Joining method and joining material

Abstract

To provide a joining method and a joining member which facilitates centering of a second pipe and a first pipe and can shorten work time in an excavated trench without being affected by the level of skill of a worker.SOLUTION: A joining method for joining a first pipe and a second pipe into which inner diameter part the first pipe is inserted and which has an increased diameter part formed with a larger diameter than an outer diameter of the first pipe, the joining method comprising the steps of: fixing the first pipe to a fixing part; attaching, to the fixing part, an arm part protruding in a direction of the second pipe; making an abutment part formed at the arm part abut on the increased diameter part such that the abutment part protrudes from an end part of the increased diameter part in a direction of the second part; attaching a reaction force member to the first pipe; attaching a joining member to the fixing part; and inserting the second pipe into the inner diameter part by operating the joining member.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a joining method and joining member used when assembling pipe members, particularly when joining cast iron pipes together. [Background technology]

[0002] Conventionally, various methods have been known for burying water supply and sewerage pipes, and methods such as open cut and jacking have been used.

[0003] The open cut method involves directly excavating the ground to create a trench, forming a foundation in the trench, installing multiple pipes that will become new pipes, and then joining the multiple pipes together to lay them down.

[0004] When fitting the insertion port of one of multiple pipes into the receiving port of another pipe, it is necessary to perform centering and positioning work on the pipes to ensure smooth installation of the new pipe.

[0005] This centering and positioning work involves hanging one pipe from outside the excavation trench using a crane such as a Unic and dropping it into the excavation trench, and then aligning the other pipe that has already been laid with the newly installed one, and assisting the position of the other pipe, all done manually by workers in the excavation trench and the crane operator working together.

[0006] However, this manual centering and positioning of the joining pipes requires a lot of time in the excavation trench and a large number of people, making it difficult to reduce the number of work steps, so a method that can easily perform the centering and positioning work was needed.In addition, the work requires visual inspection by the worker, and the centering position must be maintained while the pipe is suspended, so the worker's skill is required, and there are also problems that the centering and positioning work cannot be performed easily.

[0007] Furthermore, the conventional method for joining new pipes involves attaching band members to the socket of the other pipe and the insertion port of one pipe, and then pulling the band members together with a ratchet-type joining device to join the insertion port of one pipe to the socket of the other pipe.

[0008] Various centering structures for pipe members are known. For example, as described in Patent Document 1, a structure is known which comprises a ring-shaped jig body formed by joining multiple divided arc-shaped members using a joining means so that it can be detachably attached to the outer periphery of the opposing end of one of two steel pipes to be connected, multiple arms attached to the jig body and extending toward the other steel pipe, and screw adjustment rods that are screwed onto the tip of each arm and can be moved forward and backward toward the central axis of the steel pipe, and the tips of the multiple screw adjustment rods press against the outer surface of the other steel pipe to align the central axes of the two steel pipes.

[0009] According to this centering structure, since it is not necessary to weld an erection piece to the steel pipe, the work efficiency in the welding joint of the steel pipe is significantly improved, and the quality of the welding joint of the steel pipe can be improved. Furthermore, since the centering jig of the present invention can be used repeatedly, it has the effect of being extremely advantageous in reducing costs in the welding joint of the steel pipe. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-263292 Summary of the Invention [Problem to be solved by the invention]

[0011] However, in conventional centering structures, the outer diameters of the opposing steel pipes are the same because the centering is performed to weld the joint ends together.In contrast, in joint pipes using ductile cast iron pipes or the like, the insertion end of one pipe is inserted into the socket of the other pipe that has already been laid by moving it axially, so there was a problem that the outer diameters of the socket and the insertion end are different, making it impossible to apply the conventional centering structure.

[0012] Furthermore, as mentioned above, the open cut method involves suspending the new pipe in the excavation trench using a crane or similar device. In order to shorten the time required for work in the excavation trench, there was a need to easily perform the centering and positioning work of one pipe with another pipe that has already been laid simply by lowering the pipe to be laid later into the excavation trench.

[0013] Therefore, the present invention has been made in consideration of the above problems, and aims to provide a joining method and joining member that can easily center the second pipe and the first pipe and can shorten the work time in the excavation trench regardless of the worker's level of skill. [Means for solving the problem]

[0014] A joining method according to the present invention is a method for joining a first pipe to a second pipe, the second pipe having an inner diameter portion into which the first pipe is inserted and an expanded diameter portion formed to be larger than the outer diameter of the inserted portion of the first pipe, the method comprising the steps of: fixing a fixing portion to the first pipe; and attaching an arm portion to the fixing portion, the arm portion protruding toward the second pipe. When the tip of the insertion portion of the first pipe is positioned at the end of the enlarged diameter portion of the second pipe, the arm portion Tip a contact portion formed on the enlarged diameter portion, the contact portion protruding from the end of the enlarged diameter portion toward the first pipe; The insertion portion is divided into an insertion allowance portion and a contact portion that contacts the enlarged diameter portion. a step of abutting the two components in such a manner as described above; 2 a step of attaching a reaction member to the pipe; a step of attaching a joint member to the fixing portion; and a step of operating the joint member to fix the pipe. 1 and inserting the pipe into the inner diameter portion.

