Separation prevention structure of pipe connection portion

Abstract

To surely prevent separation movement of a spigot and a socket with respect to a collar while improving a separation force absorption capacity, and to keep a bent state of the spigot and a pipe supporting portion of the collar within a proper range.SOLUTION: A separation prevention structure of a pipe connection portion comprises: a collar 30 which has a split structure surrounding a fitting connection portion 20 between a spigot 1A and a socket 2A in a sealed state, and which is externally mounted; a first separation prevention portion which permits the socket 2A and the spigot 1A to perform relative separation movement up to a position that brings them into a separation state where they are disconnected from each other while preventing the socket 2A and the collar 30 from performing relative separation movement at and exceeding a fixed level in the separation state, and which is disposed on a region where the collar 30 and a socket side of the other pipe portion are relatively opposed to each other in a pipe axial direction; a second separation prevention portion 5 which includes a lock portion 55 for increasing locking resistance with respect to an outer peripheral face 1a of the spigot 1A in accordance with the separation movement of the spigot 1A, and which is disposed at a pipe supporting portion 30d side at one end side of the collar 30; and an inclination restriction portion 9 which restricts inclination of the spigot 1A with respect to the pipe supporting portion 30d at the one end side of the collar 30 in the separation state, and which is disposed in the collar 30.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a structure for preventing separation of a pipe connection part, in which a joint ring of a split structure that surrounds in a sealed manner the mating connection part between the insertion port of one pipe part and the receiving port of the other pipe part is fitted over both pipe parts. [Background technology]

[0002] As a structure for preventing the above-mentioned pipe connection from coming off, there is a pipe installation structure shown in Patent Document 1. In this pipe installation structure, the fitting connection between the insertion port of one pipe part and the receiving port of the other pipe part is composed of a K-shaped mechanical joint. In this mechanical joint, a sealant such as a rubber ring is attached between the outer peripheral surface of the insertion port and the tapered inner peripheral surface of the receiving port. The flange part of the press ring, which has a pressing part that can press this sealant from the pipe axis direction, and the flange part of the receiving port are tightened and connected with bolts and nuts. By this tightening connection, the sealant is compressed to a watertight state by the pressing part of the press ring, which is drawn and fixed to the flange part of the receiving port, and the watertight state is maintained.

[0003] In addition, the connecting ring of a split structure that surrounds the mechanical joint, which is the mating connection part, in a sealed state has as its main components a cylindrical peripheral wall portion having a larger diameter than the receiving port, annular side wall portions extending radially inwardly from both ends of the peripheral wall portion in the pipe axial direction, and pipe support portions extending integrally outwardly along the pipe axial direction from the inner diameter side ends of each side wall portion. The inner peripheral surfaces of both pipe support parts of the collar are provided with seal parts fitted with a seal material that seals between the inner peripheral surfaces of both pipe parts.

[0004] Furthermore, a separation movement prevention means is provided at a location where the collar and the socket side of the other pipe section face each other in the pipe axial direction, which abuts to prevent the socket and the collar from moving apart relative to each other beyond a certain level. The separation movement prevention means is configured such that the inner diameter of the pipe support part on the other end side of the collar that is the socket side is smaller than the maximum outer diameter of the tapered part of the socket. When the spigot and the socket are separated from each other, the pipe support part on the other end side of the collar abuts against the tapered part of the socket from the pipe axial direction to prevent further separation.

[0005] In addition, a separation prevention part having a split structure and equipped with a locking member that bites into the outer peripheral surface is clamped and fixed to the outer peripheral surface of the insertion port located within the joint ring, and the outer diameter of this separation prevention part is formed to be larger than the inner diameter of the pipe support part on one end side of the joint ring that is on the insertion port side.When the insertion port and the receiving port are separated, the separation prevention part clamped and fixed to the insertion port abuts against the pipe support part on one end side of the joint ring from the pipe axial direction, preventing further separation movement. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2016-138637 A Summary of the Invention [Problem to be solved by the invention]

[0007] In the pipe mounting structure shown in Patent Document 1, when the spigot and the socket are separated, the separation prevention part clamped and fixed to the spigot only abuts against the pipe support part on one end of the collar from the pipe axial direction, and does not have the function of preventing bending between the spigot and the pipe support part on one end of the collar. Therefore, when the spigot and the socket are separated, the spigot and the pipe support part on one end of the collar bend significantly, causing a localized decrease in the circumferential sealing ability of the seal part provided on the inner surface of the pipe support part on one end of the collar, resulting in the inconvenience of fluid leakage from the area where the sealing ability has decreased.

[0008] In view of this situation, the main object of the present invention is to provide a pipe connection prevention structure which reliably prevents the insertion and receiving ports from moving away from the collar while improving the absorption capacity against removal forces, and which maintains the bending state between the insertion port and the pipe support portion on one end side of the collar within an appropriate range, thereby suppressing fluid leakage caused by localized deterioration of the seal in the circumferential direction of the seal portion. [Means for solving the problem]

[0009] The first characteristic configuration of the present invention is that a joint ring of a split structure which surrounds in a sealed state the fitting connection portion between the insertion port of one pipe section and the receiving port of the other pipe section is fitted over both pipe sections, and a first removal prevention portion is provided at the portion facing the insertion port and the receiving port of the other pipe section in the pipe axial direction which allows relative removal movement up to a separated state in which the receiving port and the insertion port are disconnected, and which abuts and prevents relative removal movement between the receiving port and the joint ring beyond a certain level in the separated state, a second removal prevention portion is provided on the pipe support portion side of one end side of the joint ring in the pipe axial direction, the second removal prevention portion is provided with a removal prevention portion which increases the removal resistance between the outer peripheral surface of the insertion port as the insertion port moves away from the pipe, and a tilt restriction portion is provided within the joint ring which restricts tilting of the insertion port relative to the pipe support portion on one end side of the joint ring in the separated state.

[0010] According to the above configuration, when a separation force due to an earthquake, uneven settlement, or the like acts on the fitting connection between the spigot and the socket, the first removal prevention portion provided at the portion facing the spigot and the socket side of the other pipe section in the pipe axial direction allows the socket and the socket to move relative to each other until they are in a separated state in which they are disconnected. This makes it possible to absorb a large removal force acting on the fitting connection between the spigot and the socket. At the same time, it is possible to reliably prevent the socket and the spigot from moving relative to each other beyond a certain level in the separated state, so the socket will not come out of contact with the pipe support portion on the other end of the spigot.

