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-150561 A [Patent Document 2] Patent No. 5236936 Summary of the Invention [Problem to be solved by the invention]

[0005] The expansion joint for the vibrating sieve, which is installed at the joint between the vibrating sieve and the duct, is exposed to vibration and large displacement caused by the vibrating sieve for a long time, and therefore frequently suffers damage and has an extremely short lifespan. For example, when a bellows pipe having a convex part protruding in a direction perpendicular to the axial direction of the bellows pipe and a concave part recessed in the opposite direction to the convex part as described in Patent Document 2 is used for the expansion joint for the vibrating sieve, it may break at the concave part. In addition, if the material of the outermost sealing layer of the piping member is weak or has poor flexibility, the bellows pipe is manufactured with an extra length, and therefore wrinkles are generated on the surface of the bellows pipe when it is subjected to vibration for a long time, and the wrinkled part tends to be damaged by bending and wearing.

[0006] The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide an expansion joint and an installation method thereof that can improve durability. [Means for solving the problem]

[0007] One aspect of the present invention is an expansion joint to be installed at the joint between a vibrating screen and a duct, comprising an inner tube and a tubular piping member arranged on the outside of the inner tube and having a single-layer or multiple-layer structure, characterized in that the outermost layer of the piping member is formed from a material having a hardness in the range of 30Hs to 55Hs, a tensile strength in the range of 5MPa to 20MPa, an elongation in the range of 400% to 1000%, and a tear strength in the range of 10kN / m to 100kN / m.

[0008] In the expansion joint of the present invention, the piping member is configured by laminating an inner skin layer, an elastic layer, and an outermost seal layer in that order from the inside, and the outermost seal layer may be formed from a material having a hardness in the range of 30Hs to 55Hs, a tensile strength in the range of 5MPa to 20MPa, an elongation in the range of 400% to 1000%, and a tear strength in the range of 10kN / m to 100kN / m.

[0009] The expansion joint of the present invention may further include a pair of flanges installed at both ends in the central axial direction of the piping member and fixed to the vibrating sieve and the duct, respectively, and the inner tube may be fixed to each of the pair of flanges and composed of a first inner tube portion and a second inner tube portion which are relatively displaceable, and the first inner tube portion and the second inner tube portion may be arranged so as to partially oppose each other in a direction perpendicular to the central axial direction of the expansion joint.

[0010] In the expansion joint of the present invention, the outermost sealing layer may be formed from a material having a hardness in the range of 30Hs to 45Hs, a tensile strength in the range of 10MPa to 20MPa, an elongation in the range of 600% to 800%, and a tear strength in the range of 45kN / m to 65kN / m.

[0011] In the expansion joint of the present invention, the first inner cylindrical portion may have a shape such that the diameter gradually decreases from one end to a middle portion in the direction of the central axis of the piping member, and then the diameter remains constant from the middle portion to the other end, and the second inner cylindrical portion may have a shape such that the diameter is constant along the central axis of the piping member.

[0012] The expansion joint of the present invention has a pair of fixing members for fixing both ends in the central axial direction of the piping member to the vibrating sieve and the duct, respectively, and each fixing member may have a fixing portion for fixing the end of the piping member, and a protruding portion that protrudes radially outward from the fixing portion while bending or curving in a direction approaching the opposing fixing member.

[0013] In the expansion joint of the present invention, a fixing frame is provided for fixing the other end in the central axial direction of the piping member to the duct, and the fixing frame may have a communication hole formed therein that communicates with the gap between the inner tube and the piping member.

[0014] Another aspect of the present invention is a method for installing an expansion joint at a junction between a vibrating sieve and a duct, comprising the steps of: fixing the expansion joint, fabricated to have a first designated length in the direction of the central axis, to the vibrating sieve and the duct, respectively, by each of the pair of flanges; applying a force between the pair of flanges so that the expansion joint is maintained in a state stretched to a second designated length that is longer than the first designated length; and releasing the force from the pair of flanges, wherein after the step of releasing the force, the state of the expansion joint changes from the second designated length to a third designated length that is at least longer than the first designated length.

[0015] The method for installing an expansion joint of the present invention may include the steps of fixing the expansion joint, fabricated to have a first designated length in the central axis direction, to the vibrating sieve and the duct, respectively, by each of the pair of flanges; applying a force between the pair of flanges so that the expansion joint is maintained in a state stretched to a second designated length that is longer than the first designated length; and releasing the force from the pair of flanges, and may also include a state in which, after the step of releasing the force, the state of the expansion joint changes from the second designated length to a third designated length that is at least longer than the first designated length.

[0016] In the method for installing an expansion joint of the present invention, the first specified length may be 50% to 100% of a length calculated by subtracting a vibration amplitude of the vibrating sieve from the second specified length. Effect of the Invention

[0017] According to the expansion joint of the present invention, wrinkles are less likely to form in the outermost layer of the piping component, thereby improving the durability of the expansion joint against long-term vibration when installed at the joint between a vibrating screen and a duct. [Brief description of the drawings]

[0018] [Figure 1]FIG. 1 shows an expansion joint according to the present invention, and is an explanatory diagram of the configuration of a first embodiment thereof. [Diagram 2] FIG. 2 is a schematic explanatory diagram showing an example of a vibrating sieve in which the expansion joint is installed. [Figure 3A] FIG. 2 is an explanatory diagram of the configuration during manufacturing of the expansion joint. [Figure 3B] FIG. 2 is a configuration explanatory diagram of the expansion joint when installed. [Figure 4] FIG. 13 is a configuration explanatory diagram of an expansion joint according to a comparative example when installed. [Diagram 5] FIG. 13 is a configuration explanatory diagram of an expansion joint according to a comparative example when installed. [Figure 6] FIG. 13 is a configuration explanatory diagram of an expansion joint according to a comparative example when installed. [Figure 7] FIG. 13 is a configuration explanatory diagram of an expansion joint according to a comparative example when installed. [Figure 8] FIG. 13 is a configuration explanatory diagram of an expansion joint according to a comparative example when installed. [Figure 9] FIG. 2 is a configuration explanatory diagram of a second embodiment of an expansion joint according to the present invention. [Figure 10] FIG. 4 is a configuration explanatory diagram showing a first modified example of the expansion joint of the embodiment. [Figure 11] FIG. 11 is a configuration explanatory diagram showing a second modified example of the expansion joint of the embodiment. [Figure 12] FIG. 11 is a configuration explanatory diagram showing a third modified example of the expansion joint of the embodiment. [Figure 13] FIG. 4 is a configuration explanatory diagram of a third embodiment of an expansion joint according to the present invention. [Figure 14] FIG. 4 is a configuration explanatory diagram showing a first modified example of the expansion joint of the embodiment. [Figure 15] FIG. 11 is a configuration explanatory diagram showing a second modified example of the expansion joint of the embodiment. [Figure 16] FIG. 11 is a configuration explanatory diagram showing a third modified example of the expansion joint of the embodiment. [Figure 17] FIG. 11 is a configuration explanatory diagram of a fourth embodiment of an expansion joint according to the present invention. [Figure 18]FIG. 11 is a configuration explanatory diagram of a fifth embodiment of an expansion joint according to the present invention. [Figure 19] FIG. 11 is a configuration explanatory diagram of a sixth embodiment of an expansion joint according to the present invention. [Figure 20] FIG. 13 is a configuration explanatory diagram of a seventh embodiment of an expansion joint according to the present invention. [Figure 21] FIG. 13 is a configuration explanatory diagram of an eighth embodiment of an expansion joint according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] (First embodiment of expansion joint) A first embodiment of an expansion joint according to the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the embodiment described below.

[0020] As shown in Fig. 2, a duct 1 is connected to the vibrating sieve 20 for supplying fluids or fluid matter such as exhaust gas discharged from a combustion device to the vibrating sieve 20, and a duct 3 is connected to the vibrating sieve 20 for discharging fluids treated by the vibrating sieve 20 from the vibrating sieve 20. In this embodiment, an expansion joint 10 is installed at the joint between the vibrating sieve 20 and the duct 1, and an expansion joint 11 is installed at the joint between the vibrating sieve 20 and the duct 3. The specific structures of the expansion joints 10 and 11 will be described below with reference to Fig. 1.

[0021] In FIG. 1, the fluid flows from top to bottom, the right side is the outside, and the left side is the inside of the piping members and expansion joints, that is, the fluid side.

[0022] As shown in FIG. 1, the expansion joints 10 and 11 of this embodiment include an inner tube 100 and a tubular piping member 101 that is arranged on the outside of the inner tube 100 and has a single-layer or multiple-layer structure, and the outermost layer of the piping member 101 is made of a material that has a hardness in the range of 30Hs to 55Hs, a tensile strength in the range of 5MPa to 20MPa, an elongation in the range of 400% to 1000%, and a tear strength in the range of 10kN / m to 100kN / m.

[0023] In addition, in Figure 1, for the sake of convenience, only the right side portions of the inner tube 100 and the piping member 101 with respect to the central axis C are shown, and the left side portions, which are symmetrical with respect to the central axis C, are omitted (the same applies to the embodiments shown in Figures 9 to 21 described later).

[0024] As shown in FIG. 1, the expansion joints 10, 11 of this embodiment further include, in addition to the inner tube 100 and the piping member 101, a pair of flanges 103, 104 that are installed at both ends of the piping member 101 in the central axial direction (direction along the central axis C) and are fixed to the vibrating sieve 20 and the ducts 1, 3, respectively.

[0025] As shown in Fig. 1, the expansion joints 10 and 11 of this embodiment include, as the pair of flanges, a first flange 103 and a second flange 104. The first flange 103 is installed on one end side (upper side in Fig. 1) in the axial direction (also referred to as the longitudinal direction) of the piping member 101, and the second flange 104 is installed on the other end side (lower side in Fig. 1) in the axial direction of the piping member 101.

[0026] Each of the first flange 103 and the second flange 104 includes a first holder 108 and a second holder 109, respectively, as a plurality of pairs of holders (support holders for shipping bolts 110, described below) that are distributed in the circumferential direction.

[0027] Furthermore, each of the first holder 108 and the second holder 109 has a through hole formed therethrough, and both axial ends of a shipping bolt 110 are inserted into the through hole, and the distance between the first flange 103 and the second flange 104, and therefore the length of the expansion joints 10, 11 in the central axial direction, can be adjusted by a bolt screwed into the shipping bolt 110.