[0015] In the bonding method according to the present invention,1 After inserting the tube into the inner diameter portion, It is preferable to include a step of removing the arm portion.

[0016] In the bonding method according to the present invention, 1 After inserting the tube into the inner diameter portion, It is preferable to include a step of removing the joining member.

[0017] In the bonding method according to the present invention, 1 After inserting the tube into the inner diameter portion, It is preferable to include a step of removing the reaction member.

[0018] A joining member according to the present invention is used to join a first pipe to a second pipe, the second pipe having an inner diameter portion into which the first pipe is inserted and an expanded diameter portion formed to be larger than the outer diameter of the inserted portion of the first pipe, the joining member comprising: a fixing portion fixed to the first pipe; a centering member having an arm portion that protrudes from the fixed portion toward the second pipe and is detachably attached to the enlarged diameter portion so as to be able to abut against the enlarged diameter portion; a reaction member attached to the second tube; An engaging claw that can be engaged with the fixed portion The device is characterized by comprising a connecting portion connected by a connecting means, and a winding portion that operates the connecting portion to wind up the connecting means.

[0019] In the joining member according to the present invention, it is preferable that the winding portion includes an operating portion that can be operated by an electric tool.

[0020] The above summary of the invention does not list all of the necessary features of the present invention, and subcombinations of these features may also constitute inventions. [Effects of the Invention]

[0021] The joining method of the present invention is a method for joining a first pipe to a second pipe, the first pipe being inserted into an inner diameter portion and having an expanded diameter portion formed larger than the outer diameter of the inserted portion of the first pipe, and includes the steps of: fixing a fixed portion to the first pipe; attaching an arm portion to the fixed portion that protrudes toward the second pipe; abutting an abutment portion formed on the arm portion against the expanded diameter portion so that the abutment portion protrudes from the end of the expanded diameter portion in the direction of the second pipe; attaching a reaction member to the first pipe; attaching a joining member to the fixed portion; and operating the joining member to insert the second pipe into the inner diameter portion, thereby making it possible to maintain a centered state and shortening the work time in the excavation trench regardless of the worker's level of skill.

[0022] In addition, the joining member of the present invention is a joining member used to join a first pipe to a second pipe, into whose inner diameter portion the first pipe is inserted and which has an expanded diameter portion formed larger than the outer diameter of the inserted portion of the first pipe, and is equipped with a fixing portion fixed to the first pipe, an engageable engaging claw, a connecting portion connected to a reaction member attached to the second pipe by a connecting means, and a winding portion that operates the connecting portion to wind up the connecting means, thereby making it possible to shorten the work time in the excavation trench regardless of the skill level of the worker. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a perspective view showing an overview of a new pipe used in an open-cut construction method. [Figure 2] FIG. 2 is a perspective view of a centering member used in the joining method according to the first embodiment of the present invention. [Figure 3] 1 is a perspective view of a fixing portion of a centering member used in a joining method according to a first embodiment of the present invention. [Figure 4] 1 is a perspective view of an arm portion of a centering member used in a joining method according to a first embodiment of the present invention. [Figure 5] FIG. 2 is a side view of a centering member used in the joining method according to the first embodiment of the present invention. [Figure 6]1A and 1B are diagrams showing a reaction member used together with a centering member used in a joining method according to a first embodiment of the present invention, in which FIG. 1A shows an attached state and FIG. 1B shows a state in which the divided pieces are opened. [Figure 7] 1 is a perspective view of a joining member according to a first embodiment of the present invention. [Figure 8] FIG. 2( a ) is a perspective view illustrating a joining member according to a first embodiment of the present invention, and FIG. 2( b ) is a perspective view illustrating a modified example of a joining member used in the joining method according to the first embodiment of the present invention. [Figure 9] FIG. 1 is a flow diagram of a bonding method according to a first embodiment of the present invention. [Figure 10] FIG. 10 is a perspective view of an arm portion of a centering member used in a joining method according to a second embodiment of the present invention. [Figure 11] FIG. 10 is a perspective view of a fixing portion of a centering member used in a joining method according to a second embodiment of the present invention. [Figure 12] FIG. 10 is a perspective view showing a modified example of the fixing portion of the centering member used in the joining method according to the second embodiment of the present invention. [Figure 13] FIG. 10 is a perspective view of a reaction member used together with a centering member used in a joining method according to a second embodiment of the present invention. [Figure 14] FIG. 10 is a perspective view of a centering member and a reaction member used in a joining method according to a second embodiment of the present invention. [Figure 15] FIG. 6 is a perspective view of a joining member according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Preferred embodiments for carrying out the present invention will be described below with reference to the drawings. Note that the following embodiments do not limit the inventions according to the claims, and not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0025] [First embodiment] FIG. 1 is a perspective view showing an overview of a newly installed pipe used in an open cut method, FIG. 2 is a perspective view of a centering member used in a joining method according to a first embodiment of the present invention, FIG. 3 is a perspective view of a fixing portion of the centering member used in a joining method according to a first embodiment of the present invention, FIG. 4 is a perspective view of an arm portion of the centering member used in a joining method according to a first embodiment of the present invention, FIG. 5 is a side view of the centering member used in a joining method according to a first embodiment of the present invention, FIG. 6 is a reaction member used together with the centering member used in a joining method according to a first embodiment of the present invention, where (a) is a diagram showing the installed state and (b) is a diagram showing the divided pieces in an open state, FIG. 7 is a perspective view of a joining member according to a first embodiment of the present invention, FIG. 8(a) is a perspective view explaining a joining member according to a first embodiment of the present invention, and (b) is a perspective view showing a modified example of a joining member used in a joining method according to a first embodiment of the present invention, and FIG. 9 is a flow chart of a joining method according to a first embodiment of the present invention.