[0011] In addition, the anti-detachment portion of the second prevention portion provided on the pipe support portion side of one end of the joint ring in the pipe axial direction increases in resistance to detachment between the outer peripheral surface of the insertion port as the insertion port moves away from the pipe support portion on one end of the joint ring, so that, overall, the insertion port of one pipe portion and the pipe support portion on one end of the joint ring are firmly fixedly connected together via the second prevention portion. This makes it possible to firmly prevent the receiving port from moving out of the pipe support portion on the other end of the collar, and the insertion port from moving out of the pipe support portion on one end of the collar, even if the insertion port and the receiving port become separated.

[0012] Furthermore, when the spigot and the socket are separated, even if a bending force due to an earthquake or uneven force due to fluid pressure acts on the spigot, the tilt restricting portion provided in the collar can restrict the tilt of the spigot relative to the pipe support portion on one end of the collar. This keeps the bending state between the spigot and the pipe support portion on one end of the collar within an appropriate range in the separated state, thereby suppressing fluid leakage due to localized deterioration of the sealing ability in the circumferential direction of the seal portion.

[0013] Therefore, the relative movement of the insertion port and the socket to the disengaged state where the connection is released improves the ability to absorb the disengagement force acting on the fitting connection. And yet, when the insertion port and the socket have moved to the disengaged state, the cooperation of the first and second disengagement prevention parts reliably prevents further disengagement, preventing leakage of fluid. Moreover, the bending state between the insertion port and the pipe support part on one end of the collar in the disengaged state is maintained within an appropriate range, preventing leakage of fluid due to localized deterioration of sealing in the circumferential direction of the seal part.

[0014] The second characteristic configuration of the present invention is that the tilt regulating portion is provided with a tilt regulating body of a split structure that is attached to the insertion port when the receiving port and the insertion port are mated and connected and when they are separated, and that has a tilt regulating surface that can abut against the outer surface of the insertion port that tilts in the separated state, and a fixed connecting portion that fixedly connects the tilt regulating body to the receiving port.

[0015] According to the above configuration, when the socket and the insertion port are fitted and connected, the tilt regulating body of the split structure of the tilt regulating part is fitted on the insertion port, and the tilt regulating body is fixedly connected to the socket by the fixed connection part. Even when the socket and the insertion port move relative to each other to the detached state due to an earthquake, uneven settlement, etc., the tilt regulating body is maintained in a state of being fitted on the insertion port. Therefore, when a bending force due to an earthquake or uneven force due to fluid pressure acts in the detached state, the tilt regulating surface of the tilt regulating body fixedly connected to the socket abuts against the outer surface of the insertion port. This reliably maintains the bending state between the insertion port and the pipe support part on one end side of the collar in the detached state within an appropriate range, and it is possible to suppress leakage of fluid due to a localized decrease in sealing performance in the circumferential direction of the seal part.

[0016] A third characteristic feature of the present invention is that the tilt regulating body is provided with a tilt regulating protrusion that comes into contact with the inner surface of the joint ring as the insertion port tilts in the detached state.

[0017] According to the above configuration, when bending force due to an earthquake or uneven force due to fluid pressure is applied in the detached state, the tilt restriction surface of the tilt restriction body fixedly connected to the socket comes into contact with the outer surface of the insertion port, and the tilt restriction protrusion of the tilt restriction body comes into contact with the inner surface of the joint ring. This contact on the inner and outer sides in the pipe diameter direction reliably maintains the bending state between the insertion port and the pipe support part on one end of the joint ring within an appropriate range in the detached state, and suppresses fluid leakage due to localized deterioration of the sealing property in the circumferential direction of the seal part.

[0018] A fourth characteristic feature of the present invention is that the tilt restriction protrusion is configured so that a contact position with the inner surface of the joint ring can be changed in the pipe radial direction.

[0019] According to the above configuration, when the tilt regulating body of the split structure of the tilt regulating part is fitted to the insertion port, there are some sites where the socket and the insertion port are bent at the fitting connection part. Even in this case, the abutment position of the tilt regulating protrusion can be changed in the pipe diameter direction according to the measured distance between the protrusion formation part of the tilt regulating body and the protrusion abutment part on the inner peripheral surface of the joint ring. This makes it possible to efficiently and reliably perform the exterior assembly work of the tilt regulating part to the insertion port even in a site where the socket and the insertion port are bent at the fitting connection part. Moreover, when a bending force due to an earthquake or uneven force due to fluid pressure is applied in the detached state, the tilt regulating protrusion of the tilt regulating body can be accurately abutted against the inner surface of the joint ring.

[0020] A fifth characteristic configuration of the present invention is that the fitting connection portion comprises a sealing material attached between the outer peripheral surface of the insertion port and the tapered inner peripheral surface of the receiving port, a pressure ring attached to the insertion port so as to be freely movable and having a pressing portion capable of pressing the sealing material from the tube axis direction, and a fastener that tightens and fixes the receiving port and the pressure ring from the tube axis direction, and the fixed connection portion of the tilt regulating portion is composed of the fastener of the fitting connection portion.

[0021] According to the above-mentioned configuration, when the socket and the pressure ring are fastened in the axial direction by the fastener, the seal material attached between the outer peripheral surface of the insertion hole and the tapered inner peripheral surface of the socket is compressed into a sealed state by the pressing part of the pressure ring. Using the fastener for the pressure ring to seal the fitting connection part, the fixed connection part of the tilt restriction part can be securely and firmly fixed to the socket.

[0022] A sixth characteristic configuration of the present invention is that the fitting connection portion is configured by mounting a seal member that opens radially inward on the inner surface of the receiving port and is compressed watertightly between the outer peripheral surface of the insertion port fitted and connected to the receiving port in a seal retaining groove that opens radially inward, and the fixed connection portion of the tilt regulating portion is configured by an engaging protrusion provided on the tilt regulating body in a state that can engage with an annular protrusion formed on the end of the outer peripheral surface of the receiving port from the outside in the pipe diameter direction, and a fastener that tightens and fixes the split tilt regulating members of the tilt regulating body to each other in a clamped state to the insertion port with the engaging protrusion of the tilt regulating body engaged with the annular protrusion of the receiving port.