[0028] The piping member 101 of this embodiment has a multi-layer structure in which an inner skin layer 115, an elastic layer 114, and an outermost seal layer 113 are laminated in this order from the inside. In other words, the piping member 101 includes a gasket 102, an outermost seal layer 113 made of vibration-resistant silicone rubber from the outside air side, an elastic layer 114 made of glass felt, an inner skin layer 115 made of glass cloth and flexible wire mesh, and a first inner cylinder portion 105 and a second inner cylinder portion 106 that protect the inner surface from dust.

[0029] In this embodiment, the outermost sealing layer 113 is made of a material having the above physical properties.

[0030] The outermost sealing layer 113 can be made of any material having a hardness of 30Hs to 55Hs, a tensile strength of 5MPa to 20MPa, an elongation of 400% to 1000%, and a tear strength of 10kN / m to 100kN / m, as measured in accordance with JIS K6253 using a type A durometer rubber hardness tester.

[0031] Specific examples include silicone rubber, fluororubber, chloroprene rubber, nitrile rubber, hydrogenated nitrile rubber, urethane rubber, ethylene rubber, butyl rubber, ethylene propylene rubber, silicone modified ethylene propylene rubber, acrylic rubber, natural rubber, epichlorohydrin rubber, chlorosulfonated polyethylene rubber, polytetrafluoroethylene (PTFE), and the like. In particular, highly elongated silicone rubber for vibration resistance is preferred.

[0032] More preferred ranges are a hardness of 30 to 45 Hs, a tensile strength of 10 to 20 MPa, an elongation of 600 to 800%, and a tear strength of 45 kN / m to 65 kNm.

[0033] By using such a material, even if displacement occurs due to vibration, the outermost seal layer 113 expands and contracts within the elastic range of the material in response to the vibration, making it less likely for wrinkles to form in the outermost seal layer 113, and thus suppressing damage to the expansion joints 10, 11 due to vibration.

[0034] If the elongation rate of the outermost seal layer 113 is less than 400%, the expansion joint 10 will have insufficient elasticity, and the full effect of the present invention will not be obtained. If the elongation rate of the outermost seal layer 113 is 1000% or more, the expansion joints 10, 11 will tend to have insufficient hardness. Furthermore, if the tear strength is less than 10 kN / m, if part of the outermost seal layer 113 of the expansion joint 10 is damaged during an installation work process or the like, the damaged area will tend to expand, and if the tear strength is more than 100 kN / m, flexibility will be adversely affected.

[0035] Furthermore, the thickness of the outermost sealing layer 113 can be appropriately selected within the range of 0.3 to 3 mm.

[0036] The gasket 102 can be made of a sheet material in which silicon rubber is applied to or impregnated in glass cloth, or a gasket material in which glass cloth is combined with various rubbers such as natural rubber and fluororubber, chloroprene rubber, nitrile rubber, hydrogenated nitrile rubber, urethane rubber, ethylene rubber, butyl rubber, ethylene propylene rubber, acrylic rubber, epichlorohydrin rubber, chlorosulfonated polyethylene rubber, etc. In particular, silicon glass cloth in which silicon rubber is applied to or impregnated in glass cloth, and a rubberized tape material in which natural rubber is processed on both sides of glass cloth can be preferably used.

[0037] The gasket 102 may have a thickness of 0.2 to 7 mm, and preferably has a thickness of 0.3 mm to 3 mm.

[0038] Also, it is preferable that the gasket 102 is disposed individually on both the first flange 103 and the second flange 104. Furthermore, it is preferable that the gasket 102 is extended along the outermost seal layer 113 from the portion sandwiched between the first flange 103 and the second flange 104, and is assembled such that the multiple corners of the flanges 103 and 104 do not come into direct contact with the outermost seal layer 113.

[0039] The gasket 102 is shaped to encase and cover the curved portions 115a, 115a at both ends of the inner layer 115 and the curved portions 113a, 113a at both ends of the outermost sealing layer 113, and has a raised portion that covers the outer periphery of the portions 113b, 113b of the outermost sealing layer 113 near the curved portions 113a, 113a.

[0040] Furthermore, an end of the gasket 102 extending along the outermost seal layer 113 may have a gap so that the end of the gasket 102 does not come into direct contact with the outermost seal layer 113. The gap between the end of the gasket 102 and the outermost seal layer 113 may be provided by bending the gasket 102 by hand or hand tools before or during installation of the expansion joint 10, or a gap may be formed between the gasket 102 and the outermost seal layer 113 by deforming the portion of the gasket 102 protruding from the flange on the outermost seal layer 113 side toward the outside by vibration of the vibrating sieve 20.

[0041] If a gap is provided between the end of the gasket 102 and the outermost sealing layer 113, when the spacing of the gap changes due to the vibration of the vibrating sieve 20 while the vibrating sieve 20 is in operation, air flows within the gap, causing any foreign matter that has entered the gap to be expelled, thereby reducing deterioration of the outermost sealing layer 113 due to the foreign matter.

[0042] Furthermore, since the gasket 102 is raised in a substantially vertical direction and is longer than the thickness of the first flange 104 so as to fit along the outermost seal layer 113, even when performing maintenance such as applying anti-rust paint to the flange 104, paint or the like can be prevented from flowing into the outermost seal layer 113, and deterioration of the outermost seal layer 113 due to solvents or resins can be prevented.

[0043] Furthermore, in order to prevent the gasket 102 from striking the outermost seal layer 113 due to the vibration of the vibrating sieve 20, the excess portion of the gasket 102 folded back can be fixed to the first flange 103, the second flange 104, etc.

[0044] The gasket 102 prevents the outermost seal layer 113 from being damaged by direct rubbing against the corners of the first flange 103 and the second flange 104. Furthermore, the gasket 102 prevents the outermost seal layer 113 from being damaged by a ratchet tool, an air tool, an impact socket wrench, an adjustable wrench, or the like when the expansion joints 10, 11 are attached to the vibrating sieve 20 and the duct.

[0045] Moreover, the gasket 102 is fastened by the first flange 103 and the second flange 104 in a state of contact with the outermost seal layer 113 (see FIG. 1). This makes it possible to prevent the outermost seal layer 113 from being damaged due to direct contact with unevenness (convexoconcave), scratches, and metal processing marks on the surfaces of the first flange 103 and the second flange 104. This also makes it possible to prevent the outermost seal layer 113 from being pulled out from the surfaces of the first flange 103 and the second flange 104 due to friction between the outermost seal layer 113 and the gasket 102 and being damaged when the outermost seal layer 113 expands and contracts due to the vibrating sieve 20.

[0046] The gasket 102 and the outermost sealing layer 113 may be fixed to the first flange 103 and the second flange 104 using a combination of an adhesive and a pressure sensitive adhesive.

[0047] The elastic layer 114 is made of inorganic or organic felt or bulk material, and preferred are felts and bulk materials made of ceramic fibers, rock wool fibers, glass fibers, metal fibers, carbon fibers, silicon carbide fibers, aramid fibers, polyacrylate fibers, polyamide fibers, polyamideimide fibers, melamine fibers, phenolic fibers, polyester fibers, cellulose fibers, etc.

[0048] The inner skin layer 115 is made of one or more materials selected from wire mesh, metal fiber cloth, inorganic fiber cloth, and organic sheet materials, among which inorganic fiber cloth such as ceramic cloth and glass cloth is preferable. In particular, glass cloth is available in various thicknesses and varieties, and in addition to general-purpose glass cloth, heat-resistant glass cloth, glass cloth with SUS wire, glass cloth with aluminum foil, and glass cloth with SUS foil are preferable. As the organic sheet material, a heat-resistant sheet material such as a polytetrafluoroethylene (PTFE) sheet can be appropriately selected.

[0049] The role of the elastic layer 114 is to provide heat insulation and dust protection for the outermost seal layer 113, and it is preferable to use an elastic layer that does not inhibit the flexibility of the outermost seal layer 113. The thickness of the elastic layer 114 is set to a thickness that reduces the temperature to the heat resistance temperature of the outermost seal layer 113 against heat received from the fluid flowing on the inner surface side of the expansion joints 10, 11.

[0050] The thickness of the inorganic fiber cloth of the inner skin layer 115 can be appropriately selected within the range of 0.2 mm to 5 mm. If it is less than 0.2 mm, the strength is insufficient and sufficient reinforcing effect cannot be obtained, and if it is thicker than 5 mm, the flexibility is insufficient, which adversely affects the processability and stretchability of the bellows.

[0051] Furthermore, as shown in FIG. 1, it is preferable that the elastic layer 114 and the inner skin layer 115 are formed so as to have a convex portion on the fluid side in the center of the piping member 101 .

[0052] Next, the structure of the inner cylinder 100 will be specifically described.

[0053] 1, the inner cylinder 100 of this embodiment is fixed to a pair of flanges 103, 104, respectively, and is composed of a first inner cylinder portion 105 and a second inner cylinder portion 106 that are relatively displaceable, and the first inner cylinder portion 105 and the second inner cylinder portion 106 are arranged so as to partially face each other in a direction perpendicular to the central axis direction of the expansion joints 10, 11. In other words, the first inner cylinder portion 105 and the second inner cylinder portion 106 have portions that overlap (overlap portions) for a predetermined length in the axial direction.

[0054] In addition, the first inner tube portion 105 has a shape such that the diameter gradually decreases from one end to halfway in the direction of the central axis of the piping member 101, and then the diameter remains constant from halfway to the other end, and the second inner tube portion 106 has a shape such that the diameter is constant along the central axis of the piping member 101.

[0055] One end of the first flange 103 and the second flange 104 extends inside the expansion joint 10, and a first inner cylindrical portion 105 and a second inner cylindrical portion 106 are provided across the extending portions of these flanges 103, 104.

[0056] The materials and structures of the members of the first inner cylinder portion 105 and the second inner cylinder portion 106 can be selected appropriately depending on the properties of the fluid inside the expansion joint 10. In this embodiment, they are made of stainless steel, which has a high hardness and is intended to prevent the fluid from damaging the fluid-exposed surfaces of the expansion joints 10 and 11 and to prevent deterioration due to rust.

[0057] As shown in Fig. 1, the first inner cylinder portion 105 is a substantially broken line having two obtuse angles. The first inner cylinder portion 105 is configured so that the angles formed by both ends of the first inner cylinder portion 105 are substantially right angles. Furthermore, the first inner cylinder portion 105 has a tapered portion 105a that is tapered in diameter from one end in the axial direction (upper end in Fig. 1) to the other end in the axial direction (lower end in Fig. 1), and a constant diameter portion 105b that extends with a constant diameter from the end of the tapered portion 105a to the other end in the axial direction.