[0026] As shown in FIG. 1, the new pipes (second pipe 1 and first pipe 2) to be laid using the joining method according to this embodiment are hollow iron pipe members having a predetermined length, and ductile iron pipes are suitable. The second tube 1 and the first tube 2 have an insertion section formed at the tip end to serve as an insertion port 4, a receiving port 3a formed at the base end, and an expanded diameter section 3 formed with an outer diameter larger than that of the insertion section.

[0027] The second pipe 1 and the first pipe 2 are joined together by fitting the insertion port 4 of the first pipe 2 into the socket 3a of the already laid second pipe 1. A sealing rubber ring and a lock ring to prevent slipping out (not shown) are provided between the socket 3a and the insertion port 4. When the insertion port 4 is inserted into the socket 3a, the sealing rubber ring tightly contacts the tip of the insertion port 4 with the socket 3a, leaving no gap. Note that a lubricant is applied to the outer periphery of the insertion port 4 and the inner periphery of the sealing rubber ring attached to the socket 3a of the second pipe 1 to prevent it from falling off or being damaged when the first pipe 2 is inserted.

[0028] When joining the insertion port 4 of the first pipe 2 to the receiving port 3a of the second pipe 1 that has already been laid in the excavation trench, the second pipe 1 and the first pipe 2 must be centered so that the center lines of the second pipe 1 and the first pipe 2 coincide.

[0029] 2, the centering member 10 used in the joining method according to this embodiment can be attached to the first pipe 2 to center the second pipe 1 and the first pipe 2. The centering member 10 according to this embodiment has a fixed part 11 attached to the insertion port 4 of the first pipe 2 and an arm part 12 detachably attached to the fixed part 11.

[0030] As shown in FIG. 3 , the fixing portion 11 is a band-shaped member that is wound around the outer periphery of the insertion port 4 of the first pipe 2 and attached. The fixing portion 11 is attached at a predetermined distance from the tip of the insertion port 4 so as not to overlap the portion of the insertion port 4 inserted into the socket 3a. The fixing portion 11 has a band body 25 and a pair of flanges 26, 26 formed to protrude radially from both ends of the band body 25 toward the first pipe 2, and is fixed by bolts and nuts 23 that connect the flanges 26, 26 to each other. The flanges 26 are spaced apart at a predetermined interval, and the shanks 23a of the bolts and nuts 23 are positioned across the interval so that the detachable portion 20, described below, can engage with and be fixed. The flange 26 also has a joining member attachment portion 24 that protrudes longitudinally and to which a joining member 30, described below, is attached.

[0031] As shown in Fig. 2, the arm portion 12 is attached to the fixed portion 11 and extends so as to protrude from the fixed portion 11 in the direction of the second pipe 1. As shown in Fig. 4, the arm portion 12 has a detachable portion 20 formed on the base end side, and the detachable portion 20 is attached to the fixed portion 11. The arm portion 12 also has a pair of arms 16, 16 extending approximately parallel to each other in the longitudinal direction from the detachable portion 20, and abutment portions 13 formed on the tip sides of the pair of arms 16, 16. The pair of arms 16 are curved so as to be convex upward to ensure that the abutment portion 13, which will be described later, and the expanded diameter portion 3 abut against each other.

[0032] The detachable part 20 has an engaging part 21 that engages with the shank 23a of the bolt 23 of the fixed part 11, and a claw part 22 that holds the shank 23a engaged with the engaging part 21. The claw part 22 is biased against the shank 23a by a spring (not shown) so that it can be freely engaged with and disengaged from the shank 23a, and is configured to prevent the arm part 12 from accidentally coming off when the abutting part 13 is brought into abutment with the enlarged diameter part 3 to center the first pipe 2 and the second pipe 1, and also to allow the arm part 12 to be removed after the first pipe 2 is joined.