[0023] According to the above configuration, when the socket and the insertion port are fitted together, the seal member attached to the seal retaining groove on the inner peripheral surface of the socket is compressed to a sealed state on the outer peripheral surface of the insertion port. The annular protrusion formed on the end of the outer peripheral surface of the socket that constitutes this fitting connection part is used to engage the engagement protrusion provided on the tilt restrictor with the annular protrusion of the socket from the outside in the pipe diameter direction. In this engaged state, the split tilt restrictor members of the tilt restrictor are fastened together with a fastener, thereby reliably and firmly fixing and connecting the fixed connection part of the tilt restrictor to the socket. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a perspective view showing a first embodiment of a structure for preventing separation of a pipe connection portion; [Diagram 2] Overall cross-sectional view when assembled [Diagram 3] Overall cross-sectional view when removed [Figure 4] Overall cross-sectional view showing the bending restriction operation in the detached state [Diagram 5] Inside view of the split collar case [Figure 6] FIG. 1 is a front view of a tilt restriction portion according to a first embodiment; [Figure 7] FIG. 11 is a front view of a main part showing another connecting structure of the tilt regulating portion of the first embodiment; [Figure 8] 11 is a front view of the tilt restriction portion of the second embodiment; [Figure 9] FIG. 11 is an overall cross-sectional view showing a second embodiment of a structure for preventing separation of a pipe connection portion when assembled; [Figure 10] Overall longitudinal section view at the time of removal [Figure 11] FIG. 11 is an overall cross-sectional view showing a third embodiment of a structure for preventing separation of a pipe connection portion when assembled; [Figure 12] Overall cross-sectional view when removed [Figure 13] 13 is a front view of the tilt restriction portion of the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] An embodiment of the present invention will be described with reference to the drawings. [First embodiment] 1 to 4 show a separation prevention structure for a pipe connection part used in a fluid transport piping system. In this separation prevention structure for a pipe connection part, an insertion port 1A of a fluid pipe 1, which is an example of one pipe part, and a receiving port 2A of a fluid pipe 2, which is an example of the other pipe part, are connected by a fitting connection part 20. A collar 30 having a split structure that surrounds the fitting connection part 20 in a sealed state is fitted over both fluid pipes 1, 2. At the portion facing the connector ring 30 and the receiving port 2A of the other fluid pipe 2 in the pipe axial direction, a first removal prevention portion 4 is provided which allows relative removal movement up to a removed state in which the receiving port 2A and the insertion port 1A are disconnected, as shown in Figures 2 and 3, and which abuts and prevents relative removal movement between the receiving port 2A and the connector ring 30 beyond a certain level in the removed state. 2 and 3, the insertion port 1A of one of the fluid pipes 1 is provided with a second removal prevention part 5 having a divided structure. The second removal prevention part 5 includes a connecting part 52 fixedly connected to the pipe support part 30d on one end side of the joint ring 30 in the pipe axial direction, and a removal prevention part 55 that increases the removal prevention resistance between the insertion port 1A and the outer circumferential surface 1a thereof as the insertion port 1A moves away from the pipe support part 30d on one end side of the joint ring 30. A tilt restriction portion 9 is provided within the joint ring 30 to restrict tilting of the insertion port 1A relative to the pipe support portion 30d on one end side of the joint ring 30 in a detached state in which the socket 2A and the insertion port 1A are disconnected.

[0026] In the above-mentioned structure for preventing separation of a pipe connection, the fluid pipes 1 and 2 are given as examples of pipe parts, but various types of pipe parts have been available in the past. For example, although not shown, examples include a branch pipe part of a split T-shaped pipe with a divided structure that is fixed to the exterior of the fluid pipe in a sealed state, a branch pipe part that is integrally formed and protrudes from the fluid pipe, and a pipe part that constitutes a part of a fluid equipment. Furthermore, the fluid pipes 1 and 2 in this embodiment are ductile cast iron pipes that constitute water pipes for transporting drinking water, which is an example of a fluid, but other cast iron pipes or steel pipes, etc. can also be used, and fluids other than drinking water can also include industrial water and gas, etc.

[0027] As shown in Figs. 1 to 3, the fitting connection 20 between the insertion port 1A of one fluid pipe 1 and the socket 2A of the other fluid pipe 2 is composed of a K-shaped mechanical joint. In this K-shaped mechanical joint, a first seal member 21 such as a rubber ring is attached between the outer peripheral surface 1a of the insertion port 1A and the tapered inner peripheral surface 2a of the socket 2A. A pressing ring 22 having a pressing portion 22a capable of pressing the first seal member 21 from the pipe axial direction is fitted to the insertion port 1A. The flange portion 22b of the pressing ring 22 and the flange portion 2b of the socket 2A are fastened and connected from the pipe axial direction by first fasteners 25 such as a plurality of metal T-head bolts 23 and nuts 24 arranged at predetermined intervals in the pipe circumferential direction. Due to the fastening connection by this first fastener 25, the first seal member 21 is compressed into a sealed state (watertight state) by the pressing portion 22a of the pressing ring 22 which is drawn and fixed to the flange portion 2b of the receiving port 2A, and this sealed state is maintained.

[0028] 1 to 5, the collar 30 is made up of split collar cases 30A and 30B made of cast iron and having a two-part structure that can be freely fitted around both fluid pipes 1 and 2 while surrounding the fitting connection parts 20 of both fluid pipes 1 and 2. The split collar cases 30A and 30B are formed to have the same shape as shown in Figs. 2 and 5. The main components of the joint ring 30 are a cylindrical peripheral wall 30a with a diameter larger than that of the socket 2A, annular side walls 30b, 30c extending from both ends of the peripheral wall 30a in the axial direction of the pipe inwardly in the radial direction, and cylindrical pipe support parts 30d, 30e extending from the inner diameter ends of the side walls 30b, 30c in the axial direction of the pipe outwardly in the axial direction of the pipe. The side wall 30b at one end, which is the side of the socket 1A, is a vertical side wall perpendicular or substantially perpendicular to the pipe axis. The side wall 30c at the other end, which is the side of the socket 2A, is a tapered side wall with a smaller diameter toward the pipe support part 30e, which is connected to the side wall 30b.