[0058] On the other hand, the second inner cylinder portion 106 has a shape having a side that is substantially inverted T-shaped and a side that is abutted from the left end to the center of the inner cylinder so that the angle formed is substantially 45°. The second inner cylinder portion 106 has a substantially cylindrical shape that extends with a constant diameter, has a larger diameter than the constant diameter portion 105b of the first inner cylinder portion 105, and is disposed outside the constant diameter portion 105b.

[0059] Furthermore, the first inner cylinder portion 105 and the second inner cylinder portion 106 are disposed so that the lower portion of the first inner cylinder portion 105 and the upper portion of the second inner cylinder portion 106 face each other (overlap in the direction) at a predetermined distance in a direction perpendicular to the fluid flow direction (or the central axis direction of the expansion joints 10, 11) so that they can be displaced in the fluid direction. That is, the constant diameter portion 105b of the first inner cylinder portion 105 and the second inner cylinder portion 106 overlap (lap) for a predetermined length in the axial direction.

[0060] The first flange 103 and the second flange 104 are provided with connecting bolt holes for connecting the expansion joints 10, 11 to a mating pipe (not shown), and the number of connecting holes is the same as the number of communicating bolt holes of the corresponding mating pipe flanges. The expansion joint 10 and the mating pipe are connected by inserting bolts through the connecting holes and screwing nuts onto the bolts.

[0061] With this configuration, the outermost sealing layer 113 of the expansion joints 10, 11 is protected from dust in the first inner cylinder portion 105 and the second inner cylinder portion 106, and the inflow of dust is prevented by the elastic layer 114 made of glass felt and the inner skin layer 115 made of glass cloth and flexible wire mesh.

[0062] The holder 108 and the holder 109 are disposed so as to face each other in a substantially vertical direction, and extend in an outer direction (radially outward) of the piping member 101. Furthermore, an insertion hole for inserting both axial ends of the shipping bolt 110 therethrough is provided at one end of the holder 108 and the holder 109 in the extending direction.

[0063] The shipping bolt 110 is installed by inserting both axial ends thereof into the insertion holes of the holders 108, 109, and is connected by screwing a plurality of nuts 111 to fix the shipping bolt 110 to the holders 108, 109. As a result, the pair of holders 108, 109 are positioned and fixed at predetermined axial positions of the shipping bolt 110, and the distance between the holders 108, 109 is maintained.

[0064] As a result, the distance between the pair of flanges 103, 104 is maintained via the holders 108, 109, so that both axial ends of the piping member 101 held and fixed to both flanges 103, 104 are stretched to a predetermined length, and the expansion joints 10, 11 are installed at the joints between the vibrating sieve 20 and the ducts 1, 3 in a state in which a predetermined tension is applied. Note that before the vibrating sieve 20 is started, the shipping bolts 110 are removed from the holders 108 and 109. As a result, the piping member 101 that has been stretched and given a predetermined tension is maintained (held) at the predetermined length.

[0065] The expansion joints 10 and 11 described above have a generally tubular shape, but are not limited to this shape. For example, the expansion joints may be cylindrical or rectangular in shape depending on the shape of the duct piping of the property to which they are applied.

[0066] (How to install expansion joints) Next, a method for installing the expansion joint according to the present invention will be specifically described together with the detailed structure of the vibrating sieve 20.

[0067] That is, this method of installing an expansion joint includes the steps of fixing the expansion joints 10, 11, which are manufactured to have a first designated length in the central axis direction, to the vibrating sieve 20 and the ducts 1, 3, respectively; applying a force (tension) to the expansion joints 10, 11 so that the expansion joints 10, 11 are maintained in a state stretched to a second designated length that is longer than the first designated length; and releasing the tension from the expansion joints 10, 11, and includes a state in which, after the step of releasing the tension, the state of the expansion joints 10, 11 changes from the second designated length to a third designated length that is at least longer than the first designated length.

[0068] Furthermore, the method of installing the expansion joint in the case where the flanges 103, 104 are included includes the steps of fixing the expansion joint 10, 11, which is manufactured to have a first designated length in the central axis direction, to the vibrating sieve 20 and the ducts 1, 3, respectively, by each of the pair of flanges 103, 104, applying tension between the pair of flanges 103, 104 so that the expansion joints 10, 11 are maintained in a stretched state to a second designated length that is longer than the first designated length, and releasing the tension from the pair of flanges 103, 104, and includes a state in which the state of the expansion joints 10, 11 changes from the second designated length to a third designated length that is at least longer than the first designated length after the step of releasing the tension.

[0069] In the installation method of this embodiment, the first specified length may be set to 50% to 100% of the length calculated by subtracting the vibration amplitude of the vibrating sieve 20 from the second specified length.

[0070] As shown in FIG. 2, the vibrating sieve 20 of this embodiment comprises a trough 201 that is generally gutter-shaped with an open upper portion and extends a predetermined length to serve as a passage for fluid, a cover 202 that covers the upper opening of the trough 201, a motor 206 that imparts vibration to the trough 201 via a transmission belt or the like, a vibrating sieve inlet side flange 214 (hereinafter also referred to simply as "flange 214") having a first opening that communicates with an inlet located upstream of the trough 201, a vibrating sieve outlet side flange 211 (hereinafter also referred to simply as "flange 211") having a second opening that communicates with an opening located midway in the extension direction of the trough 201, and a trough downstream side flange (hereinafter also referred to simply as "flange 212") having a third opening that communicates with a outlet located downstream of the trough 201.

[0071] 2, a vibrating screen inlet side flange 210 (hereinafter, simply referred to as "flange 210") is disposed facing the flange 214 at a predetermined distance (in this embodiment, the flange 210 is disposed facing the flange 214 above). An expansion joint 10 is installed between the flange 210 and the flange 214.

[0072] 2, a vibrating sieve outlet side flange 213 (hereinafter, simply referred to as "flange 213") is disposed facing the flange 211 at a predetermined distance (in this embodiment, the flange 213 is disposed facing below the flange 211). An expansion joint 11 is installed between the flange 211 and the flange 213.

[0073] Although not specifically shown, in this embodiment, a vibrating sieve outlet side flange is disposed opposite the flange 212 at a predetermined distance, and an expansion joint may be further installed between this vibrating sieve outlet side flange and flange 212.

[0074] During installation, flanges 210 and 214, and flanges 211 and 213 are configured to maintain a vertical distance of 100 to 500 mm between them, and expansion joints 10, 11 are respectively installed between the flanges as described above.

[0075] The length of the expansion joints 10, 11 corresponding to this interval is defined as the "second specified length" (the length stretched by applying tension). The second specified length is indicated as L2 in Fig. 1. In this embodiment, the length of the expansion joints 10, 11 corresponding to the interval between the flanges 210, 214 and the flanges 211, 213 means the longest axial length of the piping members 101 constituting each expansion joint 10, 11 (here, the length between the outer surfaces at the upper and lower ends of the inner skin layer 115).

[0076] At this time, the distance between the first flange 103 and the second flange 104, and therefore the length of the expansion joints 10, 11 in the central axis direction, can be adjusted via the first holder 108, 109 by the shipping bolt 110 and the nut 111 passing through the through holes formed in the first holder 108 and the second holder 109 (see FIG. 1). That is, the shipping bolt 110 and the nut 111 apply a force (tension) between the first flange 103 and the second flange 104 so that the expansion joints 10, 11 are maintained in a state stretched to the second designated length L2 that is longer than the first designated length L1 (see FIG. 3A).

[0077] Furthermore, when motor 206 is started, vibration occurs in the vertical direction, causing a change in the vertical distance between flange 210 and flange 214. The length of expansion joint 10 according to the minimum vertical distance between flange 210 and flange 214, taking into account the vibration amplitude, when motor 206 is operating is defined as the "third specified length."

[0078] In this embodiment, since a displacement of 5 mm to 40 mm in the substantially vertical direction was confirmed, the third specified length is set to 60 to 460 mm. The third specified length can be changed arbitrarily. It is also self-evident that the vibration amplitude at the start of the motor changes depending on the position and type of the vibrating sieve and motor used.

[0079] Then, from the state in which the expansion joints 10, 11 are maintained at the second designated length L2 by the pair of flanges 103, 104 via holders 108, 109 which are positioned and fixed by shipping bolts 110 and nuts 111 (see Figure 1), by removing the shipping bolts 110 and nuts 111 from the holders 108, 109, the force acting between the first flange 103 and the second flange 104 is released, and the expansion joints 10, 11 can change from the second designated length L2 to the third designated length.

[0080] Additionally, the outermost seal layer 113 of the expansion joint 10 and the expansion joint 11 is fabricated so that its length is 50% to 100% of the calculated length (first designated length). The first designated length is indicated as L1 in FIG. 3A. Since the calculated length is longer than the first designated length L1, the expansion joint 10 and the expansion joint 11 are extended to a length (second designated length) longer than the calculated length when installed. The second designated length is also indicated as L2 in FIG. 3B.

[0081] The calculated length is set to be longer than the first designated length L1 and shorter than the second designated length L2. The third designated length is set to be longer than the first designated length. That is, in this installation method, the second designated length L2>the third designated length>the first designated length L1.

[0082] With the above-mentioned configuration, the expansion joints 10 and 11 are stretched within the elastic range of the outermost seal layer 113 during installation, which prevents wrinkles from occurring in the expansion joints 10 and 11. Furthermore, since there is still some room in the elastic range during installation, even if a displacement occurs due to vibrations that are larger than those in a steady operating state when the vibrating sieve 20 is started or stopped, the expansion joints 10 and 11 are prevented from wrinkles or from being damaged due to overstretching.

[0083] An object (fluid, liquid material, etc.) to be subjected to the vibrating sieve 20 flows from the duct 1 into the inner cylinder 100 through an opening on the inside of the flange 210, passes through the inner cylinder 100, and is then fed into the receiving plate 203 through a first opening of the flange 214. The bottom of the trough 201 and the motor 206 are connected via a transmission belt or the like, and when the motor 206 is driven, the object subjected to the vibrating sieve 20 moves from the receiving plate 203 toward the right end of the trough 201.

[0084] In addition, a liner 204 and a louver screen 205 are provided at the bottom of the trough 201, and the object to be subjected to the vibrating sieve 20 is oscillated to a flange 211 or a flange 212 having a third opening depending on the particle size of the object.

[0085] Furthermore, the upper part of flange 211 is connected to the lower part of trough 201, and below louver screen 205, trough 201 has an inclined surface 201a that gradually narrows downward. Since flange 211 is located at the bottom of inclined surface 201a, an object that passes through louver screen 205 proceeds to flange 211.

