JP2001280562A - Locking ring for pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make fine wide-range adjustment of the peripheral length of an insertion port ring 4 during fitting. SOLUTION: An insertion port ring 4 is fitted to an annular groove 5 in a pipeend insertion port 2a to prevent the separation of the insertion port 2a. The insertion port ring 4 of a peripherally one-slit type is tightened freely, with both ends 4a, 4b being blind-riveted 20 by a joint piece 10. Holes 14 in the piece 10 and holes 11 in the end 4a are ten each in number at equal pitches and the pitches of the holes 14 are 9/10 time the pitches of the holes 11. This pitch difference corresponds to a relationship between a main scale and a sub- scale of calipers. Namely, when the diameter of the ring 4 is enlarged or contracted, the same axial centers of the holes 11 and the holes 14 are changed, permitting rivet tightening with the holes 11, 14 having the same axial centers. If there is a 10-pitch difference shift, a right-end hole 11 is made to correspond to the next hole 14 (Fig.(b)), which is used as a reference point for additional adjustment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock ring in a pipe joint for preventing insertion of a metal pipe constituting a pipeline for water supply or the like.

[0002]

2. Description of the Related Art For example, when a ductile cast iron pipe is buried underground to lay a pipe, as shown in FIG. 16, an insertion port 2a of a succeeding pipe 2 is inserted into a receiving port 1a of a preceding pipe 1. In general, they are joined together. Some pipe joints have a structure adapted to expansion and contraction caused by an earthquake or the like. For example, a pipe joint made of an NS type pipe has a centering rubber 3a in an inner annular groove 3b of a receiving port 1a as shown in FIG.
The lock ring 3 is fitted through the
Is provided with an insertion ring 4, and the insertion opening 2a is connected to the receiving port 1.
The insertion ring 4 pushes over the lock ring 3 to get over it, and the distance between the lock ring 3 of the ring 4 and the inner surface wall 1b of the receiving port 1a is equal to the distance between the two pipes 1.
By absorbing the expansion and contraction of 2 and locking the insertion opening ring 4 with the lock ring 3, the insertion opening 2a is prevented from being detached from the receiving opening 1a. In the figure, reference numeral 5 denotes an annular fitting groove of the insertion ring 4;
Is packing, 7 is lining.

As a technique for fitting the insertion ring 4 into the groove 5 of the insertion ring 4 in such a pipe joint having a detachment preventing function, there is a technique disclosed in Japanese Patent Application Laid-Open No. 9-178053. In this technique, the insertion ring 4 is divided into one in the circumferential direction, a connecting piece is bridged over both ends thereof, and the insertion piece is inserted into the groove 5 with the insertion ring 4 fitted at a required position in the groove 5. Are riveted to both ends, and the insertion opening ring 4 is provided in the insertion opening 2a.

In Japanese Utility Model Laid-Open Publication No. 61-14779, the lock ring 3 is divided in a circumferential direction, and connecting pieces are overlapped on both ends of the lock ring 3. A plurality of communication holes of the same size are formed at equal pitches in the longitudinal direction, the pitch of the communication hole at the end and the communication hole of the coupling piece are different, A similar communication hole is also formed at each end, and a connecting tool is inserted into both of the communication holes, and a connecting tool is inserted into a connecting piece having a required diameter of the lock ring 3 and a corresponding communication hole at one end. A technique is disclosed in which the connecting pieces are fastened to both ends of the lock ring by the two connecting tools.

[0005]

The riveting of the prior art described in the above-mentioned prior art is the insertion ring 4.
The rivet insertion hole at one end is formed by positioning the insertion ring 4 after fitting it into the groove 5. For this reason, after the positioning, the insertion opening ring 4 is once removed from the insertion opening 2a to form the insertion hole, and the operation is troublesome. Also, even if an insertion hole is formed in a state where the insertion ring 4 is fitted in the groove 5, it is construction on site,
The operation is complicated.

In the latter technique, fine adjustment of the width of the lock ring divided portion is possible by the function of the main scale and the vernier scale of the caliper by the communication holes having different pitches, but the adjustment width is narrow, and there are many problems. .