[0029] As shown in Figures 1 and 5, a connecting flange portion 30C that protrudes horizontally outward is integrally formed at both circumferential ends of the two split collar cases 30A and 30B of the collar 30. The connecting flange portions 30C of the two split collar cases 30A and 30B are fixedly connected in a sealed (watertight) state by tightening second fasteners 34 such as bolts 31 and nuts 32. As shown in Figure 2, the two split collar cases 30A and 30B are provided with a seal portion 35 (see Figure 2) that seals an enclosed space 33 formed between an inner peripheral surface 30f (see Figure 2) of the collar 30 and outer peripheral surfaces 1a and 2c of the two fluid pipes 1 and 2 including the fitting connection portion 20 from the outside.

[0030] As shown in Figures 2 and 3, the seal portion 35 is configured by fitting a second seal member 37 such as an annular gasket into an annular seal retaining groove 36 formed in each of the two split joint ring cases 30A, 30B. As shown in Figure 5, the seal retaining groove 36 comprises a first circumferential groove portion 36a extending along the pipe circumferential direction formed on the inner surface of the pipe support portion 30d facing the semi-outer peripheral surface of the insertion port 1A, two second circumferential groove portions 36b extending along the pipe circumferential direction formed at a distance from each other in the pipe axial direction on the inner surface of the pipe support portion 30e facing the semi-outer peripheral surface of the receiving port 2A, and a pipe axial direction groove portion 36c formed along the dividing surfaces of both connecting flange portions 30C in a state communicating with the circumferential ends of the first and second circumferential groove portions 36a, 36b. As shown in Figures 2 and 3, the second seal member 37 is formed by integrally molding a first circumferential seal portion 37a that is attached to the first circumferential groove portion 36a, a second circumferential seal portion 37b that is attached to the two second circumferential groove portions 36b, and a pipe axis direction seal portion (not shown) that is attached to the pipe axis direction groove portion 36c. The pipe axial direction seal portions of both second seal members 37 contact each other in a sealed (watertight) state from the pipe radial direction between the divided surfaces of both connecting flange portions 30C. The first circumferential seal portion 37a and the second circumferential seal portion 37b of both second seal members 37 contact the outer circumferential surfaces 1a, 2c of both fluid pipes 1, 2 in a sealed state along the pipe circumferential direction at both pipe support portions 30d, 30e of the collar 30.

[0031] 2 and 5, the first separation prevention portion 4 is formed integrally with a semicircular ring-shaped separation prevention wall portion 41 that protrudes inward in the pipe diameter direction to a position where it can abut against the heads 23A of the multiple T-head bolts 23 of the first fastener 25 from the pipe axial direction on the inner circumferential surface 30f between the two pipe support portions 30d, 30e of the two split joint ring cases 30A, 30B and is offset toward the other end in the pipe axial direction. In this embodiment, the separation prevention wall portion 41 is formed at the boundary portion between the peripheral wall portion 30a and the tapered side wall portion 30c on the inner circumferential surface 30f of the two split joint ring cases 30A, 30B. Of the two side surfaces of the separation prevention wall portion 41, the side surface facing the heads 23A of the multiple T-head bolts 23 in the pipe axial direction is configured as an abutment surface 41a that abuts against the heads 23A of the T-head bolts 23 and prevents relative separation movement between the receiving port 2A and the bushing 30 beyond a certain level in the separated state. A plurality of metal T-head bolts 23 arranged at predetermined intervals around the circumference of the pipe are configured as a contact member 45 fixed to the socket 2A side, and the contact surface 23a, which is the flat top surface of the head 23A of each T-head bolt 23, is configured as the contact surface 45a of the contact member 45. The contact surface 41a of the separation prevention wall portion 41 and the contact surface 23a of the head 23A of each T-head bolt 23 form a contact surface 45a of the contact member 45, each of which is formed on an orthogonal surface perpendicular to the pipe axis.

[0032] When a separation force due to an earthquake, permanent subsidence, or the like acts on the fitting connection 20 between the insertion port 1A of one fluid pipe 1 and the socket 2A of the other fluid pipe 2, as shown in Fig. 3, the abutment surface 41a of the separation prevention wall portion 41 in the joint ring 30 and the abutment surface 45a of the abutment member 45 composed of the abutment surface 23a of the head 23A of each T-head bolt 23 fixed to the socket 2A side come into face-to-face contact from the pipe axis direction, preventing further separation movement between the socket 2A of the fluid pipe 2 and the joint ring 30. At this time, the abutment surface 41a of the separation prevention wall portion 41 in the joint ring 30 and the abutment surface 45a of the abutment member 45 are formed on an orthogonal plane perpendicular to the pipe axis, so that the abutment surface 41a of the separation prevention wall portion 41 and the abutment surface 45a of the abutment member 45 come into face-to-face contact along the orthogonal direction. This ensures that the separation force can be received and improves the separation prevention effect. Furthermore, since no pushing force is generated at the split joint between the two split collar cases 30A, 30B of the collar 30 when they come into contact, a decrease in sealing performance at the split joint between the two split collar cases 30A, 30B can be suppressed.

[0033] In this embodiment, the initial assembly state is when the tip of the T-head bolt 23 of the fitting connection part 20 abuts against the inner surface of the side wall part 30b on one end side of the joint ring 30, as shown in Fig. 2. The maximum separation movement state is when the abutment surface 23a of the head part 23A of the T-head bolt 23 abuts against the abutment surface 41a of the separation prevention wall part 41 in the joint ring 30, as shown in Fig. 3. As a result, as shown in Figure 2, the distance from the abutment surface 23a of the head 23A of the T-head bolt 23 to the abutment surface 41a of the separation prevention wall portion 41 in the initial assembly state becomes the maximum separation movement distance L, and in the maximum separation movement state, as shown in Figure 3, the connection between the insertion port 1A of one fluid pipe 1 and the receiving port 2A of the other fluid pipe 2 is released, resulting in a separation state.

[0034] 1 and 2, the second separation prevention portion 5 is composed of an earthquake-resistant reinforcing metal fitting 50 with a split structure. This earthquake-resistant reinforcing metal fitting 50 is provided with a pair of metallic split clamping members 51 that are split into two in the pipe circumferential direction and are detachably clamped and fixed to the insertion port 1A of one of the fluid pipes 1 from the pipe diameter direction. The pair of split clamping members 51 are firmly clamped and fixed to the insertion port 1A of the fluid pipe 1 by fastening and connecting flange portions 51A provided at both ends in the pipe circumferential direction with third fasteners 47 such as bolts 48 and nuts 49.