[0086] Furthermore, since the upper part of the third opening is connected to the lower part of the trough 201 and the third opening extends in an approximately vertical direction, objects that do not pass through the louver screen 205 proceed to the third opening.

[0087] In addition, an anti-vibration spring 207a is connected to the receiving plate 203, and an anti-vibration spring 207b is connected to the trough 201 in which the louver screen 205 is installed. The anti-vibration springs 207a and 207b are connected to the stationary stands 208a and 208b, respectively, and suppress the transmission of vibrations caused by the vibrating sieve 20 to the floor surface.

[0088] (Action and effect) Next, the effects of the expansion joints 10, 11 having the above-mentioned configuration and the installation method thereof will be described.

[0089] That is, in the expansion joints 10 and 11, the outermost layer of the piping member 101 (here, the outermost seal layer 113) is formed of a material having a hardness in the range of 30Hs to 55Hs, a tensile strength in the range of 5MPa to 20MPa, an elongation in the range of 400% to 1000%, and a tear strength in the range of 10kN / m to 100kN / m, so that wrinkles are less likely to occur in the outermost layer of the piping member 101. As a result, even if the expansion joints 10 and 11 installed at the joints between the vibrating sieve 20 and the ducts 1 and 3 are subjected to vibrations from the vibrating sieve for a long period of time, the durability of the expansion joints can be improved.

[0090] In addition, in this embodiment, the inner tube 100 is fixed to each of a pair of flanges 103, 1040, and is composed of a first inner tube portion 105 and a second inner tube portion 106 that are relatively displaceable, and the first inner tube portion 105 and the second inner tube portion 106 are arranged so as to partially face each other in a direction perpendicular to the central axis direction of the expansion joints 10, 11.

[0091] According to the above embodiment, since the inner cylinder 100 has the above-mentioned configuration, the axial length of the inner cylinder 100 can be changed, and the expansion joints 10, 11 can be flexibly adapted to the expansion and contraction of the expansion joints 10, 11. Therefore, when the expansion joints 10, 11 are stretched and tension is applied to the outermost layer (the outermost seal layer 113) of the piping member 101, the expansion joints 10, 11 are installed at the joints between the vibrating sieve 20 and the ducts 1, 3, and the expansion joints 10, 11 can be easily maintained in a state in which tension is applied.

[0092] Furthermore, in this embodiment, as shown in FIG. 1, the first inner tube portion 105 has a shape such that the diameter gradually decreases from one end to a middle portion in the direction of the central axis of the piping member 101, and then the diameter remains constant from the middle portion to the other end, and the second inner tube portion 106 has a shape such that the diameter is constant along the central axis of the piping member 101.

[0093] According to the above embodiment, since the first inner cylinder portion 105 has the above-mentioned shape, it is possible to easily circulate fluids, fluid substances, and the like from one end to the other end within the first inner cylinder portion 105. Furthermore, since the second inner cylinder portion 106 has the above-mentioned shape in addition to the above-mentioned shape of the first inner cylinder portion 105, it is easy to ensure a certain gap between the opposing portions (portions overlapping in the axial direction) of the first inner cylinder portion 105 and the second inner cylinder portion 106. As a result, it is possible to suppress interference between the first inner cylinder portion 105 and the second inner cylinder portion 106, making it easy to stretch the expansion joint.

[0094] In addition, the method of installing the expansion joint includes the three steps described above, and also includes a state in which, after the step of releasing the force, the state of the expansion joints 10, 11 changes from the second designated length L2 to a third designated length that is at least longer than the first designated length L1.

[0095] Therefore, when the expansion joints 10, 11 are installed and set up at the joints between the vibrating sieve 20 and the ducts 1, 3, the expansion joints 10, 11 stretched to the second designated length L3 are maintained at the third designated length which is longer than at least the first designated length L1 (the initial length at the time of manufacture), thereby preventing wrinkles from occurring in the expansion joints 10, 11.

[0096] (Second embodiment of expansion joint) 9 to 12 show a second embodiment of the expansion joint according to the present invention. Note that parts that are substantially the same as those in the above embodiment are given the same reference numerals and their explanation will be omitted.

[0097] 9 has a pair of fixing members 50, 51 for fixing both ends in the central axial direction of a piping member 101 to the vibrating sieve and the duct, respectively. Each of the fixing members 50, 51 has a fixing portion 53 for fixing an end of the piping member 101, and a protruding portion 55 that protrudes radially outward from the fixing portion 53 while being bent or curved in a direction approaching the mating fixing member.

[0098] The piping member 101 in the second embodiment is a single layer, and both axial ends thereof are bent outward to form bent portions 101a and 101b. Furthermore, the inner cylinder 100 is gradually tapered in diameter from one axial end to the other axial end.

[0099] The fixing member 50 is for fixing one axial end (bent portion 101a) of the piping member 101 to either the duct or the vibrating sieve, and is disposed on the upstream side of the fluid flowing through the inner cylinder 100. The fixing member 51 is disposed opposite to the fixing member 50, for fixing the other axial end (bent portion 101b) of the piping member 101 to the other of the duct or the vibrating sieve, and is disposed on the downstream side of the fluid flowing through the inner cylinder 100.

[0100] The fixing members 50, 51 have a fixing portion 53 extending a predetermined length perpendicular to the central axis C of the inner tube 100, a bent portion 57 which protrudes slightly radially outward from the extending tip of the fixing portion 53 and extends a predetermined length while bending perpendicularly toward the opposing fixing member (toward the fixing member 51 in the case of the fixing member 50, and toward the fixing member 50 in the case of the fixing member 51), and a protruding portion 59 which protrudes a predetermined length from the extending tip of the bent portion 57 radially outward from the piping member 101 so as to be perpendicular to the central axis C of the inner tube 100, and the entire fixing members 50, 51 are approximately crank-shaped.

[0101] A bolt insertion hole (not shown) through which a bolt 61 is inserted is formed at the base end of the fixing portion 53 in the extension direction, and a bolt insertion hole (not shown) through which a shipping bolt 110 is inserted is formed at the tip end of the protruding portion 59 in the extension direction. Furthermore, the pair of fixing members 50, 51 are arranged so that the distance between the protruding portions 59, 59 is narrower than the distance between the fixing portions 53, 53 (see FIG. 9).

[0102] Further, the base ends in the extending direction of the fixing portions 53, 53 of the fixing members 50, 51 are fixed to the annular joint side flanges 112, 112 by welding or the like.

[0103] The bent portion 57 and the protruding portion 59 form the "protruding portion" of the present invention.

[0104] The flanges 210, 214 are fixed to the outer surfaces of the ends of the cylindrical ducts 210a, 214a by welding or the like, and protrude in the horizontal direction.

[0105] Furthermore, an end portion of the piping member 101 is covered with gaskets 102, 102. That is, the outer periphery of the bent portions 101a, 101b of the piping member 101 is covered so as to be wrapped with the gaskets 102, 102, and the outer periphery of the portions 101c, 101d of the piping member 101 near the bent portions 101a, 101b are also covered with the gaskets 102, 102.

[0106] A bent portion 101 a at one axial end of the piping member 101 is sandwiched between the flange 210 and the joint-side flange 112 while being covered with a gasket 102 , and then is fastened and fixed with a bolt 61 and a nut 62 .

[0107] Similarly, the bent portion 101b at the other axial end of the piping member 101 is covered with a gasket 102 and is sandwiched between the flange 214 and the joint side flange 112, and then is fastened and fixed with a bolt 61 and a nut 62.

[0108] The bolt 61 may be separate from the joint-side flange 112, or may be a stud bolt preliminarily welded to the joint-side flange 112. In this case, from the viewpoint of improving the workability of tightening the bolt and nut, it is preferable that the shaft portion of the stud bolt is erected so as to face the flanges 210, 214 (the shaft portion of the stud bolt is disposed facing outward in the axial direction of the joint).

[0109] Furthermore, by inserting both axial ends of the shipping bolt 110 into bolt insertion holes (not shown) of the protruding portions 59, 59 and tightening and fixing them with a plurality of nuts 111, the piping member 101 is stretched to a predetermined second designated length L2 and is positioned in a tensioned state.

[0110] In the expansion joint 10A of this embodiment, the pair of fixing members 50, 51 have the protruding parts 55, 55 having the above-mentioned configuration, so even if the piping member 101 deforms radially outward, the deformation can be tolerated. In other words, even if the piping member 101 deforms radially outward, the deformed part enters the space between the fixing part and the protruding part 55, more specifically, the space R provided between the fixing part 53 and the bent part 57.

[0111] As a result, the piping member 101 is less likely to interfere with the fixing members 50 and 51, and thus it is possible to prevent wrinkles or damage to the outermost layer of the piping member 101 (the outer surface layer of the piping member 101 since the piping member 101 is a single layer in this case). It is preferable to form the shape of the part of the fixing members 50 and 51 that may interfere with the piping member 101 into a gentle curved shape, such as the curved part 58 shown by the two-dot chain line in Fig. 9 (this will be described in paragraph 0141), because this can prevent wrinkles or damage even if the piping member 101 is significantly deformed due to blockage of the piping path or abnormal pressure.

[0112] In addition, the shipping bolt 110 is configured to be tightened and fixed with multiple nuts 111 by utilizing the protruding portions 59, 59 of the protruding portions 55, 55 that constitute the pair of fixing members 50, 51, which are spaced narrower than the fixing portions 53, 53, so that the axial length of the shipping bolt 110 can be shortened.

[0113] The gasket 102 seals gaps between the bent portions 101a, 101b of the piping member 101 and the flanges 210, 214. In addition, since the gasket 102 is configured to cover the adjacent portions 101c, 101d of the piping member 101, the gasket 102 also seals the gap between the piping member 101 and the flange joint side flange 112. Therefore, the sealing property (sealing performance) of the piping member 101 can be improved.

[0114] FIG. 10 shows a first modified example of the expansion joint of the second embodiment.

[0115] The expansion joint 10B of this first modified example differs from that of Fig. 9 in the structure of the inner tube 100. That is, the inner tube 100 of this first modified example is provided with a bent portion 100a that is bent outward at one end in the axial direction.

[0116] Then, the bent portion 101a of the piping member 101 covered with the gasket 102, the bent portion 100a of the inner tube 100 placed on the bent portion 101a, and a gasket 102a placed on the bent portion 100a and separate from the gasket 102 are clamped between the flange 210 and the joint side flange 112, and are fastened by the bolts 61 and nuts 62.

[0117] Incidentally, with the expansion joint 10B of this first modified example as well, it is possible to obtain the same operational effects as those of the expansion joint 10A shown in FIG. 9 (see paragraphs 0111 to 0113).

