JPH04248092A - Forming method of insertion port projection section - Google Patents

Abstract

PURPOSE:To provide a method of forming an insertion port projection part, capable of forming a projection part in the insertion port side part of a pipe without requiring much labor. CONSTITUTION:After cutting a pipe and cut down a insertion port 3, a groove section 5 is formed in the external peripheral surface of an insertion port side part 4 in the pipe 1, and a lock ring 6 comprising a mounting bolt 7, on both ends of which screw shafts 7b, whose screws are opposite to each other, are provided threadedly fitted to the opening section 8a of a one piece split ring body 8 beforehand is fitted on this groove section 5. The mounting bolt 7 is rotated in the direction that the opening section 8a becomes narrow to fix the lock ring 6 to the groove section 5 for forming a projection part 2 comprising the lock ring 6 in the insertion port side part 4.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a protrusion on the outer peripheral surface of an insertion side portion of a tube.

0002

2. Description of the Related Art At pipe installation sites, pipes are sometimes cut due to space constraints, and in this case, the insertion end is cut off. A protrusion is formed on the outer circumferential surface of this insertion port to prevent it from coming off when connecting the tube, but if the tube is cut and the insertion hole is cut off, there will be a protrusion on the insertion side of the tube to prevent it from coming off. To avoid this problem, a protrusion is formed on the insertion side of the pipe at the installation site. A conventional method for forming a protrusion on the insertion port side part is to form a groove in the insertion port side part, drill a plurality of screw holes in this groove, and fit the ring body that is to become the protrusion into the groove. There is a bolting method in which a plurality of bolts are used to attach the protrusion, and a welding method in which the ring body that is to become the protrusion is fitted onto the insertion port side portion and welded.

0003

[Problems to be Solved by the Invention] However, in the conventional bolting method described above, a plurality of screw holes must be formed at the pipe installation site and a plurality of bolts must be screwed in, which is a time-consuming problem. was there. In addition, the welding method requires welding work, so welding equipment must be brought to the pipe installation site from time to time, and welding must be performed at the pipe installation site.As with the bolting method, It was time consuming.

The present invention solves the above-mentioned problems, and aims to provide a method for forming an insertion protrusion that can form a protrusion on the insertion side of a tube without much effort. .

[0005]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the method for forming the insertion port protrusion of the present invention is to cut the insertion port by cutting the tube, and then form a groove on the outer circumferential surface of the insertion port side portion of the tube. A lock ring, which is formed by screwing a mounting bolt with threaded shafts in opposite directions at both ends into the opening of the split ring body in advance, is fitted into this groove, and the mounting bolt is inserted into the groove. By rotating the lock ring in the direction in which the opening becomes narrower and fixing the lock ring in the groove, a protrusion made of the lock ring is formed on the insertion opening side portion.

[0006]

[Operation] With the above structure, a groove is formed on the outer circumferential surface of the insertion side of the pipe, a lock ring is fitted into this groove, and the mounting bolt is rotated. A protrusion can be formed on the outer peripheral surface of the part.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In Fig. 2, 1 is a pipe such as a cast iron pipe, and when the pipe is cut at the site where the pipe is laid, the socket 2 side that will be the connection part is left.
The insertion port 3 side is cut off. Since this insertion port 3 is formed with a protrusion 3a for preventing slippage, a protrusion similar to the protrusion 3a is formed on the insertion port side portion 4 of the tube 1 after the pipe is cut.

When forming the insertion protrusion, first, as shown in FIG. 3, after forming a groove 5 on the outer peripheral surface of the insertion part 4 of the tube 1, Apply anti-rust coating to part 4. Next, the lock ring 6 is inserted into the groove 5 of the insertion port side part 4.
(See the phantom line in Figure 3). Here, the lock ring 6 is a single split ring body as shown in FIG. 8, and the split ring body 8 can be tightened easily. Note that 9 in FIG. 6 is a nut welded to the surface facing the opening 8a of the split ring body 8, and the threaded shaft 7b of the mounting bolt 7 is screwed into each nut 9, respectively. Further, the mounting bolts 7 are subjected to anti-rust treatment such as nylon coating.

After fitting the lock ring 6 into the groove 5 of the insertion port side portion 4, the mounting bolt 7 is rotated to narrow the opening 8a, as shown in FIGS. 1 and 4.
Lock ring 6 is fixed in groove 5. Note that the portion of the groove 5 where the mounting bolt 7 is fixed is ground in advance using a grinder or the like so that the mounting bolt 7 can be easily rotated.

[0010] In this way, the lock ring 6 fitted into the groove 5 of the socket side portion 4 allows the protrusion 3a of the socket 3 that was initially provided to be installed without any effort. can be formed.

[0011]

Effects of the Invention As described above, according to the method for forming a socket protrusion of the present invention, a groove is formed on the outer circumferential surface of the socket side portion of the pipe, and a lock ring is externally fitted into this groove to allow installation. A protrusion can be formed on the outer circumferential surface of the insertion side portion of the pipe without any effort by a simple operation of rotating the bolt. As a result, work at the installation site can be carried out efficiently.

[Brief explanation of the drawing]

FIG. 1 is a side view of an inlet side portion of a tube according to an embodiment of the present invention.

FIG. 2 is a sectional view of a tube before an insertion protrusion is formed according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a groove forming step in a method of forming a socket protrusion according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view of a lock ring fixing step in a method of forming a socket protrusion according to an embodiment of the present invention.

FIG. 5 is a front view of a mounting bolt according to an embodiment of the present invention.

FIG. 6 is a front view of a lock ring according to an embodiment of the present invention.

[Explanation of symbols]

1 pipe 3 Socket 4 Inlet side part 5 Groove 6 Lock ring 7 Mounting bolt 7a Hexagonal nut part 7b Screw shaft 8 One split ring body 8a Opening

Claims (1)

[Claims] Claim 1. A method for forming an inlet protrusion in which a protrusion is formed on the outer circumferential surface of an inlet side portion of a tube when cutting the tube, the method comprising: forming a protrusion on the outer circumferential surface of an inlet side portion of a tube, the method comprising: A lock ring is formed by forming a groove on the outer peripheral surface of the side part, and screwing a mounting bolt with threaded shafts in opposite directions at both ends into the groove in advance into the opening of the split ring body. the lock ring is fitted into the slot, and the lock ring is fixed in the groove by rotating the mounting bolt in a direction in which the opening narrows, thereby forming a protrusion made of the lock ring on the socket side portion. How to form protrusions.