An object of the present invention is to widen the adjustment range in the latter technology.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is capable of changing the reference point of the caliper mechanism using communication holes having different pitches. If the reference points can be changed, at each reference point, the lock ring (both the lock ring 3 and the insertion ring 4) can be used based on the vernier function of the caliper that can be exhibited by the communication holes having different pitches. Adjustment of the divided part (expansion and contraction diameter adjustment) can be performed. For this reason, the range of adjustment is wider than that of a single reference point.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the present invention, first, an annular groove is formed on one entire circumference of an inner surface of a receiving pipe of one pipe and an outer face of an insertion port of the other pipe. In the lock ring of the pipe joint having a function of preventing a detachment of an insertion port formed by fitting a split lock ring and forming a projection for engaging with the lock ring on the other surface, the split part In the lock ring in which is overlapped, a plurality of communication holes of the same size are formed at both ends of the lock ring at the same pitch in the length direction of the insertion ring, and the communication holes of the both ends are formed. The pitch is different, and a configuration is adopted in which blind rivets are inserted into corresponding communication holes at both ends of the lock ring at a required diameter, and both ends of the insertion ring are fastened by the blind rivets.

Further, in a lock ring in which a connecting piece is overlapped on the above-mentioned split part and the connecting piece is connected to both ends of the split part, the connecting piece and one end of the lock ring have the same size. A plurality of communication holes are formed at equal pitches in the length direction thereof, and the pitch of the communication hole at the end thereof is different from the pitch of the communication hole of the coupling piece. A hole is formed, a blind rivet is inserted into both of the communication holes, and a blind rivet is inserted into a connection piece having a required diameter of the lock ring and a corresponding communication hole at one end, and connected by the both blind rivets. A structure in which pieces are fastened to both ends of the lock ring is adopted.

If the pitches of the communication holes are different as described above, the inner and outer diameters of the pipe (fitting of the ring) are determined based on the same functions as the main scale and the vernier scale of the caliper at both ends or one end and the connecting piece. Even if the gap of the split portion of the lock ring changes due to the manufacturing tolerance of the joint groove, any one of the communication holes can be riveted. That is, it is possible to sufficiently absorb the tolerance of the inner and outer diameters of the pipe and to perform a strong fastening. At this time,
The pitch of the communication holes is appropriately set according to the degree of adjustment for the change in the gap at the split portion.

Here, the "same size" includes an error that does not impair the absorption such as a tolerance based on the function of the main scale and the vernier scale, and the "correspondence" of the communication hole is the communication hole. Not only when they are located on the same axis, but also when the rivets can be inserted into both insertion holes and fastened without moving the both ends of the lock ring and the connecting piece in the pressed state (required position) on the inner surface of the fitting groove. It shall include the one with a gap. Further, the number of both communication holes on the main scale side and the vernier side may be the same number, but if the number of large pitch insertion holes on the main scale side is larger than that on the vernier side, each of the insertion holes is formed. The adjustment width can be widened by the length.

Next, as one embodiment, the number of both communicating holes at both ends of the lock ring or one end of the lock ring and the connecting piece is set to the same number, and the number is reduced by one from the number of communicating holes having a large pitch. The numerical value obtained by multiplying the pitch is set to be equal to the numerical value obtained by multiplying the number of communication holes having a small pitch by the pitch.

With this arrangement, if a difference in length obtained by multiplying the pitch difference by the number of one of the communication holes occurs from a state in which one end of both communication holes corresponds to each other, the pitch is small. The one end of the communication hole corresponds to the next one of the one end having the larger pitch, and from that state, the displacement is adjusted by the same action (see the embodiment of FIG. 8).

In another embodiment, a plurality of fastening communication holes for the other end of the lock ring and one of the connecting pieces are formed in the longitudinal direction of the lock ring or the connecting piece. The pitch of the communication holes is obtained by multiplying the difference between the pitch between one end of the lock ring and the two communication holes of the connecting piece by the smaller number of communication holes in the length direction (including the number in the case of the same). The length configuration is adopted.

According to this configuration, by selecting the communication hole of the other end or the connecting piece and changing the fastening position of the other end and the connecting piece, the one end and the connecting piece correspond to each other. The reference point of the communication hole changes, and the width corresponding to a change in the pipe outer diameter such as manufacturing tolerance increases (see the examples in FIGS. 7A to 7C). Here, the length obtained by multiplying the pitch difference by the smaller number of the communication holes is that the adjustment width is determined by the number of the corresponding communication holes based on the deviation between the one end and the coupling piece. The corresponding number depends on the smaller number. For example, three and five are determined by the former three, and after the third communication hole corresponds, the reference point is shifted, This is to obtain the same function.