[0118] In addition, a bent portion 100a is provided at one axial end of the inner tube 100, and the inner tube 100 is fixed to a flange 210 or the like using this bent portion 100a. As a result, the piping member 101 and the inner tube 100 can be separated, and the piping member 101 is less susceptible to the effects of heat from the fluid flowing through the inner tube 100, for example.

[0119] FIG. 11 shows a second modified example of the expansion joint of the second embodiment.

[0120] The expansion joint 10C of this first modified example differs from that of Fig. 10 in the structure of the inner cylinder 100. That is, the inner cylinder 100 of this second modified example has a first inner cylinder portion 105 having a structure similar to that of the inner cylinder 100 of Fig. 10, and also has a double cylinder structure having a second inner cylinder portion 106.

[0121] The first inner cylinder portion 105 has a bent portion 105c bent outward at one axial end portion thereof. The second inner cylinder portion 106 has a fixed portion 106a that is clamped and fixed between the bent portion 101b at the other axial end portion of the piping member 101 and the flange 214, and a standing portion 106b that stands vertically from the radially inner side of the fixed portion 106a, and the standing portion 106b overlaps the tip end of the first inner cylinder portion 105 in the extending direction by a predetermined length.

[0122] In addition, a protective member 140 is attached to the tip of the standing portion 106b. In this embodiment, the protective member 140 is an annular member having a circular cross section, and is fixed to the tip of the standing portion 106b by welding, adhesion, etc. Note that the protective member 140 may have an elliptical cross section, for example, as long as the outer surface is curved.

[0123] By providing protective member 140 having a curved outer surface as described above at the terminal portion of a specified member, the terminal portion of the specified member is prevented from coming into direct contact with other members placed near the terminal portion of the specified member (terminal portions having corners, edges, burrs, etc. do not come into contact with other members), and since protective member 140 having a curved outer surface comes into contact with the other members, damage to the other members can be suppressed (breakage due to contact with corners, etc. is mitigated).

[0124] In this embodiment, even if the piping member 101 is deformed radially inward, the tip of the standing portion 106b does not directly contact the piping member 101, but the protective member 140 contacts the piping member 101, thereby suppressing damage to the piping member 101.

[0125] The same effects can be obtained in the embodiments shown in Figs. 1, 12, 16 to 18, and 20.

[0126] 1, damage to the inner skin layer 115 can be suppressed, and in the embodiments of FIGS. 12 and 16, damage to the dustproof member 107 can be suppressed. In the embodiment of FIGS. 17 and 18, a protective member 140 is fixed to the tip of the duct 5, which can suppress damage to the gasket 102 and the inner tube 100. Furthermore, in the embodiment of FIG. 20, protective members 140 are fixed to the tip of the ducts 6 and 7, respectively, which can suppress damage to the gasket 102 and the piping member 101.

[0127] Then, the bent portion 101a of the piping member 101 covered with the gasket 102, the bent portion 105c of the first inner cylinder portion 105 placed on the bent portion 101a, and the gasket 102a placed on the bent portion 105c are clamped between the flange 210 and the joint side flange 112, and then tightened and fixed with the bolts 61 and nuts 62.

[0128] In addition, the fixed portion 106a of the second inner tube portion 106, the bent portion 101b of the piping member 101 placed on the fixed portion 106a and covered with the gasket 102, and the gasket 102a arranged on the underside of the fixed portion 106a are clamped between the flange 214 and the joint side flange 112, and are tightened and fixed with the bolts 61 and nuts 62.

[0129] As a result, the piping member 101 is stretched to the predetermined second designated length L2 and is disposed in a state in which tension is applied.

[0130] In the expansion joint 10C of the second modified example, it is possible to obtain the same effects as the expansion joint 10A shown in FIG. 9 and the expansion joint 10B shown in FIG. 10 (see paragraphs 0111-0113 and 0118).

[0131] Furthermore, by providing the upright portion 106b in the second inner tube portion 106, even if foreign matter such as sand, debris, or dust attempts to enter the gap K between the inner tube 100 and the piping member 101 from the gap (downward opening) between the first inner tube portion 105 and the second inner tube portion 106, the intrusion into the gap K can be suppressed, making it less likely that cracks or fissures will occur in the piping member 101.

[0132] FIG. 12 shows a third modified example of the expansion joint of the second embodiment.

[0133] The expansion joint 10D of this third modified example is basically similar to the structure in Figure 11, but has a structure in which a dustproof member 107 is inserted between the first inner cylinder portion 105 and the second inner cylinder portion 106, and the gap (downward opening) between the first inner cylinder portion 105 and the upright portion 106b of the second inner cylinder portion 106 is blocked.

[0134] This dustproof member 107 is composed of a cover, a filling member filled inside the cover, and a reinforcing member disposed on the outer periphery of the cover.

[0135] The cover may be the same as the elastic layer 114 described in paragraph 0047, and is preferably made of, for example, glass cloth or ceramic cloth.

[0136] As the filling member, the same material as the inner skin layer 115 described in paragraph 0048 can be used, and for example, glass felt, ceramic felt, or the like is preferable.

[0137] Furthermore, as the reinforcing member, for example, a wire mesh made of stainless steel or a nickel-based alloy can be used, and a knitted wire mesh having elasticity and flexibility can be preferably used.

[0138] The thicknesses of the above-mentioned cover, filling member and metal mesh member can be appropriately set, and the cover and reinforcing member may have a multi-layer structure.

[0139] The dustproof member does not necessarily have to include a reinforcing member, but if the dustproof member includes a reinforcing member, it is possible to protect and maintain the cover and the filling member.

[0140] Furthermore, in this third modified expansion joint 10D, it is possible to obtain the same effects as the expansion joint 10A shown in FIG. 9 and the expansion joint 10B shown in FIG. 10 (see paragraphs 0111-0113, 0118), and the dustproof member 107 arranged between the first inner tube portion 105 and the second inner tube portion 106 can prevent foreign matter from entering between the inner tube 100 and the piping member 101.

[0141] Further, the expansion joints 10A, 10B, 10C, and 10D of the second embodiment shown in FIGS. 9 to 12 have a shape that expands radially outward from the fixed portion 53 while bending in a direction approaching the opposing fixed member. However, for example, as shown in FIG. 9, the expansion joints may have a shape that expands radially outward from the tip of the extending direction of the fixed portion 53 while forming a curved shape toward the opposing fixed member (see curved portion 58 shown by the two-dot chain line in FIG. 9).

[0142] (Third embodiment of expansion joint) A third embodiment of the expansion joint according to the present invention is shown in Figures 13 to 16. Note that parts that are substantially the same as those in the above embodiment are given the same reference numerals and their explanation will be omitted.

[0143] 13 has a fixing frame 70 for fixing the other end in the central axial direction of a piping member 101 to a duct or the like, and the fixing frame 70 has a communication hole 74 formed therein that communicates with the gap K between the inner tube 100 and the piping member 101. Note that this communication hole 74 is capable of discharging foreign matter that has entered the gap K between the inner tube 100 and the piping member 101.

[0144] More specifically, the fixed frame 70 has a base 71 extending a predetermined length perpendicular to the central axis C of the piping member 101, and a fixed part 73 hanging down from one end of the base 71 in the extending direction (the end away from the inner cylinder 100), and forms a substantially L-shaped angle. The fixed frame 70 is disposed on the other axial end side of the piping member 101.

[0145] Moreover, one axial end of the first inner cylinder portion 105 is fixed to the inner surface of the lower end portion of the cylindrical body 80a by welding or the like.

[0146] Furthermore, a plurality of communication holes 74 are formed in the base 71. The other end of the base 71 of the fixed frame 70 in the extending direction is fixed to the outer surface of the second inner cylinder portion 106 by welding or the like.

[0147] The communication hole 74 is preferably provided in a location where foreign matter is likely to accumulate. Also, it is preferable to appropriately set the inner diameter, position, shape, etc. of the communication hole 74 so that the gap K between the inner tube 100 and the piping member 101 can be easily inspected for foreign matter accumulation and the state of the piping member 101 with an endoscope, visual inspection, a microscope, etc. Furthermore, it is more preferable to set the inner diameter, position, shape, etc. of the communication hole 74 so that the state of the fixed frames 70, 80 and the inner tube 100 can be inspected from the communication hole 74.

[0148] Furthermore, if two or more communication holes 74 are provided, each communication hole 74 can be used for lighting or inspection. For example, it is possible to perform suction cleaning or air blowing of the gap K through a specific communication hole 74, while checking the condition of the gap K and the piping member 101 or collecting dust through the other communication holes 74.

[0149] On the other hand, a fixed frame 80 having a similar shape to the fixed frame 70 is disposed opposite to one axial end of the piping member 101 .

[0150] That is, this fixing frame 80 also has a base 81 extending a predetermined length perpendicular to the central axis C of the piping member 101, and a fixing part 83 suspended from one end in the extending direction of the base 81, forming a substantially L-shaped angle. The other end in the extending direction of the base 81 of the fixing frame 80 is fixed to the outer surface of the lower end of the cylindrical body 80a by welding or the like.

[0151] Furthermore, the fixing portions 73, 83 of the respective fixing frames 70, 80 are formed with bolt insertion holes (not shown).

[0152] In this embodiment as well, the terminal portion of the piping member 101 is covered with the gaskets 102, 102. That is, the outer periphery of both axial end portions of the piping member 101 is covered so as to be wrapped with the gaskets 102, 102.

[0153] The other axial end of the piping member 101, covered with the gasket 102, is clamped between the fixing portion 73 of the fixing frame 70 arranged in contact with its inner surface and the pressing plate 112a arranged on the outer surface, and is then tightened and fixed with a bolt 61 and a nut 62.

[0154] Similarly, one axial end of the piping member 101, covered with the gasket 102, is clamped between the fixing portion 83 of the fixing frame 80 arranged in abutment against its inner side and the pressing plate 112a arranged on the outer side, and is tightened and fixed with a bolt 61 and a nut 62.

[0155] As a result, the piping member 101 is stretched to the predetermined second designated length L2 and is disposed in a state in which tension is applied.

[0156] In the expansion joint 10E of this embodiment, a communication hole 74 that communicates with the gap K between the inner tube 100 and the piping member 101 is formed in the fixed frame 70. Therefore, even if foreign matter such as sand, dirt, or dust gets into the gap K between the inner tube 100 and the piping member 101, the foreign matter can be smoothly discharged through the communication hole 74, making it less likely that cracks or fissures will occur in the piping member 101.

