Bending angle measurement method and bending angle measurement simulation pipe for pipe joint

Abstract

To provide a bending angle measurement method and a bending angle measurement simulation pile for a pipe joint, which can easily and accurately set a zero point of a bending angle of the pipe joint.SOLUTION: The bending angle measurement method has the steps of: installing angle measurement means inside pipe bodies 2, 3; attaching an abutment member 4 having a pipe axial end included in a plane in which a pipe axis of one pipe body 2 is a surface normal line to an outer periphery of an insertion port; inserting the insertion port into a socket until contact of the pipe axial end of the abutment member 4 attached to the outer periphery of the insertion port with an end of the socket; and setting a zero point of the angle measurement means in a state where the pipe axial end of the abutment member 4 is in contact with the end of the socket. A bending angle measurement simulation pipe 1 has one pipe body 2 in which the insertion port is formed, the other pipe body 3 in which the socket for inserting the insertion port is formed, and the abutment member 4 having the pipe axial end included in the plane in which the pipe axis of one pipe body 2 is the surface normal line.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for measuring the bending angle of a pipe joint, and a dummy pipe for measuring the bending angle of a pipe joint. [Background technology]

[0002] In the pipe-in-pipe method, in which a new ductile iron pipe (such as a PN or PII type pipe) is inserted into an existing pipe that serves as a sheath to create a new pipeline inside a deteriorated existing pipe, a preliminary survey is sometimes conducted before the actual construction to confirm whether the new pipe can be inserted smoothly.One method of this preliminary survey is to join two mock pipes that simulate the new pipes that will actually be inserted, and then pull these joined mock pipes into the existing pipe using a wire pulled by a winch, and then measure the bending angle of the joints of these mock pipes to check whether the mock pipes can pass smoothly from the starting shaft to the arrival shaft.

[0003] For example, Patent Document 1 below shows a method of calculating the bending angle of a joint by arranging displacement gauges at four locations at 90-degree intervals in the circumferential direction, while Patent Document 2 below shows a method of calculating the angle of a joint by arranging two displacement gauges in the vertical and horizontal directions, or three at the vertices of a triangle.

[0004] When measuring the bending angle of a pipe joint, first, two mock pipes are brought into the starting shaft and the joint is joined. At this time, the distance between the white line (approximately 10 mm wide) marked on the insertion port of one pipe and the end face of the receiving port of the other pipe is equal at the four equal points on the top, bottom, left and right circumference of the pipe joint, so that one pipe body and the other pipe body are joined straight in the pipe joint, and in this state the zero point of the angle measuring means installed on the pipes is generally set. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5174361 [Patent Document 2] Japanese Patent Publication No. 2022-152238 Summary of the Invention [Problem to be solved by the invention]

[0006] When setting the zero point as described above, the dimensions of the insertion port into the receiving port differ by several millimeters above and below and to the left and right of the pipe fitting, which causes the true zero point of the bending angle of the pipe fitting to differ from the zero point of the pipe fitting of the simulated pipe during the survey, resulting in an error in the measured bending angle.

[0007] SUMMARY OF THE INVENTION It is therefore an object of the present invention to easily and accurately set the zero point of the bending angle of a pipe joint. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides: A method for measuring a bending angle of a pipe joint, which is constructed by inserting an insertion port of one pipe body into a receiving port of another pipe body, by using an angle measuring means provided on the pipe body, a step of installing the angle measurement means inside the tubular body; a step of attaching an abutment member having an end portion in the tube axis direction included in a plane having the tube axis of the one tube body as a surface normal to the outer periphery of the insertion port; a step of inserting the insertion port into the receiving port until the end of the abutting member attached to the outer periphery of the insertion port in the pipe axis direction abuts against an end of the receiving port; a step of setting a zero point of the angle measuring means in a state in which the end of the abutting member in the pipe axis direction and the end of the socket are in contact with each other; A method for measuring the bending angle of a pipe joint was constructed (first configuration).

[0009] In this way, the zero point of the bending angle of the pipe joint can be set easily and accurately by the abutment between the pipe axial direction end of the abutting member and the end of the socket.

[0010] In the first configuration, The abutment member is an annular member having an inner surface that conforms to the outer periphery of one of the pipe bodies and extending in a band-like shape along the circumferential direction with the same width in the pipe axial direction, and the annular member can be constructed by circumferentially connecting multiple divided annular bodies that are divided circumferentially (second configuration).

