JPS59190594A - Manufacture of insulating pipe joint - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a renal pipe joint having an electrically insulating function.

In general, this type of insulated pipe fitting is, for example, Conc IJ-1-
In metal piping installed across concrete and soil, it is used interposed in the metal piping to interrupt and insulate the current caused by local batteries that may form between the concrete and soil. Ru.

With this type of insulation, the applicant proposed the configuration shown in Figure 1 (Utility Application No. 186, 1982).
No. 58). This previously proposed insulated pipe joint is one for connecting pipes.
A pair of inner metal fRiW] a, lb,:, each of these inner cylinder tubes +8. , 11) Opposing 'l::,: An annular electrically insulating backing 2 made of asbestos, which is interposed and pressed between the surfaces, and an outer cylindrical material with a space between each inner cylindrical body Ia and Ib. Both ends of each inner cylindrical tube 1a, lb are wrapped around the periphery from both ends r'f1t, 3a, 3bK, which are arranged concentrically around the periphery and can be bent into the inner tube 1Ill. I] (consists of a metal outer cylindrical tube 3 which is arranged in a manner similar to the above, and 4 electrically insulating reinforcing resin insulating stones which are filled between the outer cylindrical tubes and hardened to integrate the two, It is something that

However, the insulation pipe joint of the lever is expanded/(Secondly, -4
First, the inner shears are arranged on the same axis, and the electrically insulating backing 2 is interposed between the opposing IW surfaces under pressure. A first cylindrical pipe 3 is placed around the outer periphery at a distance of , and both anchor portions 1 a and 31 of the outer cylindrical pipe 3 are bent inward as specified, and further, among these, Outer tube] Between a, a, and 3 (
/? It is necessary to fill the insulating layer with C insulating material and perform a curing process, and manufacturing operations that satisfy these conditions are not necessarily easy, and proposals for effective manufacturing methods are required.

In view of these circumstances, the present invention provides a method for manufacturing mj non-detachable pipe joints in a simple, easy-to-work, and mass-producible manner under given conditions. This is a manufacturing method that uses tools and molds.

Hereinafter, one implementation of the method of the present invention jMt1 will be explained in detail with reference to FIGS. 2 and 3.

Fig. 2 shows a pair of inner tubes 1a,]l) and electrically insulating backing 2 assembled and set in a setting jig, and Fig. 3 shows this set together with an outer tube 3 in a molded metal. It is assembled into a mold, both ends of the outer cylindrical tube 3 are molded, and the mixed AJ 4 is filled and hardened to show the bulged state.

First of all, as is clear from FIG.
It consists of a mold jig 5''+ and a bowl-shaped anchor 5b, and these jigs 5a, 51) connect the small diameter and cut opposing ends 6b of the lower mold side to the opposite ends 6b of the upper mold side. The same 1q11 core J- is slid on the opposite end portion 6a, which has a large diameter, with a precision 1' (it is possible to fold the silk together by folding it down).
The opposing peripheral surfaces of each of the inner cylinders 21,
] t) by inserting the inner periphery and inserting the receiver, and step part 3.
a, 8'b and the fitting surface 7a, , 71 for holding at a certain position 11mm and 1but' - mold side facing isolation', the above-mentioned electrical insulation on the outer peripheral surface of g6a. Insert the backing 2 into the support 1-11.
Engagement surfaces 9a, 9b and pressing step portions which are engaged and positioned by the molding die G, respectively, are formed into (11).