[0035] The connecting portion 52 of the earthquake-resistant reinforcement fitting 50 includes an annular engaging projection 53 formed on the outer circumferential surface of the pipe support portion 30d on one end side of the joint ring 30, and an engaging recess 54 which is detachably engaged with the engaging projection 53 from the outer side in the pipe diameter direction. Of these, the engaging recess 54 is formed to open inward in the pipe diameter direction at a portion which protrudes integrally from the pipe circumferential middle portion of each divided clamping member 51 along the pipe axial center direction. When attaching the earthquake-resistant reinforcement bracket 50 to the insertion port 1A of the fluid pipe 1, as shown in Figures 1 and 2, the engagement recesses 54 formed integrally with both split clamping members 51 are engaged with the engagement protrusions 53 of the pipe support portion 30d on one end side of the joint ring 30 from the outer side in the pipe diameter direction, and in this state the flange portions 51A of both split clamping members 51 are tightened and connected to each other with the bolts 48 and nuts 49 of the third fasteners 47.

[0036] 1, gap-regulating bolts 58 that abut against the outer circumferential surface 1a of the insertion port 1A from the pipe diameter direction are screwed into multiple locations in the pipe circumferential direction of the pipe support part 30d on one end side of the joint ring 30. By screwing these multiple gap-regulating bolts 58, the annular gap between the inner circumferential surface of the pipe support part 30d on one end side and the outer circumferential surface 1a of the insertion port 1A is regulated to a constant value. When a strong separation force due to an earthquake, uneven settlement, or the like is applied, the engagement recess 54 of the earthquake-resistant reinforcement fitting 50 and the engagement protrusion 53 of the pipe support portion 30d at one end of the joint ring 30 are engaged from the pipe axis direction. When an even stronger force is applied in the separation direction in this engaged state, the pipe support portion 30d at one end of the joint ring 30 may deform toward the pipe axis direction, and the engagement recess 54 of the earthquake-resistant reinforcement fitting 50 and the engagement protrusion 53 of the joint ring 30 may come out of engagement. However, in this embodiment, the multiple gap control bolts 58 can prevent the pipe support portion 30d at one end of the joint ring 30 from deforming toward the pipe axis direction, and the engagement state between the engagement recess 54 of the earthquake-resistant reinforcement fitting 50 and the engagement protrusion 53 of the joint ring 30 can be strongly maintained.

[0037] 2 and 5, the retaining portion 55 of the earthquake-resistant reinforcing bracket 50 includes a claw housing portion 56 that is formed on the inner peripheral surface of each of the split clamping members 51 and opens radially inward, and a claw member 57 that is housed in the claw housing portion 56 and can move radially inward in the pipe direction. On the inner surface of the claw member 57, multiple rows of sharp tapered blade portions are formed along the pipe circumferential direction and capable of biting into the outer peripheral surface 1a of the insertion port 1A. The outer surface of the claw member 57 and the ceiling surface of the claw storage section 56 are formed as inclined surfaces that cause the claw member 57 to bite into and move radially inward as the claw member 57, which is stored in the claw storage section 56 while biting into the outer peripheral surface 1a of the insertion port 1A, moves away from the claw member 57 in the pipe axis direction relative to the claw storage section 56 of each split clamping member 51.

[0038] When a separation force due to an earthquake, uneven settlement, or the like acts on the fitting connection part 20 between the insertion 1A of one fluid pipe 1 and the receiving port 2A of the other fluid pipe 2, the connection between the insertion 1A of one fluid pipe 1 and the joint ring 30 is firmly maintained because the connection part 52 of the seismic reinforcement metal fitting 50 with a split structure provided at the insertion 1A is fixedly connected to the pipe support part 30d at one end of the joint ring 30. Furthermore, the claw member 57 of the retaining part 55 of the seismic reinforcement metal fitting 50 bites into the outer circumferential surface 1a of the insertion 1A as the insertion 1A moves away from the pipe support part 30d at one end of the joint ring 30, thereby increasing the retention resistance. Therefore, as a whole, the insertion 1A of one fluid pipe 1 and the pipe support part 30d at one end of the joint ring 30 are firmly fixedly connected together via the seismic reinforcement metal fitting 50. As a result, even if the insertion port 1A and the receiving port 2A separate, as shown in Figure 3, it is possible to firmly prevent the receiving port 2A from moving out of the pipe support portion 30e on the other end side of the joint ring 30, and the insertion port 1A from moving out of the pipe support portion 30d on one end side of the joint ring 30. Furthermore, the pipe support portion 30d on one end side of the collar 30 and the anti-pullout portion 55 of the earthquake-resistant reinforcement bracket 50 support two points spaced apart in the pipe axial direction of the insertion port 1A of the fluid pipe 1, so that when the insertion port 1A and the receiving port 2A are disconnected from each other as shown in Figure 3, bending of the insertion port 1A and the pipe support portion 30d on one end side of the collar 30 can be suppressed.

[0039] 2 and 3, the tilt regulating part 9 includes a tilt regulating body 90 that is fitted to the exterior of the insertion port 1A when the insertion port 1A of one fluid pipe 1 and the receiving port 2A of the other fluid pipe 2 are fitted and connected and when they are separated, and a fixed connecting part 91 that fixedly connects the tilt regulating body 90 to the receiving port 2A. The tilt regulating body 90 includes a tilt regulating cylindrical part 90b that forms a tilt regulating surface 90a with an inner diameter slightly larger than the outer diameter of the insertion port 1A, and a connecting flange part 90c that integrally protrudes radially outward from the outer circumferential surface of the tilt regulating cylindrical part 90b. As shown in Figure 3, when the insertion port 1A and the receiving port 2A are disconnected and in a detached state, the tilt restriction surface 90a of the tilt restriction body 90 abuts against the outer surface of the end of the insertion port 1A to restrict further tilting when the insertion port 1A tilts relative to the pipe support portion 30d on one end side of the joint ring 30.

[0040] 6, the tilt restriction body 90 is divided into two in the pipe circumferential direction and is composed of a pair of semicircular metal tilt restriction members 90A, 90B that are detachably attached to the insertion port 1A in the pipe radial direction. The pair of tilt restriction members 90A, 90B are configured in a circular ring shape that follows the outer circumferential surface 1a of the insertion port 1A by fastening and connecting connecting pieces 90d provided at both ends in the pipe circumferential direction with fourth fasteners 92 such as bolts 93 and nuts 94.