[0011] In this way, the inner surface of the annular member abuts against the outer periphery of one of the pipe bodies, making it easy to align the axis of the annular member in the pipe axis direction, and making it easy to attach and detach the annular member to the outer periphery of one of the pipe bodies.

[0012] In the second configuration, A circumferential groove is formed on the outer periphery of the insertion port, and protrusions extending radially inward are formed on the inner surfaces of the multiple divided annular bodies, and by engaging the protrusions with the circumferential groove, the positions of the multiple divided annular bodies in the pipe axis direction can be aligned (third configuration).

[0013] In this way, the annular member can be smoothly constructed from a plurality of divided annular bodies.

[0014] In any one of the first to third configurations, The fourth configuration may further include a step of attaching a reaction member to the other tube body, providing an intervening member so as to straddle the abutment member and the reaction member, and pulling the abutment member toward the reaction member via the intervening member.

[0015] In this way, the abutment state between the end of the abutting member in the pipe axial direction and the end of the socket is improved, and the zero point of the bending angle of the pipe joint can be set more accurately.

[0016] In order to solve the above problems, the present invention provides: In a mock pipe for measuring the bending angle of a pipe joint, which is used when measuring the bending angle of a pipe joint, one tubular body having an insertion port formed therein; another pipe body having a receiving port into which the insertion port is inserted; a contact member attached to the outer periphery of the insertion port and having an end portion in the tube axis direction included in a plane having the tube axis of the one tube body as a surface normal; A simulated pipe for measuring the bending angle of a pipe joint was constructed (fifth configuration).

[0017] In this way, the zero point of the bending angle of the pipe joint can be set easily and accurately by the abutment between the pipe axial direction end of the abutting member and the end of the socket.

[0018] In the fifth configuration, The abutment member is an annular member having an inner surface that conforms to the outer periphery of one of the pipe bodies and extending in a band-like shape along the circumferential direction with the same width in the pipe axial direction, and the annular member can be constructed by circumferentially connecting multiple divided annular bodies that are divided circumferentially (sixth configuration).

[0019] In this way, the inner surface of the annular member abuts against the outer periphery of one of the pipe bodies, making it easy to align the axis of the annular member in the pipe axis direction, and making it easy to attach and detach the annular member to the outer periphery of one of the pipe bodies.

[0020] In the sixth configuration, A circumferential groove is formed on the outer periphery of the insertion port, and protrusions extending radially inward are formed on the inner surfaces of the multiple divided annular bodies, and by engaging the protrusions with the circumferential groove, the positions of the multiple divided annular bodies in the pipe axis direction can be aligned (seventh configuration).

[0021] In this way, the annular member can be smoothly assembled from the plurality of divided annular bodies.

[0022] In any one of the fifth to seventh configurations, The abutting member may be formed with a receiving portion for receiving a force acting in the axial direction of the tube (eighth configuration).

[0023] In this way, the force acting through the receiving portion strengthens the abutment state between the pipe axial direction end of the abutment member and the end of the receiving port, making it possible to more accurately set the zero point of the bending angle of the pipe joint. [Effects of the Invention]

[0024] In the present invention, the method for measuring the bending angle of a pipe joint and the mock pipe for measuring the bending angle of a pipe joint are configured as described above, so that the zero point of the bending angle of the pipe joint can be set simply and accurately. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a cross-sectional view showing a first embodiment of a mock pipe for measuring the bending angle of a pipe joint according to the present invention. [Figure 2] 2 shows a divided annular body used in the simulated pipe for measuring the bending angle of the pipe joint shown in FIG. 1, (a) is a front view, and (b) is a side view. [Figure 3] FIG. 10 is a cross-sectional view showing one embodiment of the method for measuring the bending angle of a pipe joint according to the present invention, in which the other pipe body is lowered into the departure shaft and connected to a winch provided on the arrival shaft side. [Figure 4] Following on from Figure 3, this is a cross-sectional view of one pipe body being pulled into the existing pipe, and then lowered into the starting shaft. [Figure 5] Continuing from FIG. 4, this is a cross-sectional view of the state in which the insertion port of one pipe body is inserted into the socket of the other pipe body until the abutment member provided on one pipe body abuts against the end face of the socket of the other pipe body. [Figure 6] FIG. 10 is a cross-sectional view showing a second embodiment of a mock pipe for measuring the bending angle of a pipe joint according to the present invention. [Figure 7] Cross-sectional view of the main part of the mock pipe used to measure the bending angle of the pipe joint shown in Figure 6 [Figure 8] 7 shows a divided annular body used in the simulated pipe for measuring the bending angle of the pipe joint shown in FIG. 6, (a) is a front view, and (b) is a side view. [Figure 9] FIG. 10 is a front view showing a third embodiment of a mock pipe for measuring the bending angle of a pipe joint according to the present invention. [Figure 10]10 shows the divided annular body used in the simulated pipe for measuring the bending angle of the pipe joint shown in FIG. 9, where (a) is a front view, (b) is a side view, and (c) is a rear view. DETAILED DESCRIPTION OF THE INVENTION

