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 split-structured flange that hermetically surrounds the mating connection 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] Patent Document 1 discloses a pipe mounting structure as an example of a structure for preventing separation of the above-mentioned pipe connection. In this pipe mounting structure, the fitting connection between the insertion port of one pipe section and the socket port of the other pipe section is made up of a K-shaped mechanical joint. In this mechanical joint, a sealing material such as a rubber ring is fitted between the outer peripheral surface of the insertion port and the tapered inner peripheral surface of the socket port. This sealing material is secured by bolts between the flange part of the press ring, which has a pressing part that can press from the axial direction of the pipe, and the flange part of the socket port. The connection is tightened with a nut. This tightening connection causes the pressure part of the pressure ring, which is pulled and fixed to the flange part of the receiving port, to compress the seal material into a watertight state, and this watertight state is maintained.

[0003] In addition, the split-structured flange that surrounds the mechanical joint, which is the mating connection, in a sealed state has as its main components a cylindrical peripheral wall portion that is larger in diameter than the receiving port, annular side wall portions that extend integrally radially inward from both ends of the peripheral wall portion in the pipe axis direction, and pipe support portions that extend integrally outward along the pipe axis 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 outer peripheral surfaces of both pipe parts.

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

[0005] In addition, a separation prevention section with a split structure 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 section is formed to be larger than the inner diameter of the pipe support section on one end side of the joint ring that is on the insertion port side, so that when the insertion port and the receiving port are separated, the separation prevention section clamped and fixed to the insertion port abuts against the pipe support section on one end side of the joint ring from the direction of the pipe axis, preventing further separation movement. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-138637 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, which can lead to fluid leakage from the area where the sealing ability is reduced.

[0008] In view of this situation, the main object of the present invention is to provide a structure for preventing separation of a pipe connection part, which can reliably prevent the insertion port and receiving port from moving away from the collar while improving the absorption capacity against separation forces, and which can maintain the bending state between the insertion port and the pipe support part on one end of the collar within an appropriate range, thereby suppressing fluid leakage caused by localized deterioration of the sealing ability around the seal part. [Means for solving the problem]

[0009] The first characteristic configuration of the present invention is that a split-structured collar that surrounds the mating connection between the insertion port of one pipe section and the receiving port of the other pipe section in a sealed state is fitted over both pipe sections, and at the portion facing the collar and the receiving port side of the other pipe section in the pipe axial direction, a first separation prevention portion is provided that allows relative separation movement up to a separated state in which the receiving port and the collar are disconnected, and abuts to prevent relative separation movement between the receiving port and the collar from exceeding a certain level in the separated state, and a second separation prevention portion is provided on the pipe support portion side at one end in the pipe axial direction of the collar, the second separation prevention portion having a removal prevention portion that increases the resistance to removal between the outer surface of the collar as the insertion port moves away from the pipe, and a tilt prevention portion is provided within the collar that regulates tilting of the insertion port relative to the pipe support portion at one end of the collar 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 separation prevention section provided at the location facing the axial direction of the collar and the socket side of the other pipe section allows relative separation movement until the socket and the spigot are disconnected. This makes it possible to absorb large separation forces acting on the fitting connection between the spigot and the socket. At the same time, relative separation movement between the socket and the collar beyond a certain level can be reliably prevented in the disconnected state, so the socket will not come loose from the pipe support section on the other end of the collar.

[0011] In addition, the anti-detachment portion of the second anti-detachment portion provided on the pipe support portion side at one end of the collar in the pipe axial direction increases in anti-detachment resistance between the outer surface of the insertion port as the insertion port moves away from the pipe support portion at one end of the collar, so that overall, the insertion port of one pipe portion and the pipe support portion at one end of the collar are firmly fixed and connected together via the second anti-detachment portion. This means that even if the insertion port and the receiving port separate, the receiving port can be firmly prevented from moving out of the pipe support portion on the other end of the collar, and the insertion port can be firmly prevented from moving out of the pipe support portion on one end of the collar.

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

[0013] Therefore, the relative movement of the spigot and spigot until they are disconnected improves the ability to absorb the separation force acting on the mating connection. And yet, once the spigot and spigot have moved to the disconnected state, the first and second separation prevention sections cooperate to reliably prevent further movement, preventing fluid leakage. Furthermore, the bending state between the spigot and the pipe support section on one end of the collar in the disconnected state is maintained within an appropriate range, preventing fluid leakage due to localized deterioration in the sealing performance around the circumferential direction of the seal section.