[0033] The pair of arms 16, 16 are arranged with a predetermined gap S between them, and their tip ends are connected to each other by a reinforcing part 17. If necessary, a reinforcing part may also be provided in the middle part of the arm 16. At the tip of the arm 16, there are provided reinforcing parts 17 spaced apart from each other. In this way, the contact portions 13 extend in directions away from each other, and therefore the contact portions 13 come into contact with the enlarged diameter portion 3 at two points, allowing for more accurate centering of the second pipe 1 and the first pipe 2.

[0034] 5, when the abutment portion 13 abuts against the enlarged diameter portion 3 while the end of the socket 3a of the second pipe 1 and the tip of the insertion port 4 of the first pipe 2 are aligned, the abutment portion 13 has an abutment portion 14 that abuts against the enlarged diameter portion 3 and an insertion margin portion 15 that is positioned protruding from the base end of the enlarged diameter portion 3. A sealing rubber ring (not shown) is set inside the socket 3a, and is set at a position that is a certain distance away from the end of the socket 3a toward the other end in the pipe axial direction. At this time, the centering state must be maintained until the insertion port 4 of the first tube 2 is inserted into the sealing rubber ring, but by having this insertion allowance portion 15, when the first tube 2 is inserted into the second tube 1, the abutment portion 13 moves toward the tip along the longitudinal direction of the enlarged diameter portion 3, and the insertion allowance portion 15 securely abuts against the enlarged diameter portion 3 until it is inserted into the sealing rubber ring.Even if the first tube 2 is inserted to a position where the abutment portion 14 does not abut against the enlarged diameter portion 3, the abutment portion 13 is prevented from falling off the enlarged diameter portion 3, and reliable centering can be maintained.

[0035] Next, a joining member 30 according to this embodiment will be described with reference to Figures 6 to 8. As shown in Figures 7 and 8(a), the joining member 30 has an engaging claw 31 that engages with the joining member mounting portion 24 of the fixed portion 11, and is formed so as to be attachable to the fixed portion 11. At this time, the joining member 30 is sandwiched in the gap S between the pair of arm portions 16, 16, and is thereby restrained in the lateral direction. The joining member 30 also has, as a connecting portion, a worm gear 32 and a gear 33 that meshes with the worm gear 32. The worm gear 32 is arranged so as to be rotatable by operating an operating portion 32a, and the gear 33 has a winding portion 34 that can wind up a wire 41, which will be described later.

[0036] The operation unit 32a is preferably provided with a power tool such as an impact driver to rotate the worm gear 32. In addition to the power tool, a handle or the like that manually applies a rotational force may also be attached.

[0037] 8(b), a connecting device 30' having a conventionally known ratchet structure may be used without attaching the connecting member 30. In this case, a hook-equipped metal fitting 50 having a hook 53 is attached to the fixing part 11, and the reaction member 40 and the hook 53 can be connected and fastened together using the connecting device 30'.

[0038] The hook fitting 50 has an engagement pin 52 that engages with the claw portion 22 of the fixed portion 11, and an engagement groove 51 that engages with the mounting pin 11a of the arm portion 12. The engagement groove 51 has a groove portion and a notch portion that extend in the pipe axial direction. The hook fitting 50 is attached so as to fit onto the arm portion 12.

[0039] In addition, a reaction member 40 is attached to the second pipe 1 at a position that does not overlap with the enlarged diameter portion 3. The reaction member 40 is a jig for taking up the reaction force during joining, and has a ring-shaped portion 42 to which a hook portion 41a of a wire 41 serving as a connecting means is attached. The joining member 30 and the reaction member 40 are connected by the wire 41, and the first pipe 2 is joined to the second pipe 1 by winding up the wire 41 around the winding portion 34 of the joining member 30. The wire 41 may be a chain 41' as shown in FIG. 8(b).

[0040] As shown in Fig. 6(a), the reaction member 40 is configured by fastening a pair of divided pieces 43a, 43b attached to the outer periphery of the second pipe 1 together with a hinge 44. As shown in Fig. 6(b), the first divided piece 43a has an upper piece 45a and a pair of side pieces hanging down from both ends of the upper piece 45a. The first divided piece 43a is a generally C-shaped member that opens downward and has upper and lower pieces 45b, 45b, and the second divided piece 43b is a generally C-shaped member that opens laterally and has a pair of upper and lower pieces 46a, 46a and a side piece 46b connecting one end of the pair of upper and lower pieces 46a, 46a. The first divided piece 43a and the second divided piece 43b are rotatably connected by a hinge 44, with one side piece 45b of the first divided piece 43a and the side piece 46b of the second divided piece 43b. In addition, the annular portion 42 is attached to the upper piece 46a of the second divided piece 43b.