Instead of the blind rivet fastening, screw fastening may be used. At this time, the communication hole at the end of the insertion ring may be a screw hole, but may not be a screw hole but may be fastened with a tap screw.

[0018]

One embodiment is shown in FIGS. 1 to 7, and this embodiment corresponds to the lock ring described in the claims in the groove 5 of the insertion opening 2a in the NS type pipe joint shown in FIG. The insertion ring 4 to be inserted is fitted. The insertion ring 4 is divided into one in the circumferential direction.
b is made thin, and the connecting piece 10 is fastened with the rivet 20 fixed. In this fastening state, the outer peripheral surface of the coupling piece 10 is set to be substantially the same as the outer peripheral surface of the insertion ring 4.

The insert ring 4 and the connecting piece 10 are made of the same material as the pipes 1 and 2 (material not affected by the ionization tendency).
Is preferable, but the material is not particularly limited to a material having no spring property. In addition, a shape memory alloy and a superelastic alloy can also be used for the insertion ring 4, and if these alloys are used,
When the diameter of the pipe 2 is small, it is advantageous from the viewpoint of workability.
That is, when the insertion port ring 4 is attached to a small-diameter tube, the ring 4 made of stainless steel or the like is difficult to expand and contract, and the workability may be deteriorated. If the diameter is forcibly expanded or contracted, plastic deformation or breakage may occur. On the other hand, the shape memory alloy is generally easy to deform, and at a certain temperature, the ring 4 of the shape memory alloy stored so as to expand and contract the diameter to an optimum size for fitting can be inserted into the groove 5. After the diameter has been increased and reduced and fitted into the groove 5, it is heated to the above-mentioned temperature, returned to the original shape, and the ring 4 is fixed, whereby the work can be carried out more smoothly. In addition, the superelastic effect means that even if it is greatly deformed at a temperature higher than the shape recovery temperature,
It means returning to the original shape again when stress is removed. If the ring 4 is made of a superelastic alloy having this characteristic, if it is fitted into the groove 5 at a temperature higher than the shape recovery temperature, its deformation is easy, and Without plastic deformation, the shape recovers at room temperature and the fitting can be performed, and the construction can be performed smoothly.

Five holes 11 are formed at one end 4a of the insertion ring 4 at a pitch A ′ of 9 mm in the length direction thereof.
36 mm), and three holes 12 are formed in the other end 4b at a pitch C ′ of 5 mm in the length direction (C = 10 m).
m, see FIG. 6). The connecting piece 10 has one in its length direction.
Five holes 14 having the same size as the holes 11 are formed at a pitch B ′ of 0 mm (B = 40 mm), and a fixing hole 15 having the same size as the holes 12 is formed at one side thereof. The distance between the fixing hole 15 and the left end hole 14 is as shown in FIG.
In a state where there is no tolerance between the outer surface of the tube and the groove 5 and the insertion ring 4 is simply fitted in the groove 5 only by its elasticity, for example, the fixing hole 15 is coaxial with the center of the three holes 12. Then, the hole 11 at the right end of the one end 4a and the hole 14 at the right end of the coupling piece 10 are set so as to have the same axis (FIG. 6). Also, the fixing hole 15 can be coaxial with the three right end holes 12 (see FIG. 7). In this case,
When the insertion ring 4 is fitted into the groove 5, the diameter does not increase, and the diameter always decreases. The gap between both ends 4a and 4b of the inserted port ring 4 when these referenced gap Y _0. In addition, the reference gap Y ₀ may be in a good press-fit (fitted) state of the insertion ring 4 in which the diameter of the insertion ring 4 is reduced by the C clamp P when there is no tolerance.

When the connecting piece 10 and the one end 4a of the insertion ring 4 are a vernier caliper and a vernier caliper, the pitch difference between the holes 11 and 14 causes the same axis to be adjusted according to the degree of displacement between the two. Holes 11 and 14 will change. That is, in FIG. 7A, in a state where the center of the hole 15 and the center of the hole 12 at the right end are made coincident (coaxial center), one end 4a moves in the direction of the arrow as shown in FIG. When the diameter of the ring 4 is reduced (the gap between both ends 4a and 4b is Y
For example, if it moves by 3 mm, the centers of the fourth holes 11 and 14 from the right side coincide. Thus, 1m
The matching holes 11 and 14 change by m. For this reason,
If the rivets 20 are inserted into the matching holes 11 and 14 and fastened, the reduced diameter state is reliably maintained.