[0014] The second characteristic configuration of the present invention is that the tilting control section is provided with a tilting control 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 tilting control surface that can abut against the outer surface of the insertion port that tilts in the separated state, and a fixed connecting section that fixedly connects the tilting control body to the receiving port.

[0015] According to the above configuration, when the socket and the spigot are mated and connected, the tilt restrictor of the split structure of the tilt restrictor is fitted over the socket and fixedly connected to the socket by the fixed connecting part. Even when the socket and the spigot move relative to each other to a separated state due to an earthquake, uneven settlement, or the like, the tilt restrictor remains attached to the spigot. Therefore, when a bending force due to an earthquake or uneven force caused by fluid pressure acts in the separated state, the tilt restricting surface of the tilt restrictor fixedly connected to the socket abuts against the outer surface of the spigot. This reliably maintains 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, preventing fluid leakage due to localized loss of sealing in the circumferential direction of the seal portion.

[0016] A third characteristic feature of the present invention is that the tilting restriction body is provided with a tilting restriction protrusion that abuts against the inner surface of the collar as the insertion port tilts in the detached state.

[0017] According to the above configuration, when bending force due to earthquake or uneven force due to fluid pressure is applied in the detached state, the tilt restricting surface of the tilt restricting body fixedly connected to the socket abuts against the outer surface of the spigot, and the tilt restricting protrusion of the tilt restricting body abuts against the inner surface of the collar. This abutment on the inner and outer sides in the pipe diameter direction reliably maintains the bending state between the spigot and the pipe support part on one end of the collar within an appropriate range in the detached state, and suppresses fluid leakage due to localized deterioration of the sealing seal in the circumferential direction.

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

[0019] According to the above configuration, when the tilt restrictor having a split structure for the tilt restrictor is fitted to the spigot, there are cases where the socket and the spigot are bent at their mating connection. Even in such cases, the abutment position of the tilt restrictor protrusion can be changed in the pipe diameter direction based on the measured distance between the protrusion-forming portion of the tilt restrictor and the protrusion abutment portion on the inner surface of the collar. This allows for efficient and reliable fitting of the tilt restrictor to the spigot, even in cases where the socket and the spigot are bent at their mating connection. Furthermore, when a bending force is applied due to an earthquake or uneven force caused by fluid pressure in the detached state, the tilt restrictor protrusion of the tilt restrictor can be accurately abutted against the inner surface of the collar.

[0020] The 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 direction of the pipe axis, and a fastener that tightens and fixes the receiving port and the pressure ring from the direction of the pipe axis, and the fixed connection portion of the tilting control portion is composed of the fastener of the fitting connection portion.

[0021] With this configuration, when the socket and the pressure ring are fastened together in the axial direction with a fastener, the seal material attached between the outer periphery of the socket and the tapered inner periphery 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 this mating connection, the fixed connection part of the tilt restriction part can be securely and firmly fixed to the socket.

[0022] The sixth characteristic configuration of the present invention is that the fitting connection portion is configured by attaching a seal member that opens radially inward on the inner surface of the receiving port and is compressed watertightly between the outer surface of the insertion port fitted into the receiving port, and the fixed connection portion of the tilting control portion is configured by an engaging protrusion provided on the tilting control body in a state that can engage with an annular protrusion formed on the end of the outer surface of the receiving port from the outside in the pipe diameter direction, and a fastener that clamps and fixes the split tilting control members of the tilting control body to the insertion port while engaging the engaging protrusion of the tilting control body with the annular protrusion of the receiving port.