[0041] Because the reaction member 40 is configured in this manner, when attaching the reaction member 40 to the second pipe 1, as shown in Figure 6(b), the segments are opened to an angle of approximately 90°, and the opening of the first segment 43a is inserted so that it contacts the outer periphery of the second pipe 1. At this time, the second segment 43b is arranged along the longitudinal direction of the second pipe 1, so it does not interfere with the second pipe 1 when assembling the first segment 43a.

[0042] Then, the hinge 44 is rotated to move the second segment 43b so that it is approximately parallel to the first segment 43a, as shown in Figure 6(a). At this time, because the second segment 43b has an opening in the horizontal direction, the opening of the second segment 43b moves along the outer periphery of the second pipe 1, preventing interference between the second segment 43b and the outer periphery of the second pipe 1. When the second segment 43b moves to the state shown in Figure 5(a), the lower piece 46a of the second segment 43b closes the opening of the first segment 43a (the lower portion of the second pipe 1), making it possible to attach the reaction member 40 to the outer periphery of the second pipe 1.

[0043] Furthermore, the reaction member 40 can be easily removed by opening the second segment 43b to the position shown in Figure 6(b), so it is configured to be easily removed from the second pipe 1 after the first pipe 2 is joined.

[0044] Next, a method for joining the second pipe 1 and the first pipe 2 according to this embodiment will be described with reference to Fig. 9. First, the fixing part 11 is attached to and fixed to the first pipe 2 (S101). The fixing part 11 may be attached at the site where the new pipe is laid, or may be attached at a factory when the new pipe (first pipe 2) is manufactured.

[0045] Thereafter, the arm portion 12 is attached to the fixed portion 11 (S102). Specifically, the shaft portion 23a of the fixed portion 11 is engaged with the engaging portion 21 of the detachable portion 20 of the arm portion 12, and the shaft portion 23a is fixed by the claw portion 22. At this time, the claw portion 22 is biased toward the shaft portion 23a by a spring (not shown), so the shaft portion 23a can be engaged with the engaging portion 21 by retracting the claw portion 22 against the spring force in the direction opposite to the biasing side toward the shaft portion 23a.

[0046] Next, a lubricant is applied to the outer periphery of the insertion port 4 of the first pipe 2 to which the arm portion 12 is attached and to the inner periphery of a sealing rubber ring (not shown) set in the socket 3a of the already laid second pipe 1. Then, the first pipe 2 is lowered into the excavated trench using a crane or the like, and the abutting portion 13 of the arm portion 12 is brought into abutment with the expanded diameter portion 3 of the second pipe 1 laid in the excavated trench. At this time, the abutting portion 13 is positioned so that it has an insertion allowance portion 15 that extends from the base end of the expanded diameter portion 3 toward the first pipe 2. This abutment between the expanded diameter portion 3 and the abutting portion 13 allows the second pipe 1 and the first pipe 2 to be centered.

[0047] Next, the reaction member 40 is attached to the second pipe 1 at a position where it does not overlap with the enlarged diameter portion 3 (S104). The attachment of this reaction member 40 may be performed before the step of bringing the contact portion 13 into contact with the enlarged diameter portion 3 (S103).

[0048] Next, the joining member 30 is attached to the second pipe 1 and the first pipe 2 (S105). Specifically, the engaging claws 31 of the joining member 30 are engaged with the fixing portion 11 of the first pipe 2, and the pair of arm portions 16 are The joining member 30 is held between them. The hook portion 41a of the wire 41 is attached to the annular portion 42 of the reaction member 40.

[0049] Next, the operating portion 32a of the joining member 30 is rotated with a power tool or the like to wind up the wire 41, whereby the reaction member 40 engages with the step with the enlarged diameter portion 3, and the reaction force causes the first pipe 2 to be inserted into the socket 3a of the second pipe 1 and fitted together (S106). At this time, instead of using the joining member 30, a joining device having a conventionally known ratchet structure as shown in Figure 8(b) may be used.

[0050] After the fitting of the first pipe 2 is completed, the arm portion 12, the joining member 30, and the reaction member 40 are removed (S107 to S109). The order in which the arm portion 12, the joining member 30, and the reaction member 40 are removed is not limited to the order shown in Fig. 9, and any order is acceptable. The fixing portion 11 may also be removed at the same time, but may also be buried while still attached to the first pipe 2.

[0051] After that, the joint status of the second pipe 1 and the first pipe 2 is checked using a check gauge or the like, and then the first pipe 2 becomes the second pipe that has already been laid, and the joining work of the next first pipe is carried out.The process is repeated until the required length of the new pipe is obtained, thereby completing the laying of the new pipe.

[0052] As described above, with the joining method and joining member according to this embodiment, the second pipe 1 and the first pipe 2 can be centered simply by bringing the abutting portion 13 into contact with the enlarged diameter portion 3, which makes it easy to perform the centering and positioning work and reduces the work time in the excavated trench regardless of the skill level of the worker. Also, the second pipe 1 and the first pipe 2 can be easily joined simply by operating the operating portion of the joining member 30 with a power tool or the like.

