Pipe joints and thrust transmission devices used when joining pipe joints

Abstract

In a construction method that involves propelling pipe joints during installation, the present invention provides a pipe joint that can improve workability when the pipeline is curved. [Solution] The system includes a thrust transmission device 4 that transmits the thrust F applied to the first pipe 1 to the thrust ring 3. The thrust transmission device 4 comprises a ring member 6 and a band member 5. The ring member 6 is fitted onto the insertion opening 11 and provided on the open end face 22 of the receiving opening 21. The band member 5 is fastened to the outer surface of the insertion opening 11. The ring member 6 engages with the open end face 22 of the receiving opening 21 in the circumferential direction of the pipe. The band member 5 is provided with a contact portion 53 that abuts against the ring member 6. The thrust F applied to the first pipe 1 is transmitted from the contact portion 53 of the band member 5 through the ring member 6 to the thrust ring 3.

Description

Technical Field

[0001] The present invention relates to a pipe joint and a thrust transmission tool used when joining pipe joints.

Background Art

[0002] Conventionally, a pipe joint having a seal member for inserting a spigot of a first pipe into a socket of a second pipe and sealing an outer surface of the spigot and an inner surface of the socket has been used. The seal member is pressed between the outer surface of the spigot and the inner surface of the socket by an end face of a pressing ring attached to the socket. The positional relationship is adjusted so that the spigot is in a predetermined position with respect to the socket, and a predetermined space is formed between the tip of the spigot and the inner end of the socket. The spigot is movable within this space in a sealed state, whereby the pipe joint can be contracted and bent and the required earthquake resistance performance is exhibited.

[0003] Here, in recent years, as a laying method of such a pipe joint, a pipe-in-pipe method (PIP method) that can be performed without excavation is often used. In the PIP method, a new pipe having a smaller diameter than the existing pipeline is arranged on the inlet side of the existing pipeline, and the new pipe is propelled inside the existing pipeline by applying thrust with a hydraulic jack or the like.

[0004] At this time, the new pipe is in a state of a pipe joint in which the positional relationship between the spigot and the socket is adjusted so that the required earthquake resistance performance can be exhibited, and thrust is applied to the first pipe in this state. Here, when the thrust applied causes the spigot to be further inserted into the socket and these positional relationships change, the required earthquake resistance performance cannot be exhibited.

[0005] Therefore, a thrust transmission tool as described in Patent Document 1 is used. The thrust transmission tool has a thrust transmission member that is fastened to the outer surface of the spigot and extends to the socket side, and the thrust transmission member abuts against the socket. Thereby, the thrust applied to the first pipe is transmitted to the socket via the thrust transmission tool. Therefore, the pipe joint is propelled in the pipeline without the spigot being further inserted into the socket.

[0006] The thrust ring has multiple through holes, and the thrust transmission member is inserted through these holes and contacts the socket. In other words, the thrust transmission member contacts the socket while avoiding the thrust ring. Therefore, the thrust applied to the first pipe is not transmitted to the thrust ring, nor is it transmitted to the sealing member via the thrust ring. As a result, the joint state of the pipe fitting does not change, and therefore the sealing performance is not affected. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2006-118655 [Overview of the project] [Problems that the invention aims to solve]

[0008] Here, when a pipe joint is pushed in the aforementioned pipeline, if the pipeline is bent in the middle, relative rotation (hereinafter referred to as relative rotation) may occur between the insertion end and the receiving end within the bent pipeline during the process of pushing the pipe joint. In contrast, with the thrust transmission device described in Patent Document 1, if such relative rotation occurs, the positional relationship in the rotational direction between the thrust transmission member and the thrust ring changes, and they may come into contact in the rotational direction. As a result, rotational force is applied to the thrust ring, and consequently, rotational force is also applied to the sealing member pressed against the end face of the thrust ring, which may change the sealing state and affect the sealing performance. In that case, the workability of the pipe will deteriorate, such as requiring readjustment of the joint state of the pipe joint.