In the case of a displacement of 4 mm or more, as shown in FIG. 7C, when the hole 15 is made to coincide with the hole 12 on the left side, the hole 15 is displaced by 5 mm. The holes 11 and 14 coincide. If the hole 15 is shifted by 9 mm or more, and the hole 15 is further aligned with the hole 12 on the left end, any one of the hole 11 and the hole 1 is similarly shifted to 14 mm.
4 matches. Therefore, in this embodiment, the reference gap Y
It is possible to cope with a displacement from ₀ to a diameter reduction of the gap Y of 14 mm.

From this idea, by setting the pitches A ′ and B ′ of the holes 11 and 14 and the numbers thereof and the number of holes 12 arbitrarily (see FIG. 6), the deviation from the reference gap Y ₀ can be reduced. It can be taken arbitrarily. Also, the reference gap Y ₀ is
Hole 15 is not holes 12 at both ends, if the time corresponding to the middle of the hole 12, reduced diameter or from the reference gap Y ₀ may correspond to both fixed state of enlarged diameter. One hole 12 and a plurality of holes 15 may be provided.

A blind rivet 20 shown in FIG. 5, which can be fastened from only one side, is used as the rivet. The blind rivet 20 is composed of a cylindrical rivet main body 21 and a drawing rod 22 inserted through the main body 21. As shown in FIG. 3A, the holes 11 and 12 of the insertion ring ends 4a and 4b and the holes 14 and 15 of the coupling piece 10 are inserted through
By pulling out the withdrawal rod 22 as shown in FIG. 2B, the ear portion 21a of the main body 21 is bulged by the head portion 22a, and the bulge portion 21a and the upper flange 21b make the insertion ring 4 The two are fastened while holding the connecting piece 10. At this time, since the bulging portion 21a protrudes from the front and back surfaces of the insertion ring 4, a double chamfer 16 or a groove 17 is formed in each of the insertion holes 11, 12, 14, 15, and the chamfer 16 or the groove 17 bulges. It is preferable to store the protrusion 21a (head 22a). As a result, the insertion ring 4 is inserted into the insertion port 2a.
It does not rise from the external use surface, and exhibits a smooth insertion and expansion / contraction function of the insertion opening 2a.

This embodiment has the above configuration.
The mounting operation of this embodiment will be described.
, And the periphery thereof is fastened by a C clamp P, and the insertion ring 4 is pressed into contact with a predetermined position on the inner surface of the groove 5. By this pressing, the rivets 20 are inserted into the corresponding holes 11 and 14 and fastened. At this time, the corresponding holes 11 and 14 may be confirmed by the gauge 25 as shown in FIG. In other words, as shown in FIG. 3A, if they do not correspond to each other, the gauge 25 cannot be inserted into both the holes 11 and 14, and
If the correspondence is made as shown in FIG. 3B, it can be inserted into both holes 11 and 14, and the correspondence can be confirmed. Further, as shown in FIG. 6, numerical values such as 0 to 4 are sequentially assigned to the holes 11 and 14 in the column direction, the gap Y after diameter reduction is measured, and the gap Y and the reference gap Y ₀ are measured. Difference, the difference holes 11, 14, eg 3
mm, the rivets 2 are inserted into the holes 11 and 14 of the numerical value 3.
0 may be inserted.

In each of the above embodiments, the rivet fastening position of the other end 4b of the insertion ring 4 of the connecting piece 10 is changed.
The reference point was changed to increase the adjustment width. However, the number of the communication holes 11 and 14 on the main scale side and the vernier scale side was set to the same number, and the number obtained by subtracting one from the number of the communication holes 14 having a large pitch. Is set to be the same as the value obtained by multiplying the pitch by the number of the communication holes 11 having a small pitch,
For example, in the embodiment of FIG. 8A, if a deviation of a length (10 mm) obtained by multiplying the pitch difference (1 mm) by the number of one communication hole occurs as shown in FIG. The end of the hole 11 corresponds to the insertion hole 14 next to the insertion hole 14 of the one end having a large pitch (the reference point becomes the next insertion hole 14). Is made. In this embodiment, one of the holes 12 and 15 may be plural under the conditions of the above-described embodiment.

In the fastening by the connecting piece 10 described above, the rivet fastening between the connecting piece 10 and the other end 4b of the insertion ring 4 is performed before and after the insertion ring 4 is fitted into the groove 5. Before and after the same pressure welding,
When there are a plurality of holes 2 and 15, the width of the expansion / contraction displacement can be arbitrarily set depending on the selection of the holes.