[0041] 2 and 6, the connecting flanges 90c of both split tilt-restricting members 90A and 90B are provided with tilt-restricting protrusions 95 that come into contact with the inner surface of the joint ring 30 as the joint ring 30 tilts relative to the pipe support portion 30d at one end thereof in a detached state in which the joint ring 30 and the socket 2A are disconnected, thereby restricting further tilting of the joint ring 30. The tilt-restricting protrusions 95 are provided at one or more locations on each connecting flange 90c. In this embodiment, the tilt-restricting protrusions 95 are formed to protrude outward in the pipe radial direction from two locations in the circumferential direction of each connecting flange 90c.

[0042] As shown in Fig. 2, the tilt restriction cylinder parts 90b of both split tilt restriction members 90A and 90B have engagement protrusions 90e that engage with the tapered gap formed between the tapered inner peripheral surface 22c of the pressure ring 22 and the outer peripheral surface 1a of the insertion port 1A from the tube axis direction. As shown in Fig. 3, the engagement protrusions 90e of both split tilt restriction members 90A and 90B maintain engagement with the tapered inner peripheral surface 22c of the pressure ring 22 even in a detached state in which the insertion port 1A and the receiving port 2A are disconnected. The engagement of the engagement protrusions 90e of both split tilt restriction members 90A and 90B with the tapered inner peripheral surface 22c of the pressure ring 22 in this detached state restricts the tilt of the insertion port 1A relative to the tube support part 30d on one end side of the joint ring 30.

[0043] As shown in Fig. 2 and Fig. 6, the fixed connection part 91 of the tilt restricting part 9 is composed of the first fastener 25 of the fitting connection part 20. Specifically, bolt insertion holes 91a through which the tips of the T-head bolts 23 can be inserted are formed in the connecting flange parts 90c of both split tilt restricting members 90A and 90B at the locations corresponding to the T-head bolts 23 of the first fastener 25. Fixed connection nuts 91b are screwed into the tips of the T-head bolts 23 inserted into the bolt insertion holes 91a of both split tilt restricting members 90A and 90B. The fixed connection nuts 91b are tightened to fixedly connect the tilt restricting body 90 to the socket 2A.

[0044] As shown in Fig. 3, in a detached state in which the insertion port 1A and the receiving port 2A are disconnected, bending forces due to earthquakes, uneven forces due to fluid pressure, etc. may act, causing the insertion port 1A to tilt relative to the pipe support portion 30d on one end side of the joint ring 30 as shown in Fig. 4. At this time, the outer surface of the end of the insertion port 1A abuts against the tilt restriction surface 90a of the tilt restriction body 90, and a tilt restriction protrusion 95 of the tilt restriction body 90 abuts against the inner surface of the joint ring 30. This maintains the bending state between the insertion port 1A and the pipe support portion 30d on one end side of the joint ring 30 in the detached state within an appropriate range, thereby suppressing fluid leakage due to a local decrease in sealing performance in the circumferential direction of the seal portion 35.

[0045] In the first embodiment described above, the first separation prevention portion 4 is configured to prevent separation movement between the socket 2A and the joint ring 30 by the contact surface 41a of the separation prevention wall portion 41 provided in the joint ring 30 and the head 23A of each T-head bolt 23 fixed to the socket 2A side. However, this is not limited to the configuration. For example, in the case of a joint ring 30 that is not provided with the separation prevention wall portion 41, the first separation prevention portion 4 is formed, with reference to Figures 2 and 3, on the other end side in the pipe axis direction of the inner surface between both pipe support portions 30d, 30e of the joint ring 30, in other words, on the side wall portion 30c on the other end side of the joint ring 30, so as to form a thick-walled separation prevention portion 42 that can come into contact with the tapered outer peripheral surface portion 2e on the outer peripheral surface 2c of the socket 2A from the pipe axis direction. The contact surface 42a of the removal prevention portion 42 is formed in a tapered shape with the same gradient as the tapered outer peripheral surface portion 2e of the outer peripheral surface 2c of the socket 2A.

[0046] In the above-mentioned first removal prevention portion 4, when a removal force due to an earthquake, uneven settlement, or the like acts on the fitting connection portion 20 between the insertion port 1A and the socket 2A, the abutment surface 42a of the removal prevention portion 42 formed on the side wall portion 30c on the other end side of the joint ring 30 comes into contact with the tapered outer peripheral surface portion 2e on the outer peripheral surface 2c of the socket 2A, thereby preventing further removal movement of the two. At this time, since the abutment surface 42a of the removal prevention portion 42 is formed in a tapered shape with the same gradient as the tapered outer peripheral surface portion 2e on the outer peripheral surface 2c of the socket 2A, the abutment surface 42a of the removal prevention portion 42 comes into contact with the tapered outer peripheral surface portion 2e of the socket 2A in a face-to-face contact state, and removal movement of the socket 2A and the joint ring 30 can be strongly prevented. Moreover, when the abutment surface 42a of the separation prevention portion 42 abuts against the tapered outer peripheral surface portion 2e of the receiving port 2A, a force is generated that pushes open the divided surfaces of the split-structured joint ring 30. However, in the present invention, the abutment surface 42a of the separation prevention portion 42 is formed on the other end side in the pipe axial direction between both pipe support portions 30d, 30e of the joint ring 30, so that the push-open force is reduced by the amount of deviation of the abutment surface 42a of the separation prevention portion 42 from both pipe support portions 30d, 30e, and the occurrence of fluid leakage due to a decrease in the sealing performance of the seal portion 35 accompanying the pushing open of the divided surfaces of the joint ring 30 can be suppressed.

[0047] [Another Connection Structure of the Tilt Restriction Body 90 of the First Embodiment] In the first embodiment described above, as shown in FIG. 6, as a first example of the tilt restricting body 90, the connecting pieces 90d provided at both ends in the pipe circumferential direction of the split tilt restricting members 90A and 90B are connected to each other by a fourth fastener 92 such as a bolt 93 and a nut 94. Instead of this connecting structure of the tilt restricting body 90, another connecting structure shown in FIG. 7 may be adopted. In this other connecting structure, a second connecting piece 90f that can be arranged to overlap from the pipe radial direction is integrally formed at each of both ends in the pipe circumferential direction of the split tilt restricting members 90A and 90B. A second bolt insertion hole 91c through which the tip of the T-head bolt 23 can be inserted is formed in each set of the second connecting pieces 90f that are arranged to overlap. As a result, the split tilt restricting members 90A and 90B can be connected in an annular shape using the T-head bolt 23 and the fixed connecting nut 91b that constitute the fixed connecting portion 91 of the tilt restricting portion 9.