[0026] A first embodiment of a pipe fitting bend angle measurement dummy pipe 1 (hereinafter referred to as dummy pipe 1) used in the pipe fitting bend angle measurement method according to the present invention will be described with reference to the drawings. The dummy pipe 1 is used in a preliminary survey conducted before actual construction to confirm whether a new pipe can be smoothly inserted in a pipe-in-pipe construction method in which a new ductile iron pipe (such as a PN-type pipe or a PII-type pipe) is inserted into an existing pipe P that serves as a sheath pipe to construct a new pipeline inside the deteriorated existing pipe P. As shown in Fig. 1, the dummy pipe 1 has one pipe body 2 formed with a spigot, the other pipe body 3 formed with a socket into which the spigot is inserted, and an abutment member 4 attached to the outer periphery of the spigot and having an end portion in the pipe axis direction that is included in a plane normal to the pipe axis of the one pipe body 2.

[0027] A displacement gauge holder 5 is provided inside the insertion port of one of the tubular bodies 2. The displacement gauge holder 5 is a U-shaped member having a cylindrical portion with an axis aligned with the axial direction of the one of the tubular bodies 2 and a pair of disk portions extending radially outward from both ends of the cylindrical portion in the axial direction and with a through-hole formed in the center. The pair of disk portions each have three through-holes formed in the circumferential direction: 0 degrees, 90 degrees, and 180 degrees (in this embodiment, at the top, one of the left and right sides, and the bottom). Displacement gauges 6 are inserted into these through-holes so as to be parallel to the axial direction of the one of the tubular bodies 2. A flange formed on the outer edge of the disk portions and extending along the axial direction of the one of the tubular bodies 2 has a bolt hole. When a bolt provided in the bolt hole is screwed into the inner surface of the one of the tubular bodies 2, the displacement gauge holder 5 is fixed to the inner surface of the one of the tubular bodies 2. Note that the shape of the displacement gauge holder 5 is merely an example, and the shape is not limited to that described in the embodiment as long as it can reliably hold the displacement gauge 6.

[0028] The displacement meter 6 has a main body and a rod-shaped detection probe that protrudes from the main body. The detection probe is biased in one direction along its length (the direction in which it protrudes toward the target 7, which will be described later) by a biasing member (not shown). The detection probe is pushed into the main body against the biasing force of the biasing member, and the amount of displacement of the target 7 that abuts against the tip of the detection probe is detected from the amount of pushing. Each displacement meter 6 is connected to a data logger 9 via a switch box 8, and the measurement results are recorded in the data logger 9.

[0029] A target 7 is fixed inside the socket of the other tubular body 3. The target 7 is a member with a U-shaped cross section, which includes a cylindrical portion whose axis is along the axial direction of the other tubular body 3, and a pair of disk portions with a through hole formed in the center that extend radially outward from both ends of the cylindrical portion in the axial direction. The surfaces of the disk portions form a contact surface with the axial direction of the other tubular body 3 as the surface normal, and the tips of the detection probes of three displacement meters 6 provided on one tubular body 2 are configured to contact this contact surface.

[0030] The shape, number, installation direction, etc. of the displacement meter 6 and the shape of the target 7 are merely examples, and are not limited to those described in the embodiments as long as they can properly measure the bending angle between the two tubular bodies 2 and 3.

[0031] A sled member 10 having a tapered surface that narrows toward the tip is provided at the tip of the other pipe body 3 (the end opposite to the joint side with the one pipe body 2). By providing the sled member 10, when the simulation pipe 1 is moved inside the existing pipe P, the tip of the other pipe body 3 can be prevented from tilting downward and coming into contact with the inner bottom surface of the existing pipe P, and the simulation pipe 1 can be moved smoothly inside the existing pipe P.