[0023] According to the above configuration, when the socket and the insertion port are mated, the seal member attached to the seal retaining groove on the inner peripheral surface of the socket is compressed to form a sealed seal against the outer peripheral surface of the insertion port. The annular protrusion formed on the end of the outer peripheral surface of the socket, which constitutes this mating connection, is used to matingly engage the engagement protrusion on the tilt restrictor with the annular protrusion on the socket from the outside in the pipe diameter direction. In this mating state, the split tilt restrictor members of the tilt restrictor are fastened together with fasteners, thereby reliably and firmly fixing the fixed connection portion of the tilt restrictor to the socket. [Brief explanation 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; [Figure 2] Overall cross section when assembled [Figure 3] Overall cross section when removed [Figure 4] Overall cross-sectional view showing the bending restriction operation in the detached state [Figure 5] Inside view of the split collar case [Figure 6] 1 is a front view of a tilting restriction portion of the first embodiment; [Figure 7] FIG. 10 is a front view of a main part showing another connecting structure of the tilting restriction portion of the first embodiment; [Figure 8] 10 is a front view of the tilt restriction portion of the second embodiment. [Figure 9] FIG. 10 is an overall cross-sectional view showing a second embodiment of the structure for preventing separation of a pipe connection portion when assembled; [Figure 10] Overall longitudinal cross section at the time of removal [Figure 11] FIG. 10 is an overall cross-sectional view showing a third embodiment of the structure for preventing separation of a pipe connection portion when assembled; [Figure 12] Overall cross section when removed [Figure 13] 10 is a front view of the tilt restriction portion of the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[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 transportation 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 socket 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 hermetically surrounds this fitting connection part 20 is fitted over both fluid pipes 1 and 2. At the portion facing the bearing ring 30 and the receiving port 2A of the other fluid pipe 2 in the pipe axial direction, as shown in Figures 2 and 3, a first separation prevention portion 4 is provided which allows relative separation movement up to a separated state in which the receiving port 2A and the insertion port 1A are disconnected, and abuts to prevent relative separation movement between the receiving port 2A and the bearing ring 30 beyond a certain level in the separated state. 2 and 3, a second separation prevention part 5 having a divided structure is provided at the insertion port 1A of one fluid pipe 1. This second separation prevention part 5 includes a connecting part 52 fixedly connected to the pipe support part 30d at one end of the collar 30 in the pipe axial direction, and a stop part 55 that increases the resistance to removal between the second separation prevention part 52 and the outer peripheral surface 1a of the insertion port 1A as the insertion port 1A moves away from the pipe support part 30d at one end of the collar 30. A tilting restriction section 9 is provided within the collar 30 to restrict tilting of the insertion port 1A relative to the pipe support section 30d at one end of the collar 30 when the socket 2A and insertion port 1A are in a disconnected state where they are disconnected.

[0026] In the above-described structure for preventing separation of a pipe connection, fluid pipes 1 and 2 are used as an example of the pipe portion, but various types of pipe portions have been used in the past. For example, although not shown, examples include a branch pipe portion 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 portion formed integrally with the fluid pipe and protruding, and a pipe portion that constitutes part of 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, steel pipes, etc. can also be used, and fluids other than drinking water include industrial water and gas.

[0027] As shown in Figures 1 to 3, the mating connection 20 between the outlet 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 outlet 1A and the tapered inner peripheral surface 2a of the socket 2A. A pressure ring 22, which has a pressing portion 22a that can press the first seal member 21 from the pipe axial direction, is attached to the exterior of the outlet 1A. The flange portion 22b of the pressure ring 22 and the flange portion 2b of the socket 2A are tightened and connected from the pipe axial direction by first fasteners 25, such as a plurality of metal T-head bolts 23 and nuts 24, which are arranged at predetermined intervals around the pipe circumferential direction. By the tightening 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 pulled and fixed to the flange portion 2b of the socket 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 over both fluid pipes 1 and 2 while surrounding the fitting connection parts 20 of both fluid pipes 1 and 2. As shown in Figs. 2 and 5, the split collar cases 30A and 30B are configured to have the same shape. The collar 30 primarily comprises a cylindrical peripheral wall 30a with a diameter larger than that of the socket 2A, annular side walls 30b and 30c extending radially inward from both ends of the peripheral wall 30a in the pipe axis direction, and cylindrical tube supports 30d and 30e extending radially outward from the inner diameter ends of each side wall 30b and 30c in the pipe axis direction. The side wall 30b at one end, which faces the socket 1A, is vertical and perpendicular to the pipe axis. The side wall 30c at the other end, which faces the socket 2A, is tapered, gradually decreasing in diameter toward the adjacent tube support 30e.

