JPH03140691A - Pipe joint - Google Patents

Abstract

PURPOSE:To prevent water from penetrating into a void between a metallic joint and a core by forming a hole, reaching to an inner surface of the metallic joint, in an accepting part, in the metallic joint built in with a resin core having the pipe end accepting part of a lining pipe in the inner surface. CONSTITUTION:A silicon-based sealant 24, by way of example, is applied to the vicinity of an upper part of an accepting part 20, and an internal thread 12 of a connector 10 is screwed in an external thread 26 of a lining pipe 18. When a pipe end of this lining pipe 18 pushes the sealant 24 into a bottom part of the accepting part 20 and further screws in the lining pipe 18, the sealant 24 is extruded into a void 28 between a metallic joint and a core 16 by way of plural numbers of holes 22, sealing this void 28. Consequently, any penetration of water into the void is preventable and, what is more, rusting and corrosion on an inner surface of the metallic joint 14 is preventable as well. Moreover, a special process for charging the sealant 24 falls into disuse.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to pipe fittings, particularly for water supplies, for example.

This invention relates to pipe fittings used as piping materials for building equipment, such as piping materials for hot water supply or air conditioning.

[Prior art]

Referring to FIG. 5, a conventional pipe joint 1 includes a core 3 made of a synthetic resin such as heat-resistant vinyl chloride on the inner surface of a metal joint 2 made of, for example, malleable cast iron. For example, a silicon-based sealant 5 was filled in the vicinity of the upper part of the tube end receiving part 4.

Then, at the time of connection, the female thread 6 formed on the inner peripheral surface of the end portion of the metal joint 2 and the male thread 8 of the lining pipe 7 are screwed together.

[Problem to be solved by the invention]

In such a conventional pipe fitting 1, the metal fitting 2 and the core 3 are not bonded to each other, creating a gap 9, and the inner surface of the metal fitting 2 is treated with a primer using, for example, an epoxy resin. It was just that. Therefore, there is a problem in that water enters the gap 9 after construction, causing rust and corrosion on the inner surface of the metal joint 2.

Therefore, the main object of the present invention is to provide a pipe joint in which water does not enter the gap between the metal joint and the core.

[Means to solve the problem]

Simply put, the present invention is a pipe joint that includes a resin core having a receiving part on the inner surface of the metal joint for receiving the end of a lining pipe, in which a hole is formed in the receiving part to reach the inner surface of the metal joint. This is a pipe joint characterized by:

[Effect]

After applying a sealant, such as silicone, to the receiving part of the core, the lining tube is screwed into the metal joint. Then, the sealant enters through the hole, spreads into the gap between the metal joint and the core, and seals this gap.

〔Effect of the invention〕

According to this invention, since the gap between the metal joint and the core is sealed with the sealant, water can be prevented from entering, and rust and corrosion on the inner surface of the metal joint can be prevented. Moreover, no special process is required to seal the gap, and it is very simple, as all that is required is to apply a sealant and screw in the lining pipe in the same way as in the past.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[Example] Referring to FIGS. 1A to 1C, a pipe joint 10 of this example includes an elbow-shaped metal joint 14 made of malleable cast iron, for example, and having internal threads 12 formed on the inner peripheral surface of both ends thereof. . Although not shown, on the inner and outer surfaces of the metal joint 14,
For example, a primer treatment using epoxy resin is performed.

Further, a core 16 made of heat-resistant vinyl chloride, for example, is formed on the inner surface of the metal joint 14, and receiving portions 20 for receiving the pipe ends of the lining pipe 18 are formed at both ends of the core 16, respectively. What should be noted here is that a plurality of holes 22 are formed at the bottom of each receiving portion 20 to reach the outer inner surface of the curved portion of the metal joint 14.

At the time of connection, first, a silicon-based sealant 24, for example, is applied to the vicinity of the upper portion of the receiving portion 20. Then, as shown in FIG. 1C, the female thread 12 of the pipe joint 10 and the male thread 26 of the lining pipe 18 are screwed together.

At this time, the end of the lining tube pushes the sealant 24 into the bottom of the receiving portion 20. Then, when the lining pipe 18 is further screwed in, the sealant 24 is pushed out through the hole 22 into the gap 28 between the metal joint 14 and the core 16, and seals this gap 28.

In this way, in the pipe joint 10, the gap 28 is sealed by the sealant 24, so water can be prevented from entering there.
Rust and corrosion on the inner surface of the metal joint 14 can be prevented. Moreover, no special process is required to fill the sealant 24.
It is very simple because it is only necessary to screw in the lining pipe 18 in the same way as in the conventional case. Furthermore, the lining pipe 18
Needless to say, the tube end can be protected against corrosion by being in close contact with the sealant 24 as in the conventional case.

Note that if the amount of sealant 24 applied to the receiving part 20 is too small, the gap 28 cannot be sufficiently sealed. It is necessary to apply an optimum amount of sealant 24.

However, if the amount of sealant 24 applied is too large, conventionally the excess sealant would spill out into the lining pipe 18 as shown in FIG. If the sealant 24 is pushed out inward, even if the amount of sealant 24 is too large, the excess sealant will flow into the gap 2.
Since it falls within 8, there is an advantage that such protrusion does not occur.

In this embodiment, as shown in FIGS. 1A and 1B, only the holes 22 that reach the outer inner surface of the curved portion of the metal joint 14 are formed, and those that reach the inner inner surface of the curved portion are formed. However, since the sealant is soft, it spreads from the outside of the curved part and sufficiently seals the inside of the curved part, so there is no problem.In addition, in this embodiment, the hole 22 is inserted into the lining pipe 18. Sometimes the sealant 24 fills the void 2.
In addition to the elbow-shaped pipe joint as in the above-mentioned embodiment, the present invention is also applicable to the elbow-shaped pipe joint shown in FIG. Alternatively, it may be applied to a straight type or cheese type pipe joint as shown in FIG. In these cases,
The angle or position of the hole is determined depending on the shape of the pipe joint.

That is, in a straight pipe joint as shown in FIG. 3, the hole 22' is formed obliquely with respect to the pipe axis so as to reach the inner surface of the metal joint 14'.

In addition, in a cheese-shaped pipe joint as shown in FIG. 4, in which a branch part 32 is provided on the central side of a straight part 30 having openings at both ends, the straight part 30 is opened from the bottom of the receiving part 20' of the branch part 32. The hole 22' may be formed so as to reach the inner surface of the metal joint straightly.

[Brief explanation of the drawing]

1A to 1C are illustrative views showing one embodiment of the present invention, in which FIG. 1A is a sectional view, FIG. 1B is a side view, and FIG. 1C is a sectional view showing a state in which a lining pipe is connected. be. FIG. 2 is a partial sectional view showing a state in which the sealant has protruded into the lining pipe. FIGS. 3 and 4 are sectional views showing other embodiments of the present invention, respectively. FIG. 5 is a sectional view showing the prior art. In the figure, 10 is a pipe joint, 12 is a female thread, 14 is a metal joint, 16.16' is a core, 18 is a lining pipe, and 20
．． 20' is a receiving part, 22.22' is a hole, 24 is a sealant, and 28.28' is a void.

Claims (1)

[Scope of Claims] A pipe joint having a built-in resin core having a receiving part for receiving the pipe end of a lining pipe on the inner surface of the metal joint, wherein a hole reaching the inner surface of the metal joint is formed in the receiving part. Features: Pipe joints.