FIG. 10 shows an embodiment in which both ends 4a and 4b of the insertion ring 4 are overlapped without using the connecting piece 10, and the mode of the holes 11 and 14 is the same as that of the embodiment of FIG. The same shall apply. In each of the above embodiments, including this embodiment, the number of communication holes on the main scale side can be larger than the number of communication holes on the vernier side, and in this case, the caliper of the main scale is The expansion / contraction displacement can be adjusted within the range of the number of communication holes on the main scale side so that measurement can be performed within the range.

In each of the above embodiments, the communication holes 11, 14
Is arbitrary, and further, as shown in FIG.
One end 4a side of the insertion ring 4 is the main scale side, and the connecting piece 1
0 or the other end 4b may be the vernier side (B ′ <A ′, B <
A).

FIGS. 11 to 15 show a state in which a corrosion protection core C made of an elastic material is fitted and fixed to the end of the insertion opening 2a. 11) or an annular step 9a (FIG. 12)
Alternatively, the fixing ring 8 which can be split in the circumferential direction one by one on the step portion 9a
The anticorrosion core C is fixed to the insertion opening 2a by the ring 8. In each of these embodiments, FIG. 13 shows a case where an abrasion-resistant layer a is formed by fusing an ultra-high molecular weight polyethylene film or the like at a position where the anticorrosion core C is easily worn away.
FIG. 15 shows that the upper edge of the anticorrosion core C is interposed on the lower surface of the insertion ring 4 to effectively prevent the core C from peeling off.
The insertion port ring 4 is provided with ribs 8a over its entire length in the length direction to enhance the crimping state of the fixing ring 8. Each of these examples may adopt those features to each other.

In each of the above embodiments, the blind rivet 2
0, the members 4a, 4b and 10 are fastened. However, in the embodiment shown in FIG. 1, the holes 11 and 12 on both ends 4a and 4b of the insertion ring 4 are screw holes. The screw may be fastened by screwing a screw through the holes 14 and 15 into the screw hole. If the tapping screw is used, the holes 11 and the like need not be screw holes. Holes 11, 1
2, 14, 15 may be in the width direction of the ring 4 instead of the radial direction of the ring 4.

In the above embodiments, the insertion ring 4 is used. However, the present invention can be applied to the lock ring 3 shown in FIG. 16 in the same manner as the insertion ring 4, and the same effects can be obtained. In addition, although the embodiment is of the NS type, the present invention can be appropriately applied to other types of pipe joints having a function of preventing detachment by a projection such as an insertion ring and a ring engaged with the projection. Of course.

[0033]

According to the present invention, as described above, the lock ring is provided with a fine adjustment function having a large adjustment width of its circumferential length, so that an optimum degree of fitting of the lock ring can be easily obtained. The degree of fitting of the lock ring is maintained for many years, and the insertion port can be effectively prevented from coming off with respect to expansion and contraction and bending of the joint portion.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of an embodiment.

FIG. 2 is a right side view of the main part cut away in FIG. 1;

FIG. 3 is a perspective view of an insertion ring of the embodiment.

FIG. 4 is a diagram showing a fastening operation of the insertion ring of the embodiment.

FIG. 5 is an operational diagram of the blind rivet of the embodiment.

FIG. 6 is an operation diagram of the embodiment.

FIG. 7 is an operation diagram of the embodiment.

FIG. 8 is an operation diagram of another embodiment.

FIG. 9 is an operation diagram of another embodiment.

FIG. 10 is a perspective view of an insertion ring of another embodiment.

FIG. 11 is a sectional view of another example of the pipe end structure.

FIG. 12 is a sectional view of another example of the pipe end structure.

FIG. 13 is a sectional view of another example of the pipe end structure.

FIG. 14 is a sectional view of another example of the pipe end structure.

FIG. 15 is a sectional view of another example of the pipe end structure.