[0029] As shown in Figures 1 and 5, connecting flanges 30C that protrude horizontally outward are integrally formed at both circumferential ends of the two split collar cases 30A, 30B of the collar 30. The connecting flanges 30C of the two split collar cases 30A, 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, 30B are provided with seals 35 (see Figure 2) that seal against the outside an enclosed space 33 formed between the inner peripheral surface 30f (see Figure 2) of the collar 30 and the outer peripheral surfaces 1a, 2c of the two fluid pipes 1, 2 including the fitting connection portion 20.

[0030] As shown in Figures 2 and 3, the sealing portion 35 is configured by fitting a second sealing 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 and 30B. As shown in Figure 5, the seal retaining groove 36 comprises a first circumferential groove portion 36a extending along the pipe circumferential direction and 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 and spaced apart 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 and 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 in the pipe radial direction between the divided surfaces of both connecting flange portions 30C. The first circumferential direction seal portion 37a and the second circumferential direction seal portion 37b of both second seal members 37 contact in a sealed state with the outer peripheral surfaces 1a, 2c of both fluid pipes 1, 2 in 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 the inner circumferential surface 30f between the pipe support portions 30d, 30e of the split joint ring cases 30A, 30B at a position offset toward the other end in the pipe axial direction, and has a semicircular ring-shaped separation prevention wall portion 41 that protrudes inward in the pipe radial direction to a position where it can abut from the pipe axial direction against the heads 23A of the multiple T-head bolts 23 of the first fastener 25. In this embodiment, the separation prevention wall portion 41 is formed at the boundary between the peripheral wall portion 30a and the tapered side wall portion 30c on the inner circumferential surface 30f of the 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 socket 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 to double as abutment members 45 fixed to the socket 2A side, and the abutment surface 23a, which is the flat top surface of the head 23A of each T-head bolt 23, is configured as the abutment surface 45a of the abutment member 45. The contact surface 41a of the separation prevention wall portion 41 and the contact surface 45a of the contact member 45, which is composed of the contact surface 23a of the head 23A of each T-head bolt 23, are each formed on an orthogonal plane perpendicular to the pipe axis.

[0032] When a separation force due to an earthquake, permanent subsidence, or the like acts on the mating connection 20 between the outlet 1A of one fluid pipe 1 and the socket 2A of the other fluid pipe 2, as shown in Figure 3, the abutment surface 41a of the separation prevention wall 41 in the collar 30 and the abutment surface 45a of the abutment member 45, which is composed of the abutment surfaces 23a of the heads 23A of the T-head bolts 23 fixed to the socket 2A, come into face-to-face contact along the pipe axis, preventing further separation between the socket 2A of the fluid pipe 2 and the collar 30. Because the abutment surfaces 41a of the separation prevention wall 41 in the collar 30 and the abutment surface 45a of the abutment member 45 are formed on perpendicular planes perpendicular to the pipe axis, the abutment surfaces 41a of the separation prevention wall 41 and the abutment surface 45a of the abutment member 45 come into face-to-face contact along the perpendicular direction. This reliably withstands the separation force and improves the separation prevention effect. Furthermore, since no pushing force is generated at the split joints acting on the two split collar cases 30A, 30B of the collar 30 when they come into contact, a decrease in sealing performance at the split joints of the two split collar cases 30A, 30B can be suppressed.

[0033] In this embodiment, as shown in Fig. 2, 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. Also, as shown in Fig. 3, 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 inside the joint ring 30. 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 is 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 and the state is separated.

[0034] 1 and 2, the second separation prevention section 5 is composed of a seismic reinforcement bracket 50 with a split structure. This seismic reinforcement bracket 50 is divided into two in the pipe circumferential direction and is provided with a pair of metal split clamping members 51 that 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 tightening and connecting flange portions 51A provided on 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 peripheral surface of the pipe support portion 30d on one end side of the flange 30, and an engaging recess 54 that is releasably engaged with the engaging projection 53 from the outer side in the pipe diameter direction. The engaging recess 54 is formed to open inward in the pipe diameter direction at a portion that protrudes integrally from the pipe circumferential middle portion of each divided clamping member 51 along the pipe axis. 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 engaging recesses 54 formed integrally with both split clamping members 51 are engaged with the engaging protrusions 53 of the pipe support portion 30d on one end side of the collar 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 together with the bolts 48 and nuts 49 of the third fasteners 47.