[0009] This invention has been made in view of the above problems, and aims to provide a pipe joint that can improve workability when the pipeline is curved in a construction method in which pipe joints are propelled and laid. [Means for solving the problem]

[0010] The pipe joint according to this first invention is The insertion opening formed at the end of the first pipe is inserted into the receiving opening formed at the end of the second pipe. A pipe joint for laying a new pipeline, which is driven into an existing pipeline with a predetermined space formed between the tip of the insertion port and the inner end of the receiving port, An annular sealing member that seals the space between the outer surface of the insertion opening and the inner surface of the receiving opening, An annular pressing ring is fastened to the open end face of the socket and presses a sealing member between the outer surface of the insertion opening and the inner surface of the socket, A thrust transmission device that transmits the thrust applied to the first pipe in the insertion direction of the insertion port to the thrust ring while ensuring the predetermined space is maintained. Equipped with, The thrust transmission device is, A ring member that fits onto the opening, A band member fastened to the outer surface of the insertion opening and It has, The ring member engages with the open end face of the receiving port in the circumferential direction of the pipe and also contacts the end face of the thrust ring. The band member is provided with a contact portion that contacts the ring member. The thrust transmission device transmits the thrust applied to the first pipe to the thrust ring via a ring member from the contact portion of the band member.

[0011] According to this, in the pipe joint, the ring member engages with the open end face of the socket in the circumferential direction of the pipe, and the band member is fastened to the outer surface of the socket. Therefore, when the relative rotation between the socket and the socket occurs during the installation of the pipe joint, the ring member rotates with the open end face, and the band member rotates with the socket. In other words, the ring member and the band member rotate relative to each other. At this time, the contact portion of the band member remains in contact with the ring member, so the thrust applied to the first pipe is transmitted from the contact portion of the band member to the thrust ring via the ring member in the axial direction of the pipe. On the other hand, in the rotational direction, the band member and the ring member only rotate relative to each other, and almost no rotational force is acted from the band member to the ring member, so almost no rotational force is acted on the thrust ring and the sealing member. Therefore, even when the relative rotation between the socket and the thrust ring occurs, the sealing performance is not affected, and the required sealing performance is maintained.

[0012] The pipe joint according to this second invention has a contact portion of the thrust ring that contacts the open end face of the socket.

[0013] Conventionally, the amount of pressure applied to the sealing member by the thrust ring was controlled by managing the tightening torque when fastening the thrust ring to the open end face of the socket. According to the second invention, the pipe joint can be configured such that the amount of pressure applied to the sealing member when the contact portion of the thrust ring contacts the open end face is the required amount, for example, by adjusting the length of the contact portion in the direction of the pipe axis. As a result, even if the thrust applied to the first pipe is transmitted to the thrust ring in the direction of the pipe axis via the thrust transmission device, the amount of pressure applied to the sealing member by the thrust ring does not change, and therefore the sealing performance is not affected.

[0014] The pipe joint according to this third invention is characterized in that the ring member and the band member are each separable in the circumferential direction.

[0015] According to this, the pipe joint improves workability by allowing the thrust transmission device to be attached after the spigot and socket have been joined.

[0016] The opening end face of the socket of the pipe joint according to the fourth invention is provided with a plurality of socket insertion holes that penetrate in the direction of the pipe axis, The ring member is provided with an insertion portion that is inserted into the receiving insertion hole.

[0017] According to this, in the thrust transmission device of the pipe joint, the insertion portion of the ring member is inserted into the insertion hole of the socket, thereby engaging the ring member and the open end face of the socket in the circumferential direction of the pipe. In other words, the ring member can be engaged with the open end face with a simple configuration and simple operation, improving workability.

[0018] The ring member of the pipe joint according to the fifth invention is such that multiple insertion portions are inserted into the receiving insertion hole, thereby centering the ring member with respect to the opening end face, and a predetermined gap is provided in the diameter direction of the pipe between the inner surface of the centered ring member and the outer surface of the insertion port.

[0019] According to this, in the pipe joint, since a plurality of insertion portions are inserted into the insertion holes of the receiving port, the ring member is centered with respect to the receiving port, and a predetermined gap is provided between the inner side thereof and the insertion port. Therefore, since the inner surface of the ring member and the outer surface of the insertion port do not contact each other, when the relative rotation between the insertion port and the receiving port occurs, the relative rotation is not hindered. Therefore, the pipe joint can be smoothly propelled even when the pipeline is bent, and the workability is improved.

[0020] In a part of the end face of the pressing ring of the pipe joint according to the sixth invention, a reinforcing rib that protrudes in the pipe axis direction to reinforce the pressing ring is provided. On the end face of the ring member, a recessed portion that recesses in the pipe axis direction is provided at a position corresponding to the position of the reinforcing rib.

[0021] According to this, even when a reinforcing rib is provided on the end face of the pressing ring of the pipe joint, due to the provision of a recessed portion at a position corresponding to the reinforcing rib, the end face of this recessed portion can be configured to abut against the end face of the reinforcing rib. Therefore, the thrust applied to the first pipe is transmitted from the abutting portion to the pressing ring.