(As is clear from Section 31) 1, the molding molds used for the IC are powered by a pair of lower molds 1a and 1a, and lower molds l1l). Mold 111)
is generally fixed to the base plate 1 of the molding machine (not shown), and the upper mold 1-a is raised and lowered with respect to the lower mold 111) by known means to perform mold alignment. . The molding space opened on the lower side of the lower mold 11b has an inner circumferential surface i2b into which the outer cylindrical tube 3 is positioned slightly deeper and receives the inner circumferential surface i2b, and a lower part of the i'd surface 121). The molding surface 13b bends slightly and reaches the step 141], and this step rises slightly from the step 4b] double bottom: 'fG]
5b and the inner peripheral surface at the center of this bottom surface 15b], 2
An engagement hole 161) into which the engagement surface 91 of the lower die jig 5b is fitted and engaged is formed concentrically with the lower die jig 5b, and
The upper left mold]) A is opened downward [1] and the outer cylindrical pipe corresponds to the molding space of the lower mold 11b. An inner peripheral surface 12a that can position and receive 3 to a required depth, and a stepped portion which is cut off from the - part of this inner periphery 1rll 12a]
The molding surface 13a reaching 48 and this step], slightly K]7 from 4'a to the inner circumferential surface 122I at the center of the top surface 15a.
The engaging hole 16a into which the engaging surface 9b of the 42-type jig 5a is inserted and engaged is formed concentrically with the L part mold of (L part mold)']a, [)1■ The melt of the insulating material 4, which is an electrically insulating reinforcing resin, is carbonated.

Runner introducing the melt mixture of unsaturated polyester, glass fibers, and other additives such as hardeners]7
．． A gate 18 is formed for filling the molding space under pressure.

The insulated pipe joint can be manufactured using the Cera l-jig and the molding die in the following manner.

As shown in FIG. 2, the inner cylinder tubes 1a and l l are attached to the fitting surface 7a of the upper mold jig 5a and the fitting surface 7b of the lower mold jig 5b, respectively. ) until it hits the stepped portions 8a and 81], and separately, an electrically insulating punch 2 is temporarily inserted into the opposite end 6b of the large jig 51]. Afterwards, each of these jigs 5a,
5b is slidably fitted between its opposing M portions 6a and 6b.

Therefore, in this way, the upper press and lower mold jigs 5a, 51)
In the case where the inner tubes are combined and fitted together, each inner cylinder tube]
a, , ], b and nokusoking 2 are λl
The VCs are identical and are butted against each other on the center, and the backing 2 is interposed between each inner cylinder tube 1a and lb without being compressed, and each set is made.

Next, as described above, the upper die and the lower die jigs 5a and 5b are combined, and then the shaped part C is formed at the end.
1l"'J"',i'i'f tool 5bt [Drain II
II Ob is fitted into the engagement hole 16b of the lower mold 111] so that it hits the pressing step 10b or the bottom surface 15b.
By inserting each end of C1 into the outer cylindrical tube 3 which has not yet been bent, the outer cylindrical tube 3 is also shortened, and the insertion depth is concentric with the molding surface 13b, even though it is in a straight line. Retained.

Then, when the lower mold]]b is suppressed) L is raised, the outer cylinder part 3 starts to fit into the inner peripheral surface of the upper mold], ], a]2a, and then its engagement hole]6a+ /rc upper model night 5
The engaging surface 9a of a begins to be inserted.

And when this pressure increases further, the Gui Tsutsujaku...
: Both ends of 3, here upper and lower ends 3a, 3b, respectively, molding surfaces 13a, 13b of each mold 11a, llb.
As a result, the molding can be completed by bending inward until it hits the stepped portions ], 4 a, ] 4 b, and along with the forming, /
r is the pressing step of the upper die jig 5a] Oa#, i 1:
J part mold]], the top surface 15aVC of a butts into each jig 5a, 5b II-tl, D Iteha inside the pot? A compressive force acts between iU t's, ' ] a, ] tl, and the clamping 2 is squeezed, and the molding is completed.
That is, the upper mold is combined with the upper mold 11a or the lower mold 11b, and the inside of the pot is ``A' (+2・Ia, lb, and the electric cutoff is 2.2', outside f; H3. ' 3 is positioned on a predetermined surface, and it becomes a positional condition for manufacturing.

Next, the molten insulation 4 from the gate 18 of the upper mold 11a is injected under pressure. ring 2 and both ends 3
a, 31) is bent through the inner side 11 to fill the space between it and the outer cylinder tube 3, and as is known in the art, each mold] 1 a,
] ] l) is thermally hardened by heating from a heater or the like built in, and the inner tubes 1a, ]b and the outer tube 3 are integrated with the backing 2 in a compressed state.

Then, by lowering the lower mold j-]b and separating it from the upper mold 1a and lifting it from the upper mold 11) using an ejector, and removing the L-shaped jig 5a and the lower mold jig 5b, respectively. Therefore, the desired insulated pipe joint can be obtained.