[0036] 1, gap-restricting bolts 58 that abut against the outer peripheral surface 1a of the insertion port 1A from the pipe diameter direction are screwed into multiple locations around the pipe on the pipe support portion 30d on one end of the collar 30. By screwing these multiple gap-restricting bolts 58, the annular gap between the inner peripheral surface of the pipe support portion 30d on one end and the outer peripheral surface 1a of the insertion port 1A is restricted to a constant value. When a strong separation force is applied due to an earthquake, differential settlement, or the like, the engaging recess 54 of the earthquake-resistant reinforcement fitting 50 and the engaging protrusion 53 of the pipe support portion 30d on one end of the collar 30 engage from the pipe axis. If an even stronger force is applied in the separation direction in this engaged state, the pipe support portion 30d on one end of the collar 30 may deform toward the pipe axis, potentially causing the engagement between the engaging recess 54 of the earthquake-resistant reinforcement fitting 50 and the engaging protrusion 53 of the collar 30 to disengage. However, in this embodiment, the multiple clearance control bolts 58 can prevent the pipe support portion 30d on one end of the collar 30 from deforming toward the pipe axis, thereby firmly maintaining the engagement between the engaging recess 54 of the earthquake-resistant reinforcement fitting 50 and the engaging protrusion 53 of the collar 30.

[0037] 2 and 5, the retaining portion 55 of the earthquake-resistant reinforcing bracket 50 includes claw storage portions 56 that are formed on the inner peripheral surfaces of both split clamping members 51 and open radially inward, and claw members 57 that are housed within the claw storage portions 56 and are movable radially inward in the pipe direction. The inner surface of the claw members 57 is formed with multiple rows of sharp, tapered blades that run along the pipe circumference and are 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 storage section 56 of each split clamping member 51 in the direction of the pipe axis.

[0038] When a separation force due to an earthquake, uneven settlement, or the like acts on the fitting connection 20 between the insertion 1A of one fluid pipe 1 and the socket 2A of the other fluid pipe 2, the connection between the insertion 1A of one fluid pipe 1 and the collar 30 is firmly maintained because the connecting portion 52 of the separable earthquake-resistant reinforcement bracket 50 provided at the insertion 1A is fixedly connected to the pipe support portion 30d on one end of the collar 30. Furthermore, as the insertion 1A moves away from the pipe support portion 30d on one end of the collar 30, the claw members 57 of the retaining portion 55 of the earthquake-resistant reinforcement bracket 50 bite into the outer peripheral surface 1a of the insertion 1A, thereby increasing the retention resistance. Therefore, as a whole, the insertion 1A of one fluid pipe 1 and the pipe support portion 30d on one end of the collar 30 are firmly fixedly connected together via the earthquake-resistant reinforcement bracket 50. As a result, even if the insertion port 1A and the receiving port 2A separate, as shown in Figure 3, the insertion port 2A can be firmly prevented from moving out of the pipe support portion 30e on the other end side of the collar 30, and the insertion port 1A can be firmly prevented from moving out of the pipe support portion 30d on one end side of the collar 30. Furthermore, the pipe support portion 30d on one end 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 axis direction at the insertion port 1A of the fluid pipe 1, so that, as shown in Figure 3, when the insertion port 1A and the receiving port 2A are disconnected, bending of the insertion port 1A and the pipe support portion 30d on one end of the collar 30 can be suppressed.

[0039] 2 and 3, the tilt restricting part 9 includes a tilt restricting body 90 that is fitted onto the exterior of the outlet 1A of one fluid pipe 1 when the outlet 1A of the other fluid pipe 2 is mated and connected to the socket 2A of the other fluid pipe 2, and a fixed connecting part 91 that fixedly connects the tilt restricting body 90 to the socket 2A. The tilt restricting body 90 has a tilt restricting cylindrical part 90b that forms a tilt restricting surface 90a with an inner diameter slightly larger than the outer diameter of the outlet 1A, and a connecting flange part 90c that protrudes radially outward integrally from the outer peripheral surface of the tilt restricting 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 tilting restriction surface 90a of the tilting 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 flange 30.