[0022] The thrust transmission tool according to the seventh invention has an insertion port formed at the end of the first pipe inserted into a receiving port formed at the end of the second pipe, an annular sealing member that seals between the outer surface of the insertion port and the inner surface of the receiving port, and an annular pressing ring fastened to the opening end face of the receiving port to press the sealing member between the outer surface of the insertion port and the inner surface of the receiving port. It is provided with and is a thrust transmission tool used for a pipe joint that is propelled in an existing pipeline to lay a new pipeline in a state where a predetermined space is formed between the tip of the insertion port and the inner end of the receiving port. It has a ring member externally fitted to the insertion port, and a band member fastened to the outer surface of the insertion port. It has The ring member engages with the opening end face of the receiving port in the pipe circumferential direction and abuts against the end face of the pressing ring. The band member is provided with a contact portion that contacts the ring member. The thrust applied to the first pipe is transmitted from the contact portion of the band member to the thrust ring via the ring member.

[0023] According to this, the thrust transmission device can achieve the same effects as the present first invention. [Effects of the Invention]

[0024] According to the present invention, in a construction method for laying pipe joints by pushing them forward, the workability when the pipeline is curved can be improved. [Brief explanation of the drawing]

[0025] [Figure 1] This is a cross-sectional view of a pipe joint in which the thrust transmission device according to the present invention is used. [Figure 2] This is a plan view of the thrust ring provided by the pipe joint. [Figure 3] This is a perspective view of a pipe joint showing how the pipe joint is installed using a thrust transmission device according to an embodiment of the present invention. [Figure 4] This is a perspective view of the band member of the thrust transmission device. [Figure 5] This is an exploded view of the band component. [Figure 6] This is a perspective view of the ring member of the thrust transmission device. [Figure 7] This is a perspective view of the ring member, seen from the opposite side of Figure 6. [Figure 8] This is an exploded view of the ring component. [Figure 9] This is a cross-sectional view along line AA in Figure 3. [Figure 10] This is a cross-sectional view along line BB in Figure 9. [Figure 11] This is a cross-sectional view along the CC line in Figure 9. [Figure 12] This is a cross-sectional view along the DD line in Figure 9. [Modes for carrying out the invention]

[0026] Hereinafter, a pipe joint 100 according to an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts will be denoted by the same reference numerals to avoid repetition in the description. In the following description, terms such as "up," "down," "horizontal," and "vertical" may be used to indicate position or direction. These terms are used for convenience to facilitate understanding of the embodiment and are not limited to the position or direction in actual implementation.

[0027] <Embodiment 1> [Configuration of pipe fitting 100] Referring to Figure 1, the configuration of a pipe joint 100 in which the thrust transmission device 4 according to Embodiment 1 of the present invention is used will be described. As shown in Figure 1, the pipe joint 100 has a socket 11 formed in the first pipe 1 and a socket 21 formed in the second pipe 2, with the socket 11 being inserted into the socket 21. For example, ductile iron pipes are used for these pipes. Hereinafter, the insertion direction of the socket 11 in the direction of the pipe axis may be simply referred to as the "insertion direction" or "rear side," and the disengagement direction of the socket 11 in the direction of the pipe axis may be simply referred to as the "disengagement direction" or "front side."

[0028] A lock ring housing groove 24 is formed around the entire circumference of the inner circumferential surface of the socket 21. A lock ring 9 is housed in the lock ring housing groove 24. The lock ring 9 is a one-piece ring (not shown) with a cut in one place along the circumferential direction.

[0029] A projection 12 is formed around the entire circumference of the insertion port 11. The projection 12 catches on the lock ring 9 from the back of the receiving port 21 when the insertion port 11 is released, preventing the insertion port 11 from coming off the receiving port 21 and providing the required anti-detachment performance.

[0030] A predetermined space S is formed between the tip of the insertion port 11 and the inner end of the receiving port 21. This allows the insertion port 11 to move within the predetermined space S, enabling the pipe joint 100 to bend and exhibit the required seismic resistance.

[0031] A seal ring 7 (an example of a sealing member) is provided at a location closer to the open end face 22 of the socket 21 than the lock ring 9, which is compressed in the radial direction of the pipe to seal the space between the outer circumferential surface of the insertion port 11 and the inner circumferential surface of the socket 21. The seal ring 7 is a rubber ring.

[0032] An annular backup ring 8 is provided between the lock ring 9 and the seal ring 7. The backup ring 8 centers the insertion opening 11 relative to the socket 21.