FIG. 16 is a sectional view of a main part of a pipe joint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 2 Pipe 1a Reception port 2a Insertion port 4 Insertion ring 4a, 4b Insertion ring end part 5 Insertion ring fitting groove 10 Connecting piece 11, 12, 14, 15 Communication hole 16 Chamfer 17 Riveting groove 20 Blind rivet

Claims (4)

[Claims] 1. An inner surface of a receiving port 1a of one tube 1 and another tube 2
An annular groove was formed on one entire circumference of the outer surface of the insertion opening 2a, and lock rings 4 and 3 were fitted in this groove, and a projection for engaging with the lock rings 4 and 3 was formed on the other surface. In the lock rings 4 and 3 of the pipe joint having the function of preventing the insertion opening 2a from being detached, the lock rings 4 and 3 are divided into one in the circumferential direction, and both ends 4a and 4b are overlapped with each other to form a communication hole 11 of the same size. ,
14 are formed at equal pitches in the length direction of the lock ring, and the pitches of the communication holes 11, 14 at both ends 4a, 4b are different, and the number of both communication holes 11, 14 is reduced. In addition to the same number, the value obtained by multiplying the number obtained by subtracting one from the number of communication holes having a large pitch by the pitch is equal to the number obtained by multiplying the number of communication holes having a small pitch by the pitch. A blind rivet 20 is inserted into the corresponding communication holes 11 and 14 of both ends 4a and 4b of the required diameter of the lock ring, and the blind rivet 20 fastens both ends 4a and 4b of the lock ring. And lock rings in fittings. 2. An inner surface of a receiving port 1a of one tube 1 and another tube 2
An annular groove was formed on one entire circumference of the outer surface of the insertion opening 2a, and lock rings 4 and 3 were fitted in this groove, and a projection for engaging with the lock rings 4 and 3 was formed on the other surface. In the lock rings 4 and 3 of the pipe joint having the function of preventing the insertion opening 2a from being detached, the lock rings 3 and 4 are divided into one in the circumferential direction, and the connecting pieces 10 are superimposed on both ends 4a and 4b, and the connection pieces are connected. A plurality of communication holes 11 and 14 having the same size are formed in the piece 10 and one end 4a of the lock ring at the same pitch in the length direction, respectively.
1 and the pitch of the communication holes 14 of the coupling piece 10 are different, and the number of the communication holes 11 and 14 of the lock ring 10 and the two coupling holes 10 of the coupling piece 10 are the same. A value obtained by multiplying the number obtained by subtracting one by the pitch and a value obtained by multiplying the number of communication holes having a small pitch by the pitch are set to be the same, and the coupling piece 10 and the other end 4b of the lock ring are set. Are formed with communication holes 12 and 15, respectively.
A blind rivet 20 is inserted through the blind rivet 20 at the required diameter of the lock ring, and the blind rivet 20 is inserted through the corresponding communication holes 11 and 14 at the required end of the lock ring. The connecting piece 10 is connected to both ends 4a, 4a of the lock ring 4.
b. A lock ring in a pipe joint, which is fastened to b. 3. An inner surface of a receiving port 1a of one tube 1 and another tube 2
An annular groove was formed on one entire circumference of the outer surface of the insertion opening 2a, and lock rings 4 and 3 were fitted in this groove, and a projection for engaging with the lock rings 4 and 3 was formed on the other surface. In the lock ring of the pipe joint having a function of preventing the insertion opening 2a from being detached, the lock ring is divided into one in the circumferential direction, and both ends 4
The connecting pieces 10 are superimposed on a and 4b, and a plurality of communication holes 11 and 14 of the same size are formed at equal pitches in the length direction in the connecting piece 10 and one end 4a of the insertion ring 4 respectively. And the communication hole 11 at the end 4a.
The pitch of the communication hole 14 of the connecting piece 10 is different from that of the connecting piece 10, and the other end 4b of the lock ring and the connecting piece 1
0, a communication hole 1 for fastening the two 4b and 10 to each other.
A plurality of lock rings 2 and 15 are formed in the length direction of the lock ring or the coupling piece 10, and the pitch of the communication holes 12 and 15 is the same as that of the communication hole 1 of the one end 4 a and the coupling piece 10.
Pitch difference of 1, 14 and communication holes 11, 14 in the length direction
The connecting piece 10 and the other end 4b of the lock ring are formed with communication holes 12 and 15 respectively.
A blind rivet 20 is inserted through the blind rivet 20, and the blind rivet 20 is inserted through the corresponding communication holes 11 and 14 of the connecting piece 10 and the one end 4a at the required diameter of the lock ring. The coupling piece 10 is provided at both ends 4a, 4b of the lock ring.
A lock ring in a pipe joint, wherein the lock ring is fastened to a pipe joint. 4. The pipe joint insertion structure according to claim 1, wherein the blind rivet 20 is replaced with a screw instead of the blind rivet 20.