[0040] 6, the tilt restricting body 90 is divided into two parts in the pipe circumferential direction and is composed of a pair of semicircular metal tilt restricting members 90A, 90B that are detachably attached to the insertion port 1A in the pipe radial direction. The pair of tilt restricting members 90A, 90B are configured in a circular shape that follows the outer peripheral surface 1a of the insertion port 1A by fastening 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 flange portions 90c of both split tilt-restricting members 90A, 90B are provided with tilt-restricting protrusions 95 that abut against the inner surface of the collar 30 as the opening 1A tilts relative to the pipe support portion 30d at one end of the collar 30 when the opening 1A and the socket 2A are disconnected and separated. These tilt-restricting protrusions 95 restrict further tilting of the opening 1A. The tilt-restricting protrusions 95 are provided at one or more locations on each connecting flange portion 90c. In this embodiment, the tilt-restricting protrusions 95 are formed to protrude radially outward from two locations on the circumference of each connecting flange portion 90c.

[0042] As shown in Fig. 2, the tilt-restricting cylindrical portions 90b of the split tilt-restricting members 90A, 90B are provided with engagement protrusions 90e that protrude from the pipe axis direction and 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. As shown in Fig. 3, the engagement protrusions 90e of the split tilt-restricting members 90A, 90B remain engaged with the tapered inner peripheral surface 22c of the pressure ring 22 even when the insertion port 1A and the socket 2A are disconnected from each other. In this disconnected state, the engagement between the engagement protrusions 90e of the split tilt-restricting members 90A, 90B and the tapered inner peripheral surface 22c of the pressure ring 22 restricts the tilt of the insertion port 1A relative to the pipe support portion 30d on one end of the flange 30.

[0043] As shown in FIGS. 2 and 6, the fixed connection portion 91 of the tilt restriction member 9 is formed by the first fastener 25 of the fitting connection portion 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 portions 90c of both split tilt restriction members 90A, 90B at locations corresponding to the T-head bolts 23 in the first fasteners 25. Fixed connection nuts 91b are screwed onto the tips of the T-head bolts 23 inserted into the bolt insertion holes 91a of both split tilt restriction members 90A, 90B. The fixed connection nuts 91b are tightened to fixedly connect the tilt restriction body 90 to the socket 2A.

[0044] As shown in Fig. 3, when the connection between the spigot 1A and the socket 2A is broken, bending forces due to earthquakes or uneven forces caused by fluid pressure may act on the spigot 1A, causing it to tilt relative to the pipe support portion 30d at one end of the collar 30, as shown in Fig. 4. At this time, the outer surface of the end of the spigot 1A abuts against the tilt restriction surface 90a of the tilt restriction body 90, and a tilt restriction protrusion 95 on a part of the tilt restriction body 90 abuts against the inner surface of the collar 30. This maintains the bending state between the spigot 1A and the pipe support portion 30d at one end of the collar 30 within an appropriate range in the disconnected state, thereby preventing fluid leakage due to a localized decrease in the sealing performance of the seal portion 35 in the circumferential direction.

[0045] The first separation prevention portion 4 of the first embodiment described above is configured to prevent separation movement between the socket 2A and the collar 30 by abutment between the abutment surface 41a of the separation prevention wall portion 41 provided in the collar 30 and the head 23A of each T-head bolt 23 fixed to the socket 2A side. However, this configuration is not limited to this. For example, in the case of a collar 30 that does not have a separation prevention wall portion 41, the first separation prevention portion 4, as explained with reference to Figures 2 and 3, is formed on the other end side in the pipe axial direction of the inner surface between the two pipe support portions 30d, 30e of the collar 30, in other words, on the side wall portion 30c on the other end side of the collar 30, so as to be able to abut against the tapered outer peripheral surface portion 2e of the outer peripheral surface 2c of the socket 2A from the pipe axial 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 separation prevention portion 4, when a separation 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 separation prevention portion 42 formed on the side wall portion 30c at the other end of the collar 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 separation between the two. At this time, the abutment surface 42a of the separation 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, so the abutment surface 42a of the separation prevention portion 42 and the tapered outer peripheral surface portion 2e of the socket 2A come into face-to-face contact, effectively preventing the socket 2A and the collar 30 from moving apart. Furthermore, when the abutment surface 42a of the separation prevention portion 42 abuts against the tapered outer peripheral surface portion 2e of the socket 2A, a force is generated that pushes open the divided surfaces of the split-structured collar 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 the two pipe support portions 30d, 30e of the collar 30, so the push-open force is reduced by the amount of deviation of the abutment surface 42a of the separation prevention portion 42 from the two pipe support portions 30d, 30e, and this makes it possible to suppress fluid leakage due to a decrease in the sealing performance of the seal portion 35 caused by the divided surfaces of the collar 30 being pushed open.