[0033] The end of the seal ring 7 on the side facing the release direction is fitted into a seal ring fitting portion 37 provided on the end face of the thrust ring 3, and is also pressed in the insertion direction from the thrust ring 3. The seal ring 7 is pushed between the outer circumferential surface of the insertion opening 11 and the inner circumferential surface of the receiving opening 21 when the thrust ring 3 is attached to the open end face 22 of the receiving opening 21. The thrust ring 3 is provided with a plurality of thrust ring insertion holes 31, and the open end face 22 is provided with receiving opening insertion holes 23 at positions corresponding to the thrust ring insertion holes 31. The thrust ring 3 is attached to the open end face 22 by passing a T-head bolt T through the thrust ring insertion holes 31 and the receiving opening insertion holes 23 and tightening a nut N.

[0034] A first contact portion 32 protruding in the direction of the pipe axis is provided on the outer side of the thrust ring insertion hole 31 in the pipe radial direction of the thrust ring 3, and a second contact portion 33 protruding in an annular shape in the direction of the pipe axis is provided on the inner side of the thrust ring insertion hole 31 in the pipe radial direction. The attachment of the thrust ring 3 to the receiving opening 21 is completed when the first contact portion 32 and the second contact portion 33 come into contact with the open end face 22. The amount of protrusion of the first contact portion 32 and the second contact portion 33 is set to a value corresponding to the required amount of indentation in the seal ring 7.

[0035] Conventionally, the amount of pressure applied to the seal ring 7 by the thrust ring 3 was adjusted by managing the tightening torque of the nut N (fastening member). By setting the protrusion amounts of the first contact portion 32 and the second contact portion 33 to values ​​corresponding to the required amount of pressure applied to the seal ring 7, the pressure applied to the seal ring 7 is completed by tightening the fastening member until the first contact portion 32 and the second contact portion 33 contact the open end face 22. This eliminates the need to manage the tightening torque of the fastening member, improving the ease of pipe installation.

[0036] As shown in Figure 2, the thrust ring 3 has a plurality of protrusions 34 that project in the diameter direction of the pipe on its outer circumferential surface. The thrust ring insertion hole 31 is provided through the protrusions 34. As shown in the figure, the spacing between adjacent thrust ring insertion holes 31 at the bottom of the thrust ring 3 (corresponding central angle: φ2) is set to be greater than the spacing between adjacent thrust ring insertion holes 31 at the top of the thrust ring 3 (corresponding central angle: φ1). The central angle φ2 is set to be, for example, about 90°. As a result, an enlarged spacing portion 38 is formed at the bottom of the thrust ring 3. The thrust ring 3 is provided with a reinforcing rib 35 in this portion. The reinforcing rib 35 is an arc-shaped member provided on the end face 30 opposite to the surface that presses the seal ring 7, and protrudes from this end face in the detached direction by a predetermined dimension L (see Figure 1). The range of central angles corresponding to the area where the reinforcing rib 35 is arranged is set to be equivalent to the central angle φ2 corresponding to the enlarged spacing portion.

[0037] With the configuration of the thrust ring 3 described above, even if there are obstacles such as walls in the pipeline laying groove when attaching the thrust ring 3 to the socket 21, the workability of fastening the T-head bolt T and nut N is improved by positioning the enlarged spacing portion 38 opposite the obstacle. At this time, since the thrust ring 3 is kept rigid because the reinforcing rib 35 is placed in the enlarged spacing portion 38, deflection and deformation of the enlarged spacing portion 38 of the thrust ring 3 are prevented even when the reaction force of the seal ring 7 acts on the thrust ring 3.

[0038] Referring to Figure 3, an overview of the method for laying the pipe joint 100 using the thrust transmission device 4 according to an embodiment of the present invention will be described (details will be given later). To reiterate, the socket insertion holes 23 are provided in positions corresponding to the thrust ring insertion holes 31. However, in this embodiment, there are more socket insertion holes 23 than thrust ring insertion holes 31 from the viewpoint of ease of attaching the thrust ring 3 to the socket 21. Hereinafter, the socket insertion holes 23 that are not used for attaching the thrust ring 3 will be referred to as unused insertion holes 23U.

[0039] The thrust transmission device 4 according to this embodiment consists of a band member 5 provided on the outer surface of the insertion port 11 and a ring member 6 provided on the open end face 22 of the receiving port 21. The thrust F applied to the first pipe 1 (insertion port 11) is transmitted to the thrust ring 3 via the band member 5 and the ring member 6.