[0157] Also, for example, an air blow tube or a suction tube can be inserted through the communication hole 74 to clean or suck up foreign matter accumulated in the gap K, or to clean the piping member 101. Furthermore, by inserting a microscope or the like through the communication hole 74, the state of the gap K and the piping member 101 can be checked.

[0158] Furthermore, for example, a part of the base constituting the fixed frame may be formed into a mortar-like recess, i.e., a conical recess that expands in diameter at the top and gradually decreases in diameter toward the bottom, and a discharge hole may be formed at the bottom of the recess. In this case, foreign objects placed on the base of the fixed frame can be easily collected in the discharge hole and discharged smoothly.

[0159] FIG. 14 shows a first modified example of the expansion joint of the third embodiment.

[0160] The expansion joint 10F of this first modified example differs from that shown in FIG. 13 in the shape and structure of the fixed frames 70, 80.

[0161] That is, in the fixed frame 70 in this first modified example, the other end in the extending direction of the base 71 (the end close to the inner cylinder 100) is fixed to the upper outer surface of the second inner cylinder portion 106 by welding. This welded portion is referred to as a "welded portion P." In addition, the joint side flange 112 is fixed to the lower end outer surface of the second inner cylinder portion 106 by welding.

[0162] The base 71 and the fixed portion 73 of the fixed frame 70 are connected to the joint side flange 112 by a thin plate-like rib 77. A gap 75 is formed between the rib 77 and the second inner cylinder portion 106.

[0163] Moreover, the outer surface of one axial end of the first inner cylindrical portion 105 is fixed to the cylindrical body 80a by welding.

[0164] On the other hand, the other end of the base 81 of the fixed frame 80 in the extending direction is fixed to the outer surface of the lower end of the cylindrical body 80a by welding. Also, the joint side flange 112 is fixed to the outer surface of the upper end of the cylindrical body 80a by welding.

[0165] The base 81 and the fixed portion 83 of the fixed frame 80 are connected to the joint-side flange 112 by a thin plate-like rib 87. A gap 85 is formed between the rib 87 and the cylindrical body 80a.

[0166] The other axial end of the piping member 101, covered with the gasket 102, is clamped between the fixing portion 73 of the fixing frame 70 arranged in contact with its inner surface, the pressing plate 112a arranged on the outer surface, and the approximately L-shaped bolt holder 90 arranged on the outside of that, and is then tightened and fixed with a bolt 61 and a nut 62.

[0167] In addition, one axial end of the piping member 101 covered with the gasket 102 is clamped between the fixing portion 83 of the fixing frame 80 abutting against its inner surface, the pressing plate 112a abutting against its outer surface, and the bolt holder 90 arranged on the outside of that, and is then tightened and fixed with a bolt 61 and a nut 62.

[0168] Furthermore, by inserting a shipping bolt 110 into a bolt insertion hole (not shown) of a pair of bolt holders 90, 90 and tightening and fixing it with a plurality of nuts 111, the piping member 101 is stretched to a predetermined second designated length L2 and is positioned in a tensioned state.

[0169] In the expansion joint 10F of the first modified example, the same effects as those of the expansion joint 10E shown in Fig. 13 can be obtained (see paragraphs 0157 and 0158). Furthermore, even if fluids such as rainwater or powders such as dust accumulate on the bases 71, 81 of the fixed frames 70, 80, the gaps 75, 85 formed between the ribs 77 and the erected portions 106b of the second inner cylinder portion 106 and the gaps 85 formed between the ribs 87 and the cylindrical body 80a allow the fluids and powders to be discharged from the gaps 75, 85, thereby suppressing deterioration of the piping members 101, etc.

[0170] FIG. 15 shows a second modified example of the expansion joint of the third embodiment.

[0171] The expansion joint 10G of this second modified example basically has the same structure as the shape shown in FIG. 14, but the structure of the second inner cylindrical portion 106 is slightly different.

[0172] That is, the erected portion 106b of the second inner cylinder portion 106 in this second modified example extends longer than the erected portion 106b in Fig. 14, and the overlap amount (lap amount) of the second inner cylinder portion 106 with respect to the first inner cylinder portion 105 is greater than in Fig. 13. This structure is similar to the expansion joint 10C of the second modified example in the second embodiment shown in Fig. 11.

[0173] Furthermore, in the expansion joint 10G of this second modified example, it is possible to obtain the same effect as the expansion joint 10E shown in FIG. 13 (see paragraphs 0157 and 0158), and by providing the long upright portion 106b in the second inner tube portion 106, it is possible to suppress the intrusion of foreign matter into the gap K between the inner tube 100 and the piping member 101, making it difficult for cracks, fissures, etc. to occur in the piping member 101.

[0174] FIG. 16 shows a third modified example of the expansion joint of the third embodiment.

[0175] 15, but has a structure in which a dustproof member 107 is inserted between the first inner cylinder portion 105 and the second inner cylinder portion 106, and the gap (lower opening) between the first inner cylinder portion 105 and the erected portion 106b of the second inner cylinder portion 106 is closed. This structure is similar to the expansion joint 10D of the third modified example in the second embodiment shown in FIG.

[0176] In the expansion joint 10H of this third modified example, the dustproof member 107 arranged between the first inner tube portion 105 and the second inner tube portion 106 can prevent foreign matter from entering between the inner tube 100 and the piping member 101.

[0177] Furthermore, since a communication hole 74 that communicates with the gap K between the inner tube 100 and the piping member 101 is formed in the fixed frame 70, even if foreign matter such as dust is present in the gap K between the inner tube 100 and the piping member 101 due to, for example, the material of the dustproof member 107 (for example, depending on the material of the filling member, it may protrude from the outer periphery of the dustproof member), the foreign matter can be discharged from the communication hole 74, thereby making it difficult for cracks, fissures, etc. to occur in the piping member 101.

[0178] (Fourth embodiment of expansion joint) A fourth embodiment of the expansion joint according to the present invention is shown in Fig. 17. Note that parts that are substantially the same as those in the above-mentioned embodiment are given the same reference numerals and the description thereof will be omitted.

[0179] The expansion joint 10I of the fourth embodiment has a structure in which a piping member 101 is directly stretched between a pair of opposing ducts 4, 5. The pair of ducts 4, 5 have the same outer diameter.

[0180] Then, the inner surface side of one axial end of the piping member 101 covered with the gasket 102 is clamped and fixed by the fixing band 95 arranged on the outer surface side with the piping member 101 abutting against the duct 4, and the inner surface side of the other axial end of the piping member 101 covered with the gasket 102 is clamped and fixed by the fixing band 95 arranged on the outer surface side with the duct 5 abutting against the piping member 101. As a result, the piping member 101 is stretched to the predetermined second specified length L2 and is arranged in a tensioned state.

[0181] When installing the piping member 101 as described above, the piping member 101 can be stretched in advance by the force of an operator or by a predetermined jig, tool, device, etc., to give it tension, and then fixed with a fixing band 95.

[0182] Furthermore, when a stud bolt or a hooking member is present (such as when the bolt 61 is a stud bolt in the embodiment shown in Figure 18 described later), this can be used to hook one end or the other end of the piping member 101, thereby making the stretching work of the piping member 101 more efficient.

[0183] In the expansion joint 10I of the fourth embodiment, there is no need to provide a flange for fixing the expansion joint on the vibrating sieve or duct side, so that the structure can be simplified.

[0184] (Fifth embodiment of expansion joint) A fifth embodiment of the expansion joint according to the present invention is shown in Fig. 18. Note that parts that are substantially the same as those in the above-mentioned embodiment are given the same reference numerals and the description thereof will be omitted.

[0185] The expansion joint 10J of the fifth embodiment is basically similar to the expansion joint 10I of the fourth embodiment in that a piping member 101 is stretched between a pair of ducts 4, 5. However, it differs from the fourth embodiment in that both axial ends of the piping member 101 are fastened and fixed by bolts 61 and nuts 62 via pressure plates 112a.

[0186] The expansion joint 10J of the fifth embodiment can also provide the same advantageous effects as those of the fourth embodiment.

[0187] (Sixth embodiment of the expansion joint) A sixth embodiment of the expansion joint according to the present invention is shown in Fig. 19. Note that parts that are substantially the same as those in the above-mentioned embodiment are given the same reference numerals and the description thereof will be omitted.

[0188] The expansion joint 10K of the sixth embodiment has a structure in which an inner cylinder 100 and a piping member 101 are arranged via a holder 98 that holds a shipping bolt 110 and a fixing member 99.

[0189] Each fixing member 99 is generally in the shape of an L-shape and includes a base 99a and a bent portion 99b that is bent perpendicularly from one end of the base 99a. Of the pair of fixing members 99, 99, the inner surface of one end of the base 99a of the fixing member 99 located at the upper part of the drawing is fixed to the outer surface of the end of the inner cylinder 100 by welding or the like.

[0190] Further, each holder 98 that holds the shipping bolt 110 is fixed to the bent portions 99b, 99b of the pair of fixing members 99, 99 by welding.

[0191] One axial end of the piping member 101 covered with the gasket 102 is clamped between a base 99a of the fixing member 99 located at the upper part of the drawing and a pressing plate 112a, and is then fastened and fixed with a bolt 61 and a nut 62. In addition, a gasket 102a, which is separate from the gasket 102, is disposed between a bent portion 99b of the fixing member 99 and the flange 210, and the gasket 102a is clamped and fixed between the bent portion 99b and the flange 210.

[0192] Similarly, the other axial end of the piping member 101 covered with the gasket 102 is clamped between a base 99a of the fixing member 99 located at the bottom of the drawing and a pressing plate 112a, and is then fastened and fixed with a bolt 61 and a nut 62. In addition, a gasket 102a is disposed between a bent portion 99b of the fixing member 99 and a flange 214, and the gasket 102a is clamped and fixed between the bent portion 99b and the flange 214.

[0193] Furthermore, both axial ends of the shipping bolt 110 are inserted into bolt insertion holes (not shown) formed in a pair of upper and lower holders 98, 98, and are tightened and fixed with a plurality of nuts 111, so that the piping member 101 is stretched to a predetermined second designated length L2 and is positioned in a tensioned state.

[0194] (Seventh embodiment of the expansion joint) A seventh embodiment of the expansion joint according to the present invention is shown in Fig. 20. Note that parts that are substantially the same as those in the above embodiment are given the same reference numerals and their explanation will be omitted.

[0195] An expansion joint 10L in the seventh embodiment differs from the previous embodiments in the structures of a piping member 120 and ducts 6, 7.