[0032] The abutment member 4 is an annular member (hereinafter, designated by the same reference numeral as the abutment member 4) that has an inner surface that conforms to the outer periphery of one of the pipe bodies 2 and extends in a band-like shape along the circumferential direction with the same width in the pipe axial direction. In this embodiment, as shown in FIGS. 2(a) and 2(b), the annular member 4 is divided circumferentially into two divided annular bodies 4a. A flange extending radially outward is formed at the circumferential end of each divided annular body 4a, and a through-hole is formed in this flange. The two divided annular bodies 4a are integrated by butting the flanges formed on the divided annular bodies 4a together circumferentially and then inserting bolts into the through-holes and screwing them together with nuts. The number of divided annular bodies 4a in the circumferential direction can be changed as appropriate.

[0033] We will now explain the bending angle measurement method for a pipe joint using the above-mentioned simulated pipe 1. This bending angle measurement method is a method for measuring the bending angle of a pipe joint formed by inserting the insertion port of one pipe body 2 into the receiving port of the other pipe body 3 using angle measurement means provided on the pipe bodies 2 and 3. First, as shown in Figure 3, the other pipe body 3 (the pipe that will serve as the front pipe of the simulated pipe 1) is suspended above an insertion stand 11 provided inside a starting shaft H formed at one open end of an existing pipe P that will serve as a sheath pipe.

[0034] A towing fitting 12 with a hook attached to the front is provided inside the tip side of the other pipe body 3. A winch (not shown) is provided on the side of an arrival shaft (not shown) formed at the other open end of the existing pipe P, and this winch and the hook of the towing fitting 12 are connected by a towing wire 13. In addition, a water stop plug 14 is provided inside the other pipe body 3 to prevent foreign matter such as muddy water from flowing from the tip end to the rear end of the other pipe body 3.

[0035] Next, as shown in FIG. 4, the winch is operated to pull the other pipe body 3 slightly into the existing pipe P to secure space in the starting shaft H, and then the first pipe body 2 (the pipe that will serve as the rear pipe of the simulated pipe 1) is lowered into this space. Angle measurement means such as a displacement meter 6, a switch box 8, and a data logger 9 are installed inside the first pipe body 2, and a ring-shaped member 4 is attached to the outer periphery of the insertion port of the first pipe body 2. A water stop plug 15 is also installed inside the first pipe body 2 to prevent foreign matter such as muddy water from flowing from the rear end of the first pipe body 2 toward the front end. Furthermore, a towing fitting 16 is installed inside the rear end of the first pipe body 2 to connect a towing wire 13 connected to the winch.

[0036] Next, as shown in Figure 5, the winch is operated to pull one pipe 2 toward the other pipe 3, and the insertion port is inserted into the socket until the axial end of the annular member 4 attached to the outer periphery of the insertion port abuts the end of the socket of the other pipe 3 with no gaps around the entire circumference (metal-to-metal contact). This results in the axial direction of one pipe 2 being aligned with the axial direction of the other pipe 3, i.e., the two pipes 2 and 3 being joined straight. With the axial end of the annular member 4 abutting the end of the socket of the other pipe 3, the zero point of the angle measurement device (displacement meter 6, switch box 8, data logger 9) is set. After the zero point setting is complete, the annular member 4 attached to one pipe 2 is removed, and the winch is operated to pull the simulated pipe 1 into the existing pipe P, and measurement of the bending angle of the simulated pipe 1 begins.

[0037] The order of the steps in the bending angle measurement method described above may be changed. For example, the step of installing the angle measurement means and the step of attaching the annular member 4 to the outer periphery of the insertion port of one of the tubular bodies 2 may be performed in either order.

[0038] The method for measuring the bending angle of a pipe joint using the above-mentioned simulated pipe 1 brings the pipe axial end of the abutting member 4 into contact with the end of the receiving port of the other pipe body 3, thereby joining one pipe body 2 and the other pipe body 3 in a straight line, thereby making it possible to easily and accurately set the zero point for the bending angle of the pipe joint.