[0040] The present invention aims to improve the workability of a pipe joint 100 when a thrust transmission device 4 is used to install a pipe joint 100 in an existing pipeline P as shown in the figure, without affecting the sealing performance even when relative rotation (relative rotation) occurs between the insertion port 11 and the receiving port 21 as described above.

[0041] [Configuration of the thrust transmission device 4] The configuration of the thrust transmission device 4 will be explained with reference to Figures 4 to 8. First, the configuration of the band member 5 of the thrust transmission device 4 will be explained with reference to Figures 4 and 5.

[0042] As shown in the figure, the band member 5 is a cylindrical member made of metal and divided into four sections in the circumferential direction, and is composed of four equally divided band pieces 51. Each divided band piece 51 has a rectangular cross-section and a thin plate-like main body, and band connecting plates 52 extending radially outward are erected at both ends thereof for connecting each divided band piece 51. Each band connecting plate 52 is fastened to each other with fastening elements such as bolts B and nuts N to assemble into a cylindrical shape.

[0043] As shown in Figure 4, each band connecting plate 52 is configured to have a predetermined spacing in the circumferential direction when assembled in a ring shape, and within that spacing, it is tightened with a predetermined tightening torque by fastening elements on the outer surface of the insertion opening 11. In this way, the band member 5 is fastened on the outer surface of the insertion opening 11. The predetermined tightening torque is set considering the "required axial force acting on the pipe to ensure seismic performance" which will be described later. Multiple ribs 54 are provided between each band connecting plate 52 and the main body, reinforcing the circumferential tilting strength of the band connecting plates 52 when they are fastened together.

[0044] When the band connecting plates 52 are fastened together and assembled into a cylindrical shape on the outer surface of the insertion opening 11, the axial ends of each band connecting plate 52 function as contact portions 53 that come into contact with the ring member 6.

[0045] Next, the configuration of the ring member 6 will be described with reference to Figures 6 to 8. As shown in the figures, the ring member 6 is an annular member divided into three circumferential sections, and is composed of three divided ring pieces 63, 63, and 64. Each divided ring piece 63, 63, and 64 has a rectangular cross-section and, in this embodiment, is composed of, for example, two short ring pieces 63, 63 and one long ring piece 64. The short ring pieces 63 are configured to have a smaller central angle than the long ring piece 64. In this embodiment, for example, the central angle θ1 of the short ring piece 63 is 103°, and the central angle θ2 of the long ring piece 64 is, for example, 154° (see Figure 8). By configuring the ring member 6 so that the central angles θ1 of the short ring pieces 63 and the central angle θ2 of the long ring piece 64 are different, good identifiability can be achieved, thereby improving the workability of the pipe. The central angle θ2 of the long ring piece 64 is configured to be larger than the central angle φ2 (approximately 90°) of the reinforcing rib 35 of the thrust ring 3.

[0046] At both ends of each segmented ring piece 63, 63, 64, connecting ring plates 65 are erected, extending radially outward. The ring connecting plates 65 are fastened together with fastening elements such as bolts B and nuts N to assemble them into a ring shape.

[0047] The short ring piece 63 is provided with an engaging portion 66 that engages with the thrust ring 3. The engaging portion 66 consists of a main body that protrudes radially outward from the short ring piece 63 and a cylindrical insertion portion 67 that extends axially from the main body. In this embodiment, one insertion portion 67 is provided on each of the two short ring pieces 63, 63, so that two are provided on the assembled ring member 6. However, more than one insertion portion 67 may be provided on the short ring piece 63.

[0048] The insertion portion 67 is configured to be positioned in a location corresponding to the receiving insertion hole 23 of the receiving end 21 when each divided ring piece 63, 63, 64 is fastened on the outer surface of the insertion opening 11 and assembled into a ring shape. By inserting the insertion portion 67 into the unused insertion hole 23U (see Figure 3) of the receiving insertion hole 23 of the receiving end 21, the ring member 6 engages with the open end face 22 of the receiving end 21 in the circumferential direction of the pipe.

[0049] Furthermore, the insertion portions 67 are positioned so that the ring member 6 can be centered relative to the open end face 22 of the receiving opening 21, by inserting the two insertion portions 67 of the assembled ring member 6 into the unused insertion holes 23U of the receiving opening 21. A predetermined gap G may be provided between the inner surface of the centered ring member 6 and the outer surface of the insertion opening 11, which is shown by the dashed line.

[0050] Each long ring piece 64 is configured such that its axial width is shorter than that of the short ring piece 63 by a predetermined length L of the protruding reinforcing rib 35 (see Figures 6 and 7). That is, when the divided ring pieces 63, 63, 64 are assembled in a ring shape, the end face of the long ring piece 64 is recessed by a predetermined length L compared to the end face of the short ring piece 63. The recessed portion 68 is formed on the end face in the same direction as the insertion portion 67 extends in the axial direction.