[0196] More specifically, the seventh embodiment has a double-tube duct structure in which a duct 6 having a predetermined inner diameter and a duct 7 having an inner diameter smaller than that of the duct 6 are inserted and disposed in the radial center of the duct 6. The other axial end of the duct 7 is inserted into the duct 6 and overlaps with it by a predetermined length.

[0197] In addition, piping member 120 is capable of covering the upper openings of ducts 6, 7 and has an annular base 121 extending in a direction perpendicular to the axis of ducts 6, 7, a tubular fixing portion 122 hanging down from the radial inner peripheral edge of annular base 121, and a tubular fixing portion 123 hanging down from the radial outer peripheral edge of annular base 121.

[0198] Furthermore, the outer periphery of the cylindrical fixing parts 122, 123 of the piping member 120 is covered so as to be wrapped with gaskets 102, 102.

[0199] Then, the cylindrical fixing portion 122 of the piping member 101, covered with the gasket 102, is clamped between the duct 7 arranged against its inner surface and the pressing plate 130 arranged on the outer surface, and is fastened and fixed with a bolt 61 and a nut 62.

[0200] Similarly, the cylindrical fixing portion 123 of the piping member 101, covered with the gasket 102, is clamped between the duct 6 arranged in abutment against its inner surface and the pressure plate 130 arranged on the outer surface, and is tightened and fixed with a bolt 61 and a nut 62.

[0201] As a result, the piping member 120 is stretched to the predetermined second designated length L2 and placed in a tensioned state.

[0202] The expansion joint 10L of the seventh embodiment can also be installed to accommodate the ducts 6, 7 having a double cylindrical shape.

[0203] Although the annular base 121 of the piping member 120 has a shape that expands in a direction perpendicular to the axis of the ducts 6 and 7, it may have a shape that expands at an angle to the axis of the ducts 6 and 7.

[0204] (Eighth embodiment of the expansion joint) An eighth embodiment of the expansion joint according to the present invention is shown in Fig. 21. Note that parts that are substantially the same as those in the above-mentioned embodiment are given the same reference numerals and the description thereof will be omitted.

[0205] An expansion joint 10M in the eighth embodiment basically has the same structure as the expansion joint 10F shown in FIG. 14, but the shape of the fixed frame 80A is different from that in FIG.

[0206] That is, the fixed frame 80A in this eighth embodiment has an angle shape consisting of a base 81a that slopes diagonally downward from the outer surface of the lower end of the cylindrical body 80a toward the radially outward direction of the inner tube 100, and a fixed portion 83a that hangs down from one end of the base 81a in the extension direction.

[0207] In addition, an outer upper edge 87b of a thin plate-like rib 87a that connects the base 81a of the fixed frame 80A and the joint-side flange 112 is tapered obliquely downward toward the outside in the radial direction of the inner cylinder 100. A gap 85 is formed between the rib 87a and the cylindrical body 80a.

[0208] In addition, in this expansion joint 10M, it is possible to obtain the same effects as those of the expansion joint 10F shown in FIG. 14 (see paragraph 0169).

[0209] Furthermore, even if fluids such as rainwater or powder such as dust accumulate on the base 81a of the fixed frame 80A, the base 81a has a shape that slopes diagonally downward toward the radially outward direction of the inner tube 100, so that the fluids, powder, etc. can flow over the base 81a and be discharged in a direction away from the inner tube 100. The fluids, powder, etc. can also be discharged from the gaps 85, thereby suppressing deterioration of the inner tube 100, piping members 101, etc.

[0210] 21, the base portion 71 of the fixed frame 70 may be shaped to be inclined obliquely upward toward the outside in the radial direction of the inner cylinder 100. As shown in FIG.

[0211] In this embodiment, when powder such as dust contained in the fluid accumulates on the base 71 of the fixed frame 70, the fluid, powder, etc. flow over the base 71 due to its own weight or the vibration of the vibrating sieve, and can be discharged through the gap 75 between the first inner tube portion 105 and the second inner tube portion 106, thereby suppressing deterioration of the piping components 101, etc.

[0212] (Durability test) Tests on the durability of the expansion joint of this embodiment will be described below.

[0213] (Type of shape) The installation methods of the outermost sealing layer 113 and the shapes of the outermost sealing layer 113 as shown below were designated as types 1 to 6.

[0214] (Type 1, this embodiment) As shown in Fig. 3A, the type 1 expansion joint 10 is formed in a substantially cylindrical shape with a height of a first designated length L1. The first designated length L1 is 50 to 100% of the length calculated by subtracting the vibration amplitude from the second designated length L2. As shown in Fig. 3B, the expansion joint 10 is installed so that it is connected to the vibrating sieve and the duct in a state where the length of the expansion joint 10 or the outermost seal layer 113 is stretched to the second designated length L2.

[0215] (Type 2: A type with extra length that takes into account the expansion and contraction range of vibration) A type 2 expansion joint is formed in a roughly torus shape as shown in FIG. 4, and is manufactured so that the length of the outermost seal layer 113 is longer than the distance between the installation surfaces (for example, when the distance between the installation surfaces is 100 mm to 500 mm, the length of the outermost seal layer 113 is 20% longer than the distance between the installation surfaces), and is installed by being shortened to the distance between the installation surfaces.

[0216] (Type 3: Drum-shaped with the center inflated) As shown in FIG. 5, in a type 3 expansion joint, the outermost seal layer 113 is formed in a shape consisting of an upper part that is approximately shaped like the side surface of a circular truncated cone, a middle part that is approximately shaped like a torus, and a lower part that is approximately shaped like the side surface of a circular truncated cone, and the length of the outermost seal layer 113 is manufactured to be longer than the distance between the installation surfaces (for example, when the distance between the installation surfaces is 100 mm to 500 mm, the length of the outermost seal layer 113 is 20 to 40% longer than the distance between the installation surfaces), and the expansion joint is installed by being shortened to the distance between the installation surfaces.

[0217] (Type 4: Lantern-shaped with the center part protruding outwards) As shown in FIG. 6, a type 4 expansion joint has an outermost seal layer 113 in a shape that is approximately a biconical side surface, and is formed in a shape such that the differential coefficient of the average rate of change of the inner diameter of the approximately biconical truncated side surface takes a positive value. The length of the outermost seal layer 113 is longer than the installation surfaces (for example, when the installation surfaces are 100 mm to 500 mm apart, the length of the outermost seal layer 113 is 20 to 40% longer than the installation surfaces), and the joint is installed by being shortened to the installation surfaces.

[0218] (Type 5: Bellows type) As shown in FIG. 7, the type 5 expansion joint has an outermost seal layer 113 that is shaped as a plurality of units each consisting of a concave portion shaped like a substantially truncated cone side and a convex portion shaped like a substantially torus body, and is formed into a substantially bellows shape in which the units are arranged at substantially equal intervals in the substantially vertical direction. The length of the outermost seal layer 113 is longer than the distance between the installation surfaces (for example, when the distance between the installation surfaces is 100 mm to 500 mm, the length of the outermost seal layer 113 is 20 to 40% longer than the distance between the installation surfaces), and the joint is installed by being shortened to the distance between the installation surfaces.

[0219] (Type 6: No extra length) The type 6 expansion joint was manufactured so that the length of the outermost sealing layer 113 was the length between the installation surfaces, as shown in FIG.

[0220] Example 1 An expansion joint was produced using earthquake-resistant silicone rubber with a hardness (Hs) of 40, tear strength of 52 (kN / m), elongation of 700 (%), and tensile strength of 11.3 (MPa) as the material for the outermost sealing layer 113, glass felt as the material for the elastic layer, and glass cloth as the material for the inner skin layer.

[0221] Example 2 The outermost seal layer 113 was made of silicone rubber with a hardness (Hs) of 52, tear strength of 15 (kN / m), elongation of 550 (%), and tensile strength of 10 (MPa), and the expansion joint was manufactured under the same manufacturing conditions as in Example 1.

[0222] Example 3 The outermost seal layer 113 was made of silicone rubber with a hardness (Hs) of 32, tear strength of 18 (kN / m), elongation of 650 (%), and tensile strength of 6.5 MPa, and the expansion joint was manufactured under the same manufacturing conditions as in Example 1.

[0223] Example 4 The outermost sealing layer 113 was made of high-tear silicone rubber with a hardness (Hs) of 45, tear strength of 40 (kN / m), elongation of 600 (%), and tensile strength of 10 MPa, and the expansion joint was manufactured under the same manufacturing conditions as in Example 1.

[0224] Example 5 The outermost sealing layer 113 was made of high-elongation silicone rubber with a hardness (Hs) of 36, tear strength of 32 (kN / m), elongation of 940 (%), and tensile strength of 10.9 MPa, and the expansion joint was manufactured under the same manufacturing conditions as in Example 1.

[0225] Example 6 An expansion joint was produced under the same production conditions as in Example 1 using urethane rubber with hardness (Hs) of 32, tear strength of 13 (kN / m), elongation of 610 (%), and tensile strength of 11.4 MPa as the material for the outermost seal layer 113.

[0226] Example 7 An expansion joint was produced under the same production conditions as in Example 1 using chloroprene rubber with hardness (Hs) of 45, tear strength of 15 (kN / m), elongation of 400 (%) and tensile strength of 5.5 MPa as the material for the outermost seal layer 113.

[0227] Example 8 An expansion joint was manufactured under the same manufacturing conditions as in Example 1 using silicone-modified EPDM rubber with hardness (Hs) of 41, tear strength of 12 (kN / m), elongation of 930 (%), and tensile strength of 6.2 MPa as the material for the outermost sealing layer 113.

[0228] Comparative Example 1 The expansion joint of Comparative Example 1 was manufactured under the same manufacturing conditions as Example 1, using low-hardness, high-elongation silicone rubber with a hardness (Hs) of 23, a tear strength of 10 (kN / m), an elongation percentage of 770 (%), and a tensile strength of 5 MPa as the material for the outermost sealing layer 113.

[0229] Comparative Example 2 The expansion joint of Comparative Example 2 was manufactured under the same manufacturing conditions as Example 1, using silicone rubber with a hardness (Hs) of 58, tear strength of 35 (kN / m), elongation of 680 (%), and tensile strength of 9.2 MPa as the material for the outermost seal layer 113.

[0230] Comparative Example 3 The expansion joint of Comparative Example 3 was manufactured under the same manufacturing conditions as Example 1, using silicone rubber with a hardness (Hs) of 51, tear strength of 7 (kN / m), elongation of 400 (%), and tensile strength of 8.7 MPa as the material for the outermost seal layer 113.