[0039] Furthermore, the method for measuring the bending angle of a pipe joint using the above-mentioned simulated pipe 1 uses, as the abutment member 4, a ring-shaped member 4 that has an inner surface that conforms to the outer periphery of one of the pipe bodies 2 and extends in a band-like shape circumferentially with the same width in the pipe axis direction, and this ring-shaped member 4 is constructed by connecting a plurality of divided ring-shaped members 4a that are divided circumferentially in the circumferential direction.Therefore, by abutting the inner surface of the ring-shaped member 4 with the outer periphery of one of the pipe bodies 2, the axis of the ring-shaped member 4 can be easily aligned in the pipe axis direction, and the ring-shaped member 4 can be easily attached and detached to the outer periphery of one of the pipe bodies 2.

[0040] A second embodiment of the mock pipe 1 used in the method for measuring the bending angle of a pipe joint according to the present invention will be described with reference to the drawings. As shown in Figures 6 and 7, the mock pipe 1 according to the second embodiment has the same basic configuration as the mock pipe 1 according to the first embodiment, but the shape of the annular member 4 serving as the abutment member 4 is different.

[0041] As shown in Figures 8(a) and 8(b), this annular member 4 has an inner surface that conforms to the outer periphery of one of the tubular bodies 2, and is shaped like a band extending circumferentially with the same width in the axial direction. In this embodiment, it is composed of two divided annular bodies 4a divided circumferentially. A protrusion 17 extending radially inward is formed on one side of the axial end of the inner surface of each divided annular body 4a. A circumferential groove 18 is formed on the outer periphery of the insertion opening of one of the tubular bodies 2. Each divided annular body 4a is attached to one of the tubular bodies 2 so that its protrusion 17 engages with the axial end of the circumferential groove 18 formed on the outer periphery of the insertion opening (see Figure 7).

[0042] The radial length of the protrusion 17 is shorter than the depth of the circumferential groove 18, and is configured so that when the protrusion 17 engages with the circumferential groove 18, the tip of the protrusion 17 does not come into contact with the bottom of the circumferential groove 18. In addition, the axial width of the protrusion 17 is shorter than the axial length of the circumferential groove 18 that is exposed on the pipe surface when the insertion length of the insertion port into the socket is minimized with one pipe body 2 and the other pipe body 3 joined together.

[0043] A flange extending radially outward is formed at the circumferential end of each divided annular body 4a, and a through hole is formed in this flange. The flanges formed on the two divided annular bodies 4a are butted together in the circumferential direction, and then the divided annular bodies 4a are integrated by inserting bolts into the through holes and screwing them with nuts.

[0044] In the simulated pipe 1 according to the second embodiment, the axial positions of the divided ring-shaped bodies 4a can be aligned simply by engaging the protrusions 17 formed on each divided ring-shaped body 4a with the circumferential grooves 18 formed on one of the pipe bodies 2, and therefore the annular member 4 can be smoothly assembled from the divided ring-shaped bodies 4a. Note that in this embodiment, the divided ring-shaped bodies 4a are configured so that the protrusions 17 are formed over the entire circumferential surface of the inner surface, but it is also possible to configure the divided ring-shaped bodies 4a so that there are some circumferential portions where the protrusions 17 are not formed.

[0045] A third embodiment of a dummy pipe 1 used in the method for measuring the bending angle of a pipe joint according to the present invention will be described with reference to the drawings. As shown in Figure 9, the dummy pipe 1 according to the third embodiment, like the first and second embodiments, has an annular member 4 attached to one pipe body 2, and a reaction member 19 of the same shape as the annular member 4 attached to the outer periphery (straight body portion) of the other pipe body 3 near the socket, with an intervening member 20 provided to straddle the gap between the annular member 4 and the reaction member 19.

[0046] The arc-shaped portion of the annular member 4 (reaction member 19) is provided with receiving portions 21 at 90-degree intervals in the circumferential direction. The receiving portions 21 extend radially outward and receive a force acting in the axial direction of the pipe. As shown in FIG. 10 , through holes are formed in the receiving portions 21. An intervening member 20 is inserted across the through holes aligned in the axial direction of the receiving portions 21 formed on the annular member 4 and the reaction member 19, and nuts are provided on both ends of the intervening member 20. When the nuts are tightened toward the receiving portions 21 formed on the annular member 4 and the reaction member 19, and the reaction force from the tightening pulls the annular member 4 toward the reaction member 19, the end of the annular member 4 in the axial direction and the end of the socket of the other pipe 3 come into contact with each other.

[0047] In the simulated pipe 1 according to the third embodiment, the force acting through the receiving portion 21 as the nut provided on the intervening member 20 is tightened increases the abutment state between the end of the annular member 4 in the pipe axis direction and the end of the socket of the other pipe body 3, allowing for more accurate setting of the zero point of the bending angle of the pipe joint. In this embodiment, the annular member 4 and the reaction member 19 have the same shape, but the reaction member 19 can also be a separate member having a different shape from the annular member 4.