[0051] In the following explanation, when the ring member 6 is engaged with the open end face 22 of the receiving opening 21, the end face of the ring member 6 facing the open end face 22 of the receiving opening 21 will be referred to as the "receiving opening side end face 61," and the end face facing the opposite direction in the axial direction from the receiving opening side end face 61 will be referred to as the "anti-receiving opening side end face 62." In this embodiment, the ring member 6 is made of a resin such as polypropylene.

[0052] [Function of thrust transmission device 4] The operation of the thrust transmission device 4 will be explained with reference to Figures 9 (cross-sectional view in direction AA of Figure 3) through 12. In Figure 9, for explanatory purposes, the band member 5 and the ring member 6 are assumed to be in a positional relationship in the diameter direction of the pipe as shown. However, the positional relationship between the band member 5 and the ring member 6 is not limited to the positional relationship shown.

[0053] At this time, Figures 10 (a cross-sectional view along line BB in Figure 9) and 11 (a cross-sectional view along line CC in Figure 9) show the location where the contact portion 53 of the band member 5 is in contact with a part of the short ring piece 63 of the ring member 6 in a longitudinal cross-sectional view. As shown in the figures, the contact portion 53 of the band member 5 is in contact with the end face 62 of the ring member 6 that is not facing the receiving port, and the end face 61 of the ring member 6 is in contact with the end face 30 of the thrust ring 3. Therefore, the thrust F applied to the first pipe 1 imparts thrust from the contact portion 53 of the band member 5 to the ring member 6, and from the ring member 6 to the thrust ring 3, and this thrust is transmitted to the receiving port 21 via the second contact portion 33 (and first contact portion 32) of the thrust ring 3. As shown in the figure, the insertion portion 67 is inserted into the unused insertion hole 23U with a predetermined gap, so thrust is not transmitted between the outer surface of the insertion portion 67 material and the inner surface of the unused insertion hole 23U.

[0054] Figure 12 (a cross-sectional view along the DD line in Figure 9) shows the point where the contact portion 53 of the band member 5 is in contact with a part of the long ring piece 64 of the ring member 6. As shown in the figure, the contact portion 53 of the band member 5 is in contact with the end face 62 of the ring member 6 that is not facing the receiving port, and the recessed portion 68 of the ring member 6 is in contact with the end face 36 of the reinforcing rib 35 of the thrust ring 3. Therefore, the thrust F applied to the first pipe 1 imparts thrust from the contact portion 53 of the band member 5 to the ring member 6, and also imparts thrust from the recessed portion 68 (receiving port end face 61) of the ring member 6 to the end face 36 of the reinforcing rib 35 of the thrust ring 3, and this thrust is transmitted to the receiving port 21 via the first contact portion 32 and the second contact portion 33 of the thrust ring 3.

[0055] As described above, the recessed portion 68 is configured such that the amount of recess is equal to a predetermined length L (see Figure 1) of the protruding reinforcing rib 35, and the central angle θ2 (154°) of the long ring piece 64 is configured to be greater than the central angle φ2 (approximately 90°) corresponding to the area where the reinforcing rib 35 is arranged. As a result, the end face of the recessed portion 68 is in proper contact with the end face 36 of the reinforcing rib 35. Consequently, the receiving end face 61 of the ring member 6 is in proper contact with the opening end face 22 of the receiving end 21, even if the reinforcing rib 35 is provided on the opening end face 22. Therefore, the thrust F applied to the first pipe 1 is efficiently transmitted to the receiving end 21.

[0056] The above action is the same even when relative rotation occurs between the insertion port 11 and the receiving port 21. That is, when the relative rotation occurs, the band member 5 rotates together with the insertion port 11 (see, for example, the dashed line in Figure 9) because it is fastened to the outer surface of the insertion port 11. On the other hand, the ring member 6 rotates together with the receiving port 21 because its engaging portion 66 is engaged with the opening end face 22 of the receiving port 21 in the circumferential direction. Even if the relative positional relationship between the band member 5 and the ring member 6 in the circumferential direction of the pipe changes, the contact portion 53 of the band member 5 can still contact the end face 62 of the ring member 6 that is not the receiving port in the same way.