[0231] Comparative Example 4 The expansion joint of Comparative Example 4 was manufactured under the same manufacturing conditions as Example 1 using urethane rubber with a hardness (Hs) of 90, a tear strength of 109 (kN / m), an elongation of 510 (%), and a tensile strength of 59 MPa as the material for the outermost seal layer 113.

[0232] Comparative Example 5 The expansion joint of Comparative Example 5 was manufactured under the same manufacturing conditions as Example 1 using silicone rubber with a hardness (Hs) of 43, tear strength of 15 (kN / m), elongation of 370 (%), and tensile strength of 6.5 MPa as the material for the outermost seal layer 113.

[0233] Comparative Example 6 The expansion joint of Comparative Example 6 was manufactured under the same manufacturing conditions as Example 1 using silicone rubber with a hardness (Hs) of 20, tear strength of 17 (kN / m), elongation of 1030 (%), and tensile strength of 5.7 MPa as the material for the outermost seal layer 113.

[0234] Comparative Example 7 The expansion joint of Comparative Example 7 was manufactured under the same manufacturing conditions as Example 1 using silicone rubber with a hardness (Hs) of 31, tear strength of 15 (kN / m), elongation of 480 (%), and tensile strength of 4.7 MPa as the material for the outermost seal layer 113.

[0235] Comparative Example 8 The expansion joint of Comparative Example 8 was manufactured under the same manufacturing conditions as Example 1 using urethane rubber with a hardness (Hs) of 50, tear strength of 29 (kN / m), elongation of 610 (%), and tensile strength of 26.6 MPa as the material for the outermost seal layer 113.

[0236] Comparative Example 9 The outermost sealing layer 113 was made of a material in which a meta-aramid fiber sheet was coated with silicone rubber, and the expansion joint of Comparative Example 9 was produced under the same production conditions as in Example 1, except that Shape 1 was Type 2.

[0237] Comparative Example 10 The outermost sealing layer 113 was made of a material in which a meta-aramid fiber sheet was coated with silicone rubber, and the expansion joint of Comparative Example 10 was made under the same manufacturing conditions as in Example 1, except that the shape 1 was type 3.

[0238] Comparative Example 11 The outermost sealing layer 113 was made of a material in which a meta-aramid fiber sheet was coated with silicone rubber, and the expansion joint of Comparative Example 11 was made under the same manufacturing conditions as in Example 1, except that the shape 1 was Type 4.

[0239] Comparative Example 12 The outermost sealing layer 113 was made of a material in which a meta-aramid fiber sheet was coated with silicone rubber, and the expansion joint of Comparative Example 12 was made under the same manufacturing conditions as in Example 1, except that the shape 1 was Type 5.

[0240] Comparative Example 13 The expansion joint of Comparative Example 13 was produced under the same production conditions as in Example 1, except that the outermost sealing layer 113 was a polytetrafluoroethylene (PTFE) sheet having a thickness of 0.3 mm and the shape 1 was type 6.

[0241] The vibration-resistant silicone rubber used in Example 1 was (product name: ST-Silicone, manufactured by Shibata Kogyosho Co., Ltd.), the silicone rubber used in Example 2 was (product name: KE-552-U, manufactured by Shin-Etsu Chemical Co., Ltd.), the silicone rubber used in Example 3 was (product name: KE-503-U, manufactured by Shin-Etsu Chemical Co., Ltd.), the high tear silicone rubber used in Example 4 was (product name: SFG Silicon, manufactured by Sanshin Enterprise Co., Ltd.), the high elongation silicone rubber used in Example 5 was (product name: Highly elongated silicone rubber, manufactured by Kyowa Kogyo Co., Ltd.), the urethane rubber used in Example 6 was (product name: RC-3030, manufactured by Ritsusei Chemical Industry Co., Ltd.), the chloroprene rubber used in Example 7 was (product name: 45A, manufactured by Misumi Corporation), and the silicone-modified EPDM rubber used in Example 8 was (product name: SEP-1421-U, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0242] In addition, the low hardness, high elongation silicone rubber of Comparative Example 1 is (product name: KE-520-U, manufactured by Shin-Etsu Chemical Co., Ltd.), the silicone rubber of Comparative Example 2 is (product name: KE-7212-U, manufactured by Shin-Etsu Chemical Co., Ltd.), the silicone rubber of Comparative Example 3 is (product name: general silicone rubber, manufactured by Kyowa Rubber Industry Co., Ltd.), the urethane rubber of Comparative Example 4 is (product name: Urethane Rubber 90°, manufactured by Misumi Corporation), the silicone rubber of Comparative Example 5 is (product name: KE-941-U, manufactured by Shin-Etsu Chemical Co., Ltd.), the silicone rubber of Comparative Example 6 is (product name: low hardness silicone rubber, manufactured by Kyowa Rubber Industry Co., Ltd.), the silicone rubber of Comparative Example 7 is (product name: KE-931-U, manufactured by Shin-Etsu Chemical Co., Ltd.), and the urethane rubber of Comparative Example 8 is (product name: Ti-Plen, manufactured by Tigers Polymer Corporation).

[0243] Furthermore, the glass felt is heat-resistant glass filt B No. 7740 (product name: manufactured by A & A Material Co., Ltd.), the glass cloth is Suntex No. 1910 (product name: manufactured by A & A Material Co., Ltd.), and the gasket is rubber-coated tape No. 4100 (product name: manufactured by A & A Material Co., Ltd.).

[0244] The hardness of the outermost seal layer 113 of each Example and Comparative Example was measured according to the JIS K6253:2012 test method using a type A durometer. The tear strength was measured using a crescent-shaped test piece according to the JIS K6252:2015 test method. The elongation and tensile strength were measured using a dumbbell-shaped test piece according to the JIS K6251:2017 test method. Each test was measured while maintaining the temperature at 23°C.

[0245] (Evaluation method) When the expansion joints 10 were installed in the arrangement shown in Figures 1 and 2 and the vibrating sieve 20 was driven continuously for 8 hours per day, rupture and damage occurred in Comparative Examples 1 to 13, but no damage occurred even after 180 days in Examples 1 to 9. Table 1 shows the configuration of the outermost seal layer 113 of each Example and Comparative Example and the number of days until rupture. [Table 1]

[0246] The present invention has been specifically described above with reference to the preferred embodiments of the present invention. However, it is obvious that those skilled in the art may adopt modified forms based on the technical concepts and teachings of the present invention. [Explanation of symbols]

[0247] 1,3 Duct 10,11,10A,10B,10C,10D,10E,10F,10G,10H,10J,10K,10L,10M Expansion joint 20 Vibrating sieve 50,51 Fixing member 53 Fixed part 55 Overhang 70 Fixed Frame 74 Communication hole 100 inner cylinder 101 Piping components 103 First flange 104 Second flange 105 First inner cylinder 106 Second inner cylinder 113 Outermost sealing layer 114 Elastic layer 115 Endothelial layer

Claims

1. An expansion joint installed at a joint between a vibrating sieve and a duct, An inner cylinder; a cylindrical piping member disposed on the outside of the inner cylinder and having a single-layer or multiple-layer structure; The outermost layer of the piping member is formed from a material having a hardness in the range of 30 Hs to 55 Hs, a tensile strength in the range of 5 MPa to 20 MPa, an elongation in the range of 400% to 1000%, and a tear strength in the range of 10 kN / m to 100 kN / m.

2. The expansion joint according to claim 1, The piping member is configured by laminating an inner skin layer, an elastic layer, and an outermost sealing layer in this order from the inside, The expansion joint is formed of a material having a hardness in the range of 30Hs to 55Hs, a tensile strength in the range of 5MPa to 20MPa, an elongation in the range of 400% to 1000%, and a tear strength in the range of 10kN / m to 100kN / m.

3. The expansion joint according to claim 1 or 2, The apparatus further includes a pair of flanges that are installed at both ends of the piping member in the central axis direction and are fixed to the vibrating sieve and the duct, respectively, The inner tube is fixed to each of the pair of flanges and is composed of a first inner tube portion and a second inner tube portion that are relatively displaceable, and the first inner tube portion and the second inner tube portion are arranged so as to partially oppose each other in a direction perpendicular to the central axis direction of the expansion joint.

4. The expansion joint according to claim 2, The expansion joint is formed of a material having a hardness in the range of 30Hs to 45Hs, a tensile strength in the range of 10MPa to 20MPa, an elongation in the range of 600% to 800%, and a tear strength in the range of 45kN / m to 65kN / m.

5. The expansion joint according to claim 3, The first inner cylinder portion has a shape in which the diameter gradually decreases from one end to a middle portion in a central axis direction of the piping member, and then the diameter is constant from the middle portion to the other end, An expansion joint, wherein the second inner cylinder portion has a shape having a constant diameter about a central axis of the piping member.

6. The expansion joint according to claim 1, a pair of fixing members for fixing both ends of the piping member in a central axis direction to the vibrating sieve and the duct, respectively; Each fixing member is A fixing portion that fixes the end portion of the piping member; The expansion joint has a protruding portion that protrudes radially outward from the piping member while being bent or curved from the fixed portion in a direction approaching the mating fixed member.

7. The expansion joint according to claim 1, a fixing frame for fixing the other end of the piping member in the central axis direction to the duct, The fixed frame is an expansion joint having a communication hole formed therein that communicates with the gap between the inner tube and the piping member.

8. A method for installing the expansion joint according to claim 1 at a joint between a vibrating screen and a duct, comprising the steps of: Fixing the expansion joint, which is manufactured to have a first specified length in a central axis direction, to each of the vibrating sieve and the duct; applying a force to the expansion joint such that the expansion joint is maintained in an expanded state at a second designated length that is longer than the first designated length; releasing the force from the expansion joint; a state of the expansion joint after the step of releasing the force includes a state in which the expansion joint changes from the second designated length to a third designated length that is at least longer than the first designated length.

9. A method for installing the expansion joint according to claim 3 at a joint between a vibrating screen and a duct, comprising the steps of: a step of fixing the expansion joint, which is manufactured to have a first specified length in a central axis direction, to the vibrating sieve and the duct, respectively, by each of the pair of flanges; applying a force between the pair of flanges such that the expansion joint is maintained in an expanded state at a second designated length that is longer than the first designated length; and releasing the force from the pair of flanges. a state of the expansion joint after the step of releasing the force includes a state in which the expansion joint changes from the second designated length to a third designated length that is at least longer than the first designated length.

10. The method for installing an expansion joint according to claim 8 or 9, The method for installing an expansion joint, wherein the first specified length is 50% to 100% of a length calculated by subtracting a vibration amplitude of the vibrating sieve from the second specified length.

Images