[0053] [Second embodiment] The centering member used in the joining method according to the first embodiment described above has an arm portion and a fixed portion, and has been described as being joined by a joining member using a reaction member. The centering member used in the joining method according to the second embodiment, which will be described next, will have an arm portion, a fixed portion, and a reaction member that have different configurations from those in the first embodiment. Note that components that are the same as or similar to those in the first embodiment described above will be assigned the same reference numerals, and detailed descriptions thereof will be omitted.

[0054] Figure 10 is an oblique view of the arm portion of a centering member used in a joining method according to a second embodiment of the present invention, Figure 11 is an oblique view of the fixing portion of a centering member used in a joining method according to a second embodiment of the present invention, Figure 12 is an oblique view showing a modified example of the fixing portion of a centering member used in a joining method according to a second embodiment of the present invention, Figure 13 is an oblique view of a reaction member used together with a centering member used in a joining method according to a second embodiment of the present invention, Figure 14 is an oblique view of a reaction member used together with a centering member used in a joining method according to a second embodiment of the present invention, and Figure 15 is an oblique view of a joining member according to a second embodiment of the present invention.

[0055] 10, the arm portion 62 used in the joining method according to this embodiment has a detachable portion 20 formed on its base end. The arm portion 62 also has a pair of arms 16, 16 extending substantially parallel to each other along the longitudinal direction from the detachable portion 20, and abutment portions 13 formed on the tip ends of the pair of arms 16, 16. Similar to the centering member used in the joining method according to the first embodiment, the pair of arms 16 are curved so as to be convex upward to ensure that the abutment portions 13 and the enlarged diameter portion 3 abut securely.

[0056] The pair of arms 16, 16 are arranged with a predetermined gap S between them, and their tip ends are connected to each other by a reinforcing portion 17. Furthermore, a reinforcing portion may also be provided in the middle portion of the arm 16, if necessary. Abutment flanges 63 are formed at the tip of the arm 16, extending in directions away from each of the pair of arms 16. Furthermore, abutment flanges 63 are attached to blade members 64 that abut against the enlarged diameter portion 3, and blade members 64 are attached to adjustment screws 65 as adjustment means attached to the reinforcing portion 17, and are attached so as to be movable toward and away from the enlarged diameter portion 3.

[0057] The blade member 64 includes a blade member main body 64a that corresponds to the abutment flange 63, and a connecting portion 64b into which an adjustment screw 65 is threaded. The blade member main body 64a is attached to the abutment flange 63 by a bolt and nut 64c that is inserted into the abutment flange 63 so that it does not come off the abutment flange 63. In this way, the abutment portion 13 has blade members 64 that can move toward or away from the enlarged diameter portion 3, and adjustment means 65, so that it can accommodate pipes of various sizes, even if the sizes of the second pipe 1 and the first pipe 2 are different.

[0058] Furthermore, a handle 66 is formed on the distal end side of the arm 62, extending from each of the pair of arms 16 in a direction away from each other. The handle 66 also connects the pair of arms 16, 16 on the distal end side of the arm 62. By providing such a handle 66, it is possible to safely guide and center the tube.

[0059] 11, the fixing part 61 is formed by combining a pair of fixing part segments 61a, 61a. The fixing part segment 61a has a fixing part segment main body 61b curved to correspond to the outer periphery of the insertion port 4 of the first pipe 2, and a first flange 67 and a second flange 68 formed on both ends of the fixing part segment main body 61b.

[0060] The first flange 67 and the second flange 68 are formed to protrude radially, and are formed with bolt holes 71 through which bolts and nuts that fasten the fixing portion segments 61a together are inserted. The second flange 68 is formed with a pin 69 that protrudes toward the other fixing portion segment 61a, and the first flange 67 is formed with a pin hole 70 at a position corresponding to the pin 69, into which the pin 69 can be inserted. Note that the detailed shapes of the first flange 67 and the second flange 68 are similar to those of the flange 26 formed on the fixing portion 11 of the centering member 10 used in the joining method according to the first embodiment described above, and therefore detailed description thereof will be omitted.

[0061] In this way, the fixing part 61 used in the joining method according to this embodiment can be attached to the insertion port 4 of the first pipe 2 by inserting the pin portion 69 of one fixing part segment 61a into the pin hole 70 of the other fixing part segment 61a to fix their positions relative to each other, and then inserting a bolt (not shown) through the bolt hole 71 and fastening with a nut. Furthermore, because the fixing part 61 used in the joining method according to this embodiment can be separated in the radial direction of the first pipe 2, attachment and removal operations can be performed in a space-saving manner.

[0062] Furthermore, the fixing part 61 used in the joining method according to this embodiment has a pair of flanges 72 formed by combining a first flange 67 and a second flange 68, one above the other in Fig. 11. In this way, by forming flanges 72 on the top and bottom that can engage and fix the detachable part 20 of the arm part 62, it is possible to join the socket of a new pipe to the insertion port of an already laid pipe by attaching the arm part 62 to the lower flange 72, as shown in Fig. 15.