[0057] As the ring member 6 rotates together with the receiving opening 21, the relative position of the receiving opening 21 with respect to the open end face 22 remains unchanged. As a result, the recessed portion 68 of the ring member 6 is held in a position corresponding to the reinforcing rib 35 on the open end face 22. Therefore, even when the relative rotation occurs, the recessed portion 68 of the ring member 6 remains in contact with the reinforcing rib 35.

[0058] As a result, even when the aforementioned relative rotation occurs, the thrust F applied to the first pipe 1 is transmitted from the contact portion 53 of the band member 5 to the thrust ring 3 via the ring member 6. In other words, in the pipe joint 100, the thrust F applied to the first pipe 1 is efficiently transmitted to the socket 21 and not to the seal ring 7. Therefore, the sealing performance is not affected even when the aforementioned relative rotation occurs. This improves the workability when laying the pipe joint 100, especially when the pipeline is curved.

[0059] Furthermore, when thrust is applied to the insertion port 11 and the receiving port 21 rotate relative to each other, the contact portion 53 of the band member 5 may change positional relationship while in contact with the end face 62 of the ring member 6 opposite the receiving port. In this case, because the ring member 6 is made of resin, the frictional force at the point where the contact portion 53 of the band member 5 contacts the end face 62 of the ring member 6 opposite the receiving port is suppressed. Thus, the pipe joint 100 is propelled smoothly even in a curved pipe by being configured to facilitate the relative rotation. In addition, this also suppresses the rotational force from the contact portion 53 of the band member 5 to the ring member 6.

[0060] Furthermore, when the engaging portion 66 of the ring member 6 engages with the open end face 22, the ring member 6 is centered with respect to the open end face 22, and a predetermined gap G is provided between the inner surface of the ring member 6 and the outer surface of the insertion opening 11. This prevents contact between the ring member 6 and the outer surface of the insertion opening 11 when the relative rotation occurs. Thus, the pipe joint 100 is smoothly advanced even in curved pipelines by being configured to facilitate the relative rotation.

[0061] [Effects of the thrust transmission device 4 on seismic resistance] For example, in situations where it is necessary to contract or bend the pipe joint 100 to follow the movement of the ground, such as during an earthquake, the thrust transmission device 4 causes the band member 5 to slide and move on the outer surface of the insertion opening 11, thereby causing the insertion opening 11 to contract or bend relative to the receiving opening 21.

[0062] In other words, the thrust transmission device 4 is fastened to the insertion opening 11 so that the band member 5 can move on the insertion opening 11 when the required axial force is applied to the band member 5 from the receiving opening 21 via the ring member 5 as the pipe joint 100 contracts or bends. More specifically, the fastening load when fastening the band connecting plate 52 described above is designed so that a fastening force is obtained that allows the band member 5 to move (slide) on the insertion opening 11 when the required axial force is applied.

[0063] Furthermore, in cases where it is necessary to propel the thruster 4 over a long distance within a pipeline, the thruster 4 may be used with the band member 5 fixed to the outer surface of the insertion opening 11 in order to restrict the movement of the band member 5 on the insertion opening 11.

[0064] In such cases, when the required axial force is applied to the pipe, the resin ring member 6 breaks starting from the point where it contacts the contact portion 53 of the band member 5. As a result, the insertion opening 11 shrinks or bends relative to the receiving opening 21 by the length of the ring member 6 in the axial direction of the pipe.

[0065] In other words, the thrust transmission device 4 is designed in terms of material strength, dimensions, etc., such that the ring member 6 can be destroyed when the required axial force acting on the pipe is applied.

[0066] As described above, the pipe joint 100 is configured to improve workability within the pipeline while also being able to exhibit the required seismic resistance performance in emergencies such as earthquakes.

[0067] <Other Embodiments> In the above embodiment, the band member 5 and the ring member 6 were constructed by dividing them into four and three sections in the circumferential direction, respectively. However, the number of divisions is not limited to this, and any number of divisions may be set, for example, depending on the nominal diameter of the pipe joint 100. Even with this configuration, the contact portion 53 of the band member 5 can contact the ring member 6 in the same way as in the above embodiment, thereby achieving the same effects as described above.

[0068] Furthermore, in the above embodiment, the thrust ring 3 is provided with a first contact portion 32 and a second contact portion 33. However, the thrust ring 3 may be configured to have either the first contact portion 32 or the second contact portion 33. Even with this configuration, the thrust ring 3 can contact the open end surface 22 of the receiving opening 21, thereby achieving the same effects as in the above embodiment.

[0069] Furthermore, although the ring member 6 was made of resin in the above embodiment, the ring member 6 is not limited to being made of resin, and may be made of metal, for example. Even with this configuration, the contact portion 53 of the band member 5 can contact the ring member 6 in the same way as in the above embodiment, thereby achieving the same effects as described above.