[0047] [Another connection structure of the tilt restriction body 90 of the first embodiment] In the first embodiment described above, as a first example of the tilt restrictor 90, as shown in FIG. 6, the connecting pieces 90d provided at both circumferential ends of the split tilt restrictor members 90A and 90B are connected to each other using fourth fasteners 92, such as bolts 93 and nuts 94. Instead of this connecting structure of the tilt restrictor 90, another connecting structure shown in FIG. 7 may be employed. In this connecting structure, second connecting pieces 90f are integrally formed at both circumferential ends of the split tilt restrictor members 90A and 90B, allowing them to be overlapped radially. Each pair of overlapping second connecting pieces 90f has a second bolt insertion hole 91c through which the tip of a T-head bolt 23 can be inserted. This allows the split tilt restrictor members 90A and 90B to be connected in an annular shape using the T-head bolts 23 and the fixing nuts 91b that constitute the fixing connecting portion 91 of the tilt restrictor 9.

[0048] [Second embodiment of tilt restriction body 90] In a 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 radial direction. Specifically, the tilt restricting protrusion 95 includes female thread portions 95A formed at two circumferential locations on each split tilt restricting member 90A, 90B, a tilt restricting bolt 95B that is threaded into the female thread portion 95A from the pipe radial direction, and a lock nut 95C that secures the tilt restricting bolt 95B, the contact position of which in the pipe radial direction is adjusted. The contact position with the inner surface of the joint ring 30 can be changed in the pipe radial direction by threading the tilt restricting bolt 95B.

[0049] When the tilt restricting body 90 having the split structure of the tilt restricting unit 9 is fitted to the insertion port 1A, there are cases where the socket 2A and the insertion port 1A are bent at the fitting connection 20. Even in such cases, the contact position of the tilt restricting bolt 95B can be changed in the pipe diameter direction according to the measured distance between the tip of the tilt restricting bolt 95B of the tilt restricting body 90 and the protruding contact portion on the inner peripheral surface 30f of the joint ring 30. This allows efficient and reliable attachment of the tilt restricting unit 9 to the insertion port 1A, even in cases where the socket 2A and the insertion port 1A are bent at the fitting connection 20. Furthermore, when a bending force due to an earthquake or uneven force caused by fluid pressure is applied in the detached state, the tilt restricting bolt 95B of the tilt restricting body 90 can be accurately fitted to the inner surface of the joint ring 30.

[0050] Second Embodiment In the second embodiment of the pipe connection separation prevention structure shown in Figures 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 Figure 10, when the connection between the spigot 1A and the socket 2A is released, bending forces caused by earthquakes or uneven forces due to fluid pressure act on the spigot 1A, causing it to tilt relative to the pipe support portion 30d at one end of the collar 30. At this time, the outer surface of the end of the spigot 1A abuts against the tilt restriction surface 90a of the tilt restriction body 90. This maintains the bending state between the spigot 1A and the pipe support portion 30d at one end of the collar 30 within an appropriate range in the separated state, thereby preventing fluid leakage due to localized deterioration in the sealing performance of the seal portion 35 in the circumferential direction. The other configurations are the same as those described in the first embodiment, so the same components are denoted by the same numbers as in the first embodiment and the description thereof will be omitted.

[0051] Third Embodiment 11 to 13, a third embodiment of the separation prevention structure for a pipe connection portion is configured as a T-shaped mechanical joint for the fitting connection portion 20 between the insertion port 1A of one fluid pipe 1 and the socket 2A of the other fluid pipe 2. This T-shaped mechanical joint is configured by fitting a third seal member 61 such as a rubber ring into an annular seal retaining groove 60 that is formed in the inner peripheral surface of the socket 2A and opens radially inward, and is compressed into a sealed (watertight) state between the outer peripheral surface 1a of the insertion port 1A that is fitted and connected to the socket 2A.