[0063] The fixing portion 61 used in the joining method according to this embodiment may be a completely separate type in which fixing portion segments 61a are fixed with bolts and nuts as described above, but as a modified example, as shown in Fig. 12, a pair of fixing portion segments 61c may be rotatably assembled with a ball joint 73, and a hinge portion 74 attached to one fixing portion segment 61c may be engaged with a hinge locking portion 75 attached to the other fixing portion segment 61c to fix them together as a fixing portion 61'. In this case, by fixing the hinge portion 74 and the hinge locking portion 75 with a fixing bolt 76 attached to the hinge portion 74, the fixation between the hinge portion 74 and the hinge locking portion 75 is prevented from being released.

[0064] Furthermore, the fixing portion 61' used in the joining method according to this modified example has a pair of flange portions 72 formed on the top and bottom, similar to the fixing portion 61 described above, but the flange portions 72 are formed approximately in the center of the fixing portion segment 61c, and it is preferable that the flange portions 72, hinge portion 74, flange portion 72 and hinge locking portion 75 are arranged at approximately equal intervals in the circumferential direction.

[0065] As shown in Figures 13 and 14, the reaction member 80 is made up of a first reaction member piece 81 formed in an approximately U-shape and a second reaction member piece 82 formed in an approximately U-shape, which are attached via a hinge 83 so as to be able to open and close freely.

[0066] 13, the first reaction member piece 81 is disposed so as to open downward, and has a first reaction member piece main body 81a, and a first side leg 81b and a second side leg 81c extending downward from both ends of the first reaction member piece main body 81a. An elongated guide hole 88a and a first gripping portion 87 extending in a direction generally perpendicular to the extending direction of the first side leg 81b and the second side leg 81c are formed in the approximate center of the first reaction member piece main body 81a.

[0067] 14, the second reaction member piece 82 is arranged so as to open to the side, and has a second reaction member piece main body 82a, and an upper leg portion 82b and a lower leg portion 82c extending perpendicularly from both ends of the second reaction member piece main body 82a. The lower leg portion 82c is formed with a second grip portion 89 that faces the first grip portion 87 described above.

[0068] A support base 86 is formed at the approximate center of the upper leg 82b, extending in a direction approximately perpendicular to the extending direction of the upper leg 82b and the lower leg 82c. A hook receiving member 84 that pivots via a pivot 84a is attached to the support base 86, and the hook receiving member 84 is biased by an elastic body 85 in the circumferential direction of the pivot 84a.

[0069] 13, the hook receiving member 84 is biased around the pivot 84a by an elastic body 85, and abuts against the upper end of the first reaction member piece main body 81a, biasing the second reaction member piece 82 upward. The second reaction member piece 82 is guided in the vertical direction by a guide pin 88 formed on the upper leg portion 82b of the second reaction member piece 82 and an elongated guide hole 88a formed in the first reaction member piece main body 81a.

[0070] The first lateral leg 81b of the first reaction member piece 81 and the second reaction member piece main body 82a of the second reaction member piece 82 are attached so as to be able to open and close freely via a hinge 83, but the hinge 83 has enough play to allow the second reaction member piece 82 to move vertically by the hook receiving member 84.

[0071] In this way, the second reaction member piece 82 of the reaction member 80 is biased downward and upward by the hook receiving member 84, so that the first gripping portion 87 and the second gripping portion 89 come close to each other and clamp the outer periphery of the first tube 2, thereby preventing the reaction member 80 from shifting.

[0072] Next, with reference to FIG. 15 , a method for joining a centering member 10′ used in the joining method according to this embodiment will be described. As shown in FIG. 15 , a fixed portion 61 is attached to the insertion opening 4 of the second pipe 1, which is a buried pipe. An arm portion 62 is attached to the lower portion 72. At this time, the arm portion 62 is attached upside down with the abutment portion 13 facing upward, compared to the centering member 10 used in the joining method according to the first embodiment. The positions of the blade members 64 are adjusted as necessary to fine-tune the positions of the second pipe 1 and the first pipe 2. Furthermore, a joining member 30 is attached to the flange portion 72 above the fixed portion 61. The method for attaching the arm portion 62 and joining member 30 is similar to that of the centering member 10 used in the joining method according to the first embodiment, and therefore a detailed description thereof will be omitted.

[0073] The reaction member 80 is attached at a position that does not overlap the enlarged diameter portion 3 of the first pipe 2, and a hook portion 41a formed at the tip of a chain 41' extending from the joining member 30 is engaged with the hook receiving member 84. The joining member 30 is then operated to wind up the chain 41', and the receiving opening 3a of the first pipe 2 is inserted into the insertion opening 4 of the second pipe 1, joining the first pipe 2 and the second pipe 1. Furthermore, as the chain 41' is wound up, the hook receiving member 84 pivots about the pivot 84a, so that the reaction member 80 is more firmly fixed to the outer periphery of the first pipe 2.