[0070] Furthermore, the ring member 6 may be provided with a friction-reducing material (for example, a resin cover, a resin coating, etc.) on its surface (the end face 62 opposite the receiving end). This suppresses the frictional force at the point where the contact portion 53 of the band member 5 contacts the end face 62 of the ring member 6, regardless of the material of the ring member 6, thus achieving the same effects as in the above embodiment.

[0071] Embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the embodiments described above, and can be implemented in various forms without departing from the spirit of the invention. The drawings schematically show each component in order to facilitate understanding, and the thickness, length, number, spacing, etc. of each component shown may differ from the actual dimensions due to the convenience of drawing creation. Furthermore, the material, shape, dimensions, etc. of each component shown in the above embodiments are examples and are not particularly limited, and various modifications are possible without substantially departing from the configuration of the present invention. [Explanation of Symbols]

[0072] 1. First tube 11 Socket 2. The second tube 21 socket 22 Open end face 23 Receptacle insertion hole 3. Pressing ring 31 Reinforcement Ribs 4. Thrust transmission device 5 Band members 51 divided band pieces 52 Band Connection Plate 53 Contact part 6 Ring Member 61 Socket side end face 62 End face opposite to socket 63 Short ring pieces 64 long ring pieces 66 Engaging part 67 Insertion part 68 Recessed area 7 Seal ring 100 Pipe Fittings

Claims

1. The insertion opening formed at the end of the first pipe is inserted into the receiving opening formed at the end of the second pipe. A pipe joint for laying a new pipeline, which is driven into an existing pipeline with a predetermined space formed between the tip of the insertion port and the inner end of the receiving port, An annular sealing member that seals the space between the outer surface of the insertion opening and the inner surface of the receiving opening, An annular pressing ring is fastened to the open end face of the socket and presses a sealing member between the outer surface of the insertion opening and the inner surface of the socket, A thrust transmission device that transmits the thrust applied to the first pipe in the insertion direction of the insertion port to the thrust ring while ensuring the predetermined space is maintained. Equipped with, The thrust transmission device is, A ring member that fits onto the opening, A band member fastened to the outer surface of the insertion opening and It has, The ring member engages with the open end face of the receiving port in the circumferential direction of the pipe and also contacts the end face of the thrust ring. The band member is provided with a contact portion that contacts the ring member. The thrust transmission device is a pipe joint characterized by transmitting the thrust applied to the first pipe from the contact portion of the band member to the thrust ring via the ring member.

2. The pipe joint according to claim 1, characterized in that the thrust ring has a contact portion that contacts the open end face of the socket.

3. The pipe joint according to claim 1, characterized in that the ring member and the band member are each divisible in the circumferential direction.

4. The open end face of the socket is provided with multiple socket insertion holes that penetrate in the direction of the pipe axis. The pipe fitting according to claim 1, characterized in that the ring member is provided with an insertion portion that is inserted into a receiving insertion hole.

5. The pipe joint according to claim 4, characterized in that the ring member is centered with respect to the open end face by having a plurality of insertion portions inserted into the receiving insertion hole, and a predetermined gap is provided in the diameter direction of the pipe between the inner surface of the centered ring member and the outer surface of the insertion portion.

6. A reinforcing rib is provided on a portion of the end face of the thrust ring, protruding in the direction of the pipe axis to reinforce the thrust ring. The pipe joint according to any one of claims 1 to 5, characterized in that the end face of the ring member is provided with a recess that is recessed in the direction of the pipe axis at a position corresponding to the position of the reinforcing rib.

7. The insertion opening formed at the end of the first pipe is inserted into the receiving opening formed at the end of the second pipe. An annular sealing member that seals the space between the outer surface of the insertion opening and the inner surface of the receiving opening, An annular pressing ring is fastened to the open end face of the socket, and presses a sealing member between the outer surface of the insertion opening and the inner surface of the socket. Equipped with, A thrust transmission device used in a pipe joint for laying a new pipeline, which is propelled within an existing pipeline with a predetermined space formed between the tip of the insertion port and the inner end of the receiving port, A ring member that fits onto the opening, A band member fastened to the outer surface of the insertion opening and It has, The ring member engages with the open end face of the receiving port in the circumferential direction of the pipe and also contacts the end face of the thrust ring. The band member is provided with a contact portion that contacts the ring member. A thrust transmission device characterized by transmitting the thrust applied to the first pipe from the contact portion of the band member to the thrust ring via the ring member.

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