[0048] The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. Therefore, the scope of the present invention is defined by the claims, not by the above description, and is intended to include meanings equivalent to the claims and all modifications thereof. [Explanation of symbols]

[0049] 1. Mock pipe for measuring bending angles of pipe joints (mock pipe) 2 One of the pipes 3 The other pipe 4. Contact member (annular member) 4a Divided toroid 5 Displacement gauge holder 6. Displacement gauge 7. Target 8 Switch Box 9 Data Logger 10 Sled member 11 Insertion stand 12, 16 Towing bracket 13 Towing wire 14, 15 Water stop plug 17 Protrusion 18 Circumferential groove 19 Reaction member 20 Intervening member 21 Receiving part P Existing pipe H Departure shaft

Claims

1. A method for measuring the bending angle of a pipe joint, which is constructed by inserting the insertion port of one pipe body (2) into the receiving port of the other pipe body (3), is measured by angle measuring means provided on the pipe bodies (2, 3), a step of installing the angle measuring means inside the tubular body (2, 3); a step of attaching an abutment member (4) having an end portion in the tube axis direction included in a plane having the tube axis of the one tube body (2) as a surface normal to the outer periphery of the insertion port; a step of inserting the insertion port into the receiving port until the end of the abutting member (4) attached to the outer periphery of the insertion port in the pipe axis direction abuts against the end of the receiving port; a step of setting a zero point of the angle measuring means in a state where the end of the abutting member (4) in the pipe axis direction and the end of the socket are in contact with each other; A method for measuring a bending angle of a pipe joint, comprising:

2. 2. A method for measuring the bending angle of a pipe joint as set forth in claim 1, wherein the abutment member (4) is an annular member (4) having an inner surface that conforms to the outer periphery of the one pipe body (2), extending in a band-like shape along the circumferential direction with the same width in the pipe axial direction, and the annular member (4) is constructed by connecting a plurality of divided annular bodies (4a) that are divided circumferentially in the circumferential direction.

3. A method for measuring the bending angle of a pipe fitting as described in claim 2, wherein a circumferential groove (18) is formed on the outer periphery of the insertion port, and a protrusion (17) extending radially inward is formed on the inner surface of each of the plurality of divided annular bodies (4a), and by engaging the protrusion (17) with the circumferential groove (18), the pipe axial positions of the plurality of divided annular bodies (4a) can be aligned.

4. 4. The method for measuring the bending angle of a pipe joint according to claim 1, further comprising the steps of attaching a reaction member (19) to the other pipe body (3), providing an intervening member (20) so as to straddle the abutment member (4) and the reaction member (19), and drawing the abutment member (4) toward the reaction member (19) via the intervening member (20).

5. In a mock pipe for measuring the bending angle of a pipe joint, which is used when measuring the bending angle of a pipe joint, One of the pipe bodies (2) having an insertion port formed therein; the other pipe body (3) having a receiving port into which the insertion port is inserted; an abutment member (4) attached to the outer periphery of the insertion port and having an end portion in the tube axis direction included in a plane having the tube axis of the one tube body (2) as a surface normal; A simulated pipe for measuring the bending angle of a pipe joint, comprising:

6. 6. A mock pipe for measuring the bending angle of a pipe joint as set forth in claim 5, wherein the abutment member (4) is an annular member (4) having an inner surface that conforms to the outer periphery of the one pipe body (2), extending in a band-like shape along the circumferential direction with the same width in the pipe axial direction, and the annular member (4) is constructed by connecting a plurality of divided annular bodies (4 a) that are divided in the circumferential direction in the circumferential direction.

7. 7. A mock pipe for measuring the bending angle of a pipe fitting as described in claim 6, wherein a circumferential groove (18) is formed on the outer periphery of the insertion port, and protrusions (17) extending radially inward are formed on the inner surfaces of the plurality of divided annular bodies (4a), and by engaging the protrusions (17) with the circumferential grooves (18), the pipe axial positions of the plurality of divided annular bodies (4a) can be aligned.

8. 8. A mock pipe for measuring the bending angle of a pipe joint according to claim 5, wherein the abutting member (4) is formed with a receiving portion (21) for receiving a force acting in the pipe axial direction.

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