[0074] In this way, the centering member 10' used in the joining method of this embodiment makes it easy to attach and detach the fixing portion 61, so that the fixing portion 61 can be used repeatedly without being buried, thereby reducing costs.

[0075] In the above first embodiment, the joining member 30 is described as being composed of a gear 33 and a worm gear 32, but it is also possible to provide multiple gears 33, or to eliminate the worm gear 32 and directly operate the gear 33.

[0076] Furthermore, the centering member according to the first embodiment has been described as being used to join the insertion end 4 of the first pipe 2 to the socket 3a of the second pipe 1 that has already been laid. However, as with the centering member used in the joining method according to the second embodiment, it may also be used to join the insertion end of a new pipe to the insertion end of an already laid pipe. In this case, the arm 12 is attached to the already laid pipe with the abutment portion 13 facing upward, and the enlarged diameter portion of a pipe suspended by a crane or the like is abutted against the arm 12, thereby enabling centering of the pipes. Furthermore, as a modified example of the fixing member used in the joining method according to the second embodiment, the fixing member 61′ in which a pair of fixing portion segments 61c are rotatably assembled with a ball joint 73 has been described. However, the pair of fixing portion segments 61c may also be rotatably assembled with a universal joint. It is clear from the claims that such modifications and improvements are also within the technical scope of the present invention. [Explanation of symbols]

[0077] 1 Second tube 2. First tube 3 Expanded diameter part 3a Socket (inner diameter) 4 Insertion port (insertion part) 10,10´ Centering element 11,61 Fixed part 12,62 Arm section 13 Contact part 14 Contact part 15 Insertion margin 16 Arm 17 Reinforcement 20 Detachable part 21 Engagement portion 22 Claw 23 volts 23a Shaft 24 Joint member attachment part 25 Band body 26,72 Tsuba section 30 Joint material 31 Engagement claw 32 worm gear 32a Operation section 33 Gears 34 Winding section 40,80 Reaction member 41 Wire 41´ Chain 41a Hook part 42 Annular section 43a First piece 43b Second piece 44 Hinge 50 Hooked metal fittings 51 Engagement groove 52 Engagement pin 53 Hook 61a Fixed segment 61b Fixed part body 63 Contact part flange 64 Wing member 64a Blade member body 64b Connection part 64c bolts and nuts 65 Adjustment screw (adjustment means) 66 Handle 67 First flange 68 Second flange 69 Pin section 70 pin holes 71 Bolt holes 73 Ball Joint 74 Hinge part 75 Hinge locking part 81 First reaction member piece 82 Second reaction member piece 83 Hinge 84 Hook receiving member 84a Axis 85 Elastic Body 86 Support stand 87 First gripping part 88 Guide Pin 89 Second gripping part S void

Claims

1. A method for joining a first pipe to a second pipe, the second pipe having an inner diameter portion into which the first pipe is inserted and an expanded diameter portion formed to be larger than an outer diameter of the inserted portion of the first pipe, comprising: Fixing a fixture to the first tube; attaching an arm portion to the fixing portion, the arm portion protruding in a direction toward the second pipe; a step of abutting a contact portion formed at the tip of the arm portion against the enlarged diameter portion in a manner that divides the enlarged diameter portion into an insertion allowance portion where the contact portion protrudes from the end of the enlarged diameter portion toward the first tube, and an abutment portion that abuts against the enlarged diameter portion when the tip of the insertion portion of the first tube is positioned at the end of the enlarged diameter portion of the second tube; attaching a reaction member to the second tube; attaching a joining member to the fixing portion; manipulating the joining member to insert a first tube into the inner diameter portion; A joining method comprising:

2. The joining method according to claim 1, a step of inserting the first pipe into the inner diameter portion and then removing the arm portion.

3. The joining method according to claim 1 or 2, a step of removing the joining member after inserting the first pipe into the inner diameter portion.

4. The joining method according to any one of claims 1 to 3, a step of removing the reaction member after inserting the first pipe into the inner diameter portion.

5. A joining member used to join a first pipe and a second pipe, the second pipe having an inner diameter portion into which the first pipe is inserted and an expanded diameter portion formed to be larger than the outer diameter of the inserted portion of the first pipe, a centering member having a fixing portion fixed to the first pipe and an arm portion protruding from the fixing portion toward the second pipe and removably attached to the expanded diameter portion so as to be able to abut against the expanded diameter portion; a connecting portion connected to the reaction member attached to the second pipe by a connecting means having an engaging claw that can be engaged with the fixed portion; a winding section that operates the connecting section to wind up the connecting means.

6. The joining member according to claim 5, The joining member is characterized in that the winding portion has an operating portion that can be operated by an electric tool.

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