[0048] [Second embodiment of tilt restriction body 90] In the second embodiment of the tilt restricting body 90 shown in Fig. 8, the tilt restricting protrusion 95 is configured so that the contact position with the inner surface of the joint ring 30 can be changed in the pipe diameter direction. Specifically, the tilt restricting protrusion 95 includes female threads 95A formed at two circumferential positions of each of the split tilt restricting members 90A and 90B, a tilt restricting bolt 95B screwed into the female threads 95A from the pipe diameter direction, and a lock nut 95C for fixing the tilt restricting bolt 95B whose contact position in the pipe diameter direction has been adjusted. The contact position with the inner surface of the joint ring 30 can be changed in the pipe diameter direction by screwing the tilt restricting bolt 95B.

[0049] When the tilt regulating body 90 of the split structure of the tilt regulating part 9 is fitted to the insertion port 1A, there are some sites where the socket 2A and the insertion port 1A are bent at the fitting connection part 20. Even in this case, the abutment position of the tilt regulating bolt 95B can be changed in the pipe diameter direction according to the measured distance between the tip of the tilt regulating bolt 95B of the tilt regulating body 90 and the protruding abutment part on the inner peripheral surface 30f of the joint ring 30. This makes it possible to efficiently and reliably perform the exterior assembly work of the tilt regulating part 9 to the insertion port 1A even in a site where the socket 2A and the insertion port 1A are bent at the fitting connection part 20. Moreover, when a bending force due to an earthquake or uneven force due to fluid pressure acts in the detached state, the tilt regulating bolt 95B of the tilt regulating body 90 can be accurately abutted against the inner surface of the joint ring 30.

[0050] Second Embodiment In the second embodiment of the structure for preventing separation of a pipe connection portion shown in Figs. 9 and 10, the tilt restriction protrusion 95 of the tilt restriction body 90 described in the first embodiment is omitted. Therefore, as shown in Fig. 10, in a separated state in which the connection between the insertion port 1A and the socket 2A is released, a bending force due to an earthquake or uneven force due to fluid pressure acts, causing the insertion port 1A to tilt relative to the pipe support portion 30d on one end side of the joint ring 30. At this time, the outer surface of the end of the insertion port 1A abuts against the tilt restriction surface 90a of the tilt restriction body 90. As a result, the bending state between the insertion port 1A and the pipe support portion 30d on one end side of the joint ring 30 in the separated state can be maintained within an appropriate range, and leakage of fluid due to a local decrease in sealing ability in the circumferential direction of the seal portion 35 can be suppressed. The other configurations are the same as those described in the first embodiment, so the same components are denoted by the same reference numbers as in the first embodiment and the description thereof will be omitted.

[0051] Third Embodiment 11 to 13, a fitting connection 20 between an insertion port 1A of one fluid pipe 1 and a socket 2A of the other fluid pipe 2 is configured with a T-shaped mechanical joint. This T-shaped mechanical joint is configured by fitting a third seal member 61 such as a rubber ring that is compressed into a sealed state (watertight state) between the outer peripheral surface 1a of the insertion port 1A that is fitted and connected to the socket 2A and the outer peripheral surface 1a of the insertion port 1A.

[0052] A split-structured joint ring 30 that surrounds the mating connection portion 20 in a sealed state includes a tilt control portion 9 that controls the tilting of the insertion port 1A relative to the pipe support portion 30d on one end side of the joint ring 30 when the receiving port 2A and the insertion port 1A are in a disconnected state where they are disconnected. As shown in Fig. 11 and Fig. 12, the tilt regulating part 9 includes a tilt regulating body 90 that is fitted to the exterior of the insertion port 1A when the insertion port 1A of one fluid pipe 1 and the socket 2A of the other fluid pipe 2 are in a mated and connected state and when they are separated, and a fixed connecting part 91 that fixedly connects the tilt regulating body 90 to the socket 2A. The tilt regulating body 90 has a tilt regulating surface 90a with an inner diameter slightly larger than the outer diameter of the insertion port 1A. As shown in Fig. 12, when the insertion port 1A and the socket 2A are in a disconnected state where they are disconnected, the tilt regulating surface 90a abuts against the outer surface of the end of the insertion port 1A when the insertion port 1A tilts relative to the pipe support part 30d on one end side of the collar 30, thereby restricting further tilting.

[0053] 13, the tilt restriction body 90 is divided into two in the pipe circumferential direction and includes a pair of semicircular metal second divided tilt restriction members 90C, 90D that are fitted to the insertion port 1A in a detachable manner from the pipe diameter direction. The pair of second divided tilt restriction members 90C, 90D are configured in a circular ring shape that follows the outer circumferential surface 1a of the insertion port 1A by fastening and connecting third connecting pieces 90g provided at both ends in the pipe circumferential direction with fourth fasteners 92 such as T-head bolts 93A and nuts 94.

[0054] As shown in Fig. 11 and Fig. 13, in a detached state in which the insertion port 1A and the socket 2A are disconnected, both second split tilt-restricting members 90C and 90D are provided with a tilt-restricting protrusion 95 that abuts against the inner surface of the joint ring 30 as the insertion port 1A tilts relative to the pipe support portion 30d at one end of the joint ring 30 to restrict further tilt of the insertion port 1A. The tilt-restricting protrusion 95 is provided at one or more locations on each of the split tilt-restricting members 90A and 90B. In this embodiment, the tilt-restricting protrusion 95 is formed to protrude outward along the pipe diameter direction from two locations in the circumferential direction of each of the split tilt-restricting members 90A and 90B.

[0055] The tilt restriction protrusion 95 is configured so that the contact position with the inner surface of the joint ring 30 can be changed in the pipe diameter direction. Specifically, the tilt restriction protrusion 95 includes female threaded portions 95A formed at two circumferential positions of each of the split tilt restriction members 90A and 90B, a tilt restriction bolt 95B screwed into the female threaded portion 95A from the pipe diameter direction, and a lock nut 95C for fixing the tilt restriction bolt 95B whose contact position in the pipe diameter direction has been adjusted. The contact position with the inner surface of the joint ring 30 is changed in the pipe diameter direction by screwing the tilt restriction bolt 95B.