As detailed above, according to the method of the present invention, a pair of metal inner cylindrical pipes for connecting the pipes, and an 'IL' which is squeezed between the two end faces of each inner cylindrical pipe, An outer cylindrical backing is arranged concentrically at intervals around the outer periphery of each inner cylindrical tube, and an outer cylindrical tube with both ends bent inward, and a filling hardening type backing is provided between each inner cylindrical tube and the outer cylindrical tube. Using silk upper and lower mold jigs, each inner T: ?j
Since the tubes and the ``commercial insulating banogging'' are held in place, they can be easily and reliably held on the same axis, and in this way, each inner cylindrical tube and the The upper mold and lower mold jigs holding electrical insulation (Paso Gink) are placed in the center of the molding space of the lower mold, and the outer m pipe is inserted into the inner peripheral surface of the mold. This outer cylinder 94 can also be positioned concentrically,
In addition, this lower mold and the -1-9 part mold that are matched with it have a forming surface for inwardly bending both ends of the outer tube, and a ten-form and a lower mold during the molding process. Since a component that applies a predetermined compressive force to each inner tube via a jig is provided, the bending of the outer tube surface J: iA and the pinching of the electrically insulating backing can be performed simultaneously. Moreover, after this molding, the same mold can be used to fill and harden the insulation ∆ in the rolled state, and therefore manufacturing that fully satisfies the given conditions can be carried out by a simple process. '4N?' with excellent workability and n1 productivity. It has a long length.

[Brief explanation of drawings]

Fig. 1 is a partially longitudinal side view illustrating an insulated pipe joint manufactured by the method of the present invention, and Figs. 2 and 3 are examples of the reverse side of the method of the present invention. FIG. 2 is a partially vertical side view of a set state of , and a cross-sectional view showing a molding state in a molding die. Ia, lb... A pair of inner tubes, 2 - Electrically insulating backing, 3... Outer tube, 3a, 3b... Both ends of the outer tube, 4 - Insulating phase made of electrically insulating reinforced resin , 5a, 5b
-1 set of upper mold and lower mold jigs, 6. a, 5b...opposite end,
7a, 7b...fitting surface, 8a, 8b--stepped portion,
9a, 9b-engaging surface, ]Oa, ]Ob...pressing step portion,
jla, Ilb...1 set of upper and lower molds, 12a,
12b-inner peripheral surface, 13a, 13b - molding surface,] 4
a,, 14 b,, step, 15a,' I 5 b
・Bottom surface, top surface, 7...Runner, 18...Gate. Patent applicant: Nippon Steel Pipe Fittings Co., Ltd. Agent Patent attorney: Takashi Suzue - Figure 2 1 Figure 3

Claims (1)

[Claims] Arrangement 7/1: A pair of metal inner sieve tubes of the connecting body, an electrically insulating backing that is pressed between the facing *a m1 of each inner N tube, and a predetermined backing around the outer periphery of each inner cylindrical tube. Insulation consisting of an outer cylindrical tube arranged concentrically at intervals and with both ends bent inward, and an electrically insulating reinforced resin filled and hardened between each inner tube and the outer cylindrical tube. A method for manufacturing a pipe joint, the method comprising:
Using a set of upper mold and lower mold jigs that are fitted and combined in the axial direction, each of the inner cylinder tubes is placed at a predetermined position on each jig.
) The electrically insulating backing is inserted and held between the opposing 191 (with the electrically insulating backing interposed therebetween, and then the combined -1- and lower molds are fitted together and concentrically (arranged) around the outer periphery thereof. The outer cylindrical tube is fitted into a pair of upper and lower molding molds each having a suppressing part and a forming part, and as the upper and lower parts 1 and the molding molds are pressed together,
The inner cylindrical tubes are compressed by the suppressing part to create the electrically insulating banking, and at the same time, both ends of the outer cylindrical tube are bent inward by the forming part, and then wait for the completion of the molding. A method for manufacturing an insulated pipe joint, characterized in that the reinforcing resin filler is introduced under pressure into a molding die, and the reinforcing resin is filled and hardened between each of the inner tubes and the outer tube.