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

[0053] 13, the tilt restricting body 90 is divided into two parts in the pipe circumferential direction and comprises a pair of semicircular metal second split tilt restricting members 90C, 90D that are detachably attached to the insertion port 1A in the pipe radial direction. The pair of second split tilt restricting members 90C, 90D are configured in a circular shape that follows the outer peripheral 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] 11 and 13, each of the second split tilt-restricting members 90C, 90D is provided with a tilt-restricting protrusion 95 that, when the connection between the spigot 1A and the socket 2A is broken, abuts against the inner surface of the collar 30 as the spigot 1A tilts relative to the pipe support portion 30d at one end of the collar 30, thereby restricting further tilting of the spigot 1A. This tilt-restricting protrusion 95 is provided at one or more locations on each of the split tilt-restricting members 90A, 90B. In this embodiment, the tilt-restricting protrusions 95 are formed to protrude outward along the pipe diameter direction from two locations on the circumference of each of the split tilt-restricting members 90A, 90B.

[0055] The tilt-restricting protrusions 95 are configured so that their contact positions with the inner surface of the joint ring 30 can be changed in the pipe radial direction. Specifically, the tilt-restricting protrusions 95 include female threaded portions 95A formed at two circumferential locations on each of the split tilt-restricting members 90A, 90B, a tilt-restricting bolt 95B that is threadedly engaged with the female threaded portions 95A from the pipe radial direction, and a lock nut 95C that secures the tilt-restricting bolt 95B whose contact position in the pipe radial direction has been adjusted. The contact position with the inner surface of the joint ring 30 can be changed in the pipe radial direction by threading the tilt-restricting 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 peripheral 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 and 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 bearing ring 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 separation prevention portion 4 is provided which allows relative separation movement up to a separated state in which the receiving port 2A and the insertion port 1A are disconnected, and abuts to prevent relative separation movement between the receiving port 2A and the bearing ring 30 beyond a certain level in the separated state. 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 abutment portions 90h formed on the other ends of both second separate tilting restriction members 90C and 90D from the pipe axis direction on the inner peripheral surface 30f between the pipe support portions 30d and 30e of both split joint ring cases 30A and 30B. In this embodiment, the separation prevention wall portion 41 is formed at the boundary 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 control 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 control 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 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 abuts against the outer surface of the insertion port 1A, which tilts relative to the pipe support portion 30d at one end of the collar 30, thereby restricting the tilt of the insertion port 1A, and a tilt restricting protrusion 95 that abuts against the inner surface of the collar 30 as the insertion port 1A tilts relative to the pipe support portion 30d at one end of the collar 30, thereby restricting further tilt of the insertion port 1A. However, the present invention is not limited to this configuration, and for example, implementation may be made with only one of the tilt restricting surfaces 90a or the tilt restricting protrusion 95.

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

[0060] (3) In the first embodiment described above, the second removal prevention portion 5 is configured as an earthquake-resistant reinforcing bracket 50 having a separate structure from the collar 30, but the second removal prevention portion 5 may also be configured by being assembled to the collar 30. In this case, the pipe support portion 30d on one end side of the collar 30 in the pipe axial direction is provided with a removal prevention portion 55 that increases the resistance to removal between the pipe support portion 30d on one end side of the collar 30 and the outer peripheral 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 surface 2g Annular 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 30d tube support 60 Seal retaining groove 61 sealing member (third sealing member) 90 Tilt control body 90A Split tilt control member 90B Divided tilting restriction 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 socket of the other pipe section is fitted over both pipe sections, and a first separation prevention part is provided at the part that faces the insertion port side of the other pipe section in the pipe axial direction, which allows relative separation movement up to a separated state in which the socket and the insertion port are disconnected, and a first separation prevention part is provided that abuts and prevents relative separation movement between the socket and the collar beyond a certain level in the separated state, and a pipe support part side at one end of the collar in the pipe axial direction is provided with a first separation prevention part that abuts and prevents relative separation movement between the socket and the collar and the outer circumferential surface of the insertion port as the insertion port moves to separate. A second detachment prevention portion is provided with a stop portion that increases the stopping resistance, and a tilting control portion is provided within the flange that controls the tilting of the insertion port relative to the pipe support portion on one end side of the insertion port in the detached state, and the tilting control portion is provided with a tilting control body that is attached to the insertion port when the receiving port and the insertion port are fitted and connected and in the detached state, and has a tilting control surface that can abut against the outer surface of the insertion port that tilts in the detached state, and a fixed connecting portion that fixedly connects the tilting control body to the receiving port.

Images