[0056] The fixed connecting portion 91 is composed of a second engaging protrusion 91d provided on the tilting control body 90 in a state in which it can be engaged and disengaged from the outside in the pipe diameter direction with respect to the annular protrusion 2g formed at the end of the outer circumferential surface 2c of the receiving port 2A, and a fourth fastener 92 that clamps and fixes the third connecting pieces 90g of the second split tilting control members 90C, 90D to the insertion port 1A in a state in which they are clamped together with the second engaging protrusion 91d of the tilting control body 90 engaged with the annular protrusion 2g of the receiving port 2A.

[0057] At the portion facing the collar 30 and the receiving port 2A side of the other fluid pipe 2 in the pipe axial direction, as shown in Figures 11 and 12, a first removal prevention portion 4 is provided which allows relative removal movement up to a removed state in which the receiving port 2A and the insertion port 1A are disconnected, and which abuts and prevents relative removal movement between the receiving port 2A and the collar 30 beyond a certain level in the removed state. As shown in Figures 11 and 12, the first separation prevention portion 4 is formed integrally with a semicircular ring-shaped separation prevention wall portion 41 that protrudes inward in the pipe diameter direction to a position where it can abut against the abutment portion 90h formed on the other end side of both second divided tilting restriction members 90C and 90D from the pipe axis direction on the inner peripheral surface 30f between both pipe support portions 30d and 30e of both split joint ring cases 30A and 30B at a portion offset toward the other end side in the pipe axis direction. In this embodiment, the separation prevention wall portion 41 is formed at the boundary portion between the peripheral wall portion 30a and the tapered side wall portion 30c on the inner peripheral surface 30f of both split joint ring cases 30A and 30B. Of the two side surfaces of the separation prevention wall portion 41, the side surface facing the abutment portions 90h of both second split tilting regulating members 90C, 90D in the pipe axial direction is configured as an abutment surface 41a that abuts against the abutment portions 90h of both second split tilting regulating members 90C, 90D and prevents relative separation movement between the receiving port 2A and the bushing 30 beyond a certain level in the separated state. The other configurations are the same as those described in the first embodiment, so the same components are denoted by the same reference numbers as in the first embodiment and the description thereof will be omitted.

[0058] Other embodiments (1) In the first embodiment described above, the tilt restricting body 90 is provided with a tilt restricting surface 90a that restricts the tilting of the insertion port 1A by contacting the outer surface of the insertion port 1A that tilts relative to the pipe support portion 30d at one end of the joint ring 30, and a tilt restricting protrusion 95 that restricts further tilting of the insertion port 1A by contacting the inner surface of the joint ring 30 as the insertion port 1A tilts relative to the pipe support portion 30d at one end of the joint ring 30. However, the present invention is not limited to this configuration, and for example, the present invention may be implemented with only one of the tilt restricting surfaces 90a or the tilt restricting protrusion 95.

[0059] (2) In the second embodiment of the tilt restriction body 90 described above, the contact position with the inner surface of the joint ring 30 is changed in the pipe diameter direction by screwing the tilt restriction bolt 95B. However, this is not limited to the above configuration, and for example, a plurality of tilt restriction protrusions 95 having different lengths in the pipe diameter direction may be selectively attached to the tilt restriction body 90 so that the contact position with the inner surface of the joint ring 30 can be changed in the pipe diameter direction by replacing the tilt restriction protrusions 95.

[0060] (3) In the first embodiment described above, the second removal prevention portion 5 is configured as the earthquake-resistant reinforcing bracket 50 having a separate structure from the collar 30, but the second removal prevention portion 5 may be configured by being assembled to the collar 30. In this case, the pipe support portion 30d on one end side in the pipe axial direction of the collar 30 is provided with a removal prevention portion 55 that increases the removal prevention resistance between the pipe support portion 30d on one end side of the collar 30 and the outer circumferential surface of the insertion port 1A as the insertion port 1A moves away from the pipe support portion 30d on one end side of the collar 30. [Explanation of symbols]

[0061] 1 Pipe section (fluid pipe) 1A socket 1a Outer surface 2 Second disengagement prevention part 2A socket 2a Inner surface 2c Outer surface 2e Tapered outer peripheral part 2g Ring protrusion 4 1st disengagement prevention part 5 Second disengagement prevention part 9 Tilt control section 20 Mating connection 21 sealing member (first sealing portion) 22 Push Ring 22a Pressing part 25 Fastener (First Fastener) 30 Splice Ring 30d tube support 60 Seal retaining groove 61 sealing member (third sealing member) 90 Tilt control body 90A Split tilt control member 90B Divided tilt control member 90C Second divided tilt restriction member 90D Second divided tilt restriction member 90a Tilt control surface 91 Fixed connection part 91d Engagement protrusion (second engagement protrusion) 92 Fastener (4th fastener) 95 Tilt control protrusion

Claims

[Claim 1] a split-structured collar that hermetically surrounds the fitting connection between the insertion port of one pipe section and the receiving port of the other pipe section is fitted over both pipe sections, and a first removal prevention portion that abuts and prevents the receiving port and the collar from moving apart relative to each other beyond a certain level is provided at a portion that faces the insertion port and the receiving port side of the collar in the pipe axial direction, and a second removal prevention portion that has a removal prevention portion that increases in resistance to removal between the insertion port and the outer peripheral surface of the insertion port as the insertion port moves apart is provided at a pipe support portion side at one end of the collar in the pipe axial direction, the first separation prevention portion is an inner peripheral surface between the pipe support portion on one end side and the pipe support portion on the other end side of the joint ring, and is configured with an abutment surface at a portion offset toward the other end side in the pipe axis direction, the abutment surface abutting against the abutted portion on the receiving port side from the pipe axis direction to prevent relative separation movement between the receiving port and the joint ring beyond a certain level, The first separation prevention portion is a separation prevention structure for a pipe connection portion in which, when the insertion port is tilted relative to the pipe support portion on one end side of the connecting ring, the abutted portion and the abutment surface are separated in the pipe axial direction at the tilting side, and the abutted portion and the abutment surface abut at the side opposite the tilting side.

Images