JPS6052349B2 - pipe fittings - Google Patents

Description

[Detailed description of the invention] The present invention relates to a pipe joint.

Conventionally, as pipe joints, for example, Japanese Patent Publication No. 51-1621
As described in Publication No. 5 (see Fig. 3), it consists of a socket body 1' made of vinyl chloride and a cylindrical body 2' made of corrosion-resistant aluminum. It fits into an annular recess 3' formed on the periphery to prevent its axial movement, and its inner peripheral surface extends from the annular protrusion 5' formed on the central inner periphery toward the mouth end. Accordingly, it has been proposed that the tapered surfaces 4', 4' are formed so that the diameter increases, and the double-ply vinyl chloride pipe portion is tightly fitted onto these surfaces.

However, in the conventional socket body 1' as described above, the fitting between the socket body 1' and the double pipe is insufficient, and the internal fluid seeps into the end face of the double pipe and the cylindrical body 2'. The disadvantage was that the end face and the cylindrical body 2' could not be sufficiently protected from corrosion. The present invention has been made for the purpose of solving the conventional drawbacks as described above, and its gist is that a female threaded portion is provided on the inner circumferential surface of the end portion, and a female screw portion is provided on the inner circumferential surface of the deep portion along the circumferential direction. A synthetic resin cylindrical body with a female thread on the inner circumferential surface of the end is fitted into the inner part of the metal pipe joint body with a recess, and a male thread on the outer circumferential surface of the synthetic resin cylindrical body. A short flanged cylindrical body having a flange portion provided with a flange portion is screwed together, and an annular elastic body is inserted between the flanged short cylindrical body and the synthetic resin cylindrical body. It is something.

Hereinafter, the present invention will be explained with reference to embodiments of the drawings.

FIG. 1 is a sectional view showing one embodiment of the present invention. Reference numeral 1 denotes an elbow-type metal pipe joint body, which is provided with internal threads 11, 11 on the inner circumferential surface of both ends, and a wide recess 12 along the circumferential direction on the inner circumferential surface of the deep part thereof.

Reference numeral 2 is a cylindrical body made of synthetic resin, the outer circumferential surface of which is shaped to correspond to the recess 12 of the metal pipe fitting body 1, and female threaded portions 21, 21 formed on the inner circumferential surface of both ends of the metal tube fitting body 1. It is provided so as to be continuous with the female threaded portions 11, 11, and a convex portion 22 is provided in the inner part thereof along the circumferential direction.

A synthetic resin cylindrical portal body 2 is placed in the recess 12 of the metal pipe joint body 1.
are fitted by injection molding.

Reference numerals 3, 3 are short cylindrical bodies with flanges, and flanges 32, 32 are provided outside one end of the short cylindrical parts 31, 31, and a synthetic resin cylindrical body 2 is provided on the outer peripheral surface of the flanges 32, 32. Male threaded parts 321, 3 screws 21 are provided, which are screwed into the female threaded parts 21, 21 of the short cylindrical part 3.
Projections 311, 311 along the circumferential direction are provided on the outer peripheral surfaces of 1 and 31.
A notch 312 along the axial direction is provided at the end of the short cylindrical portions 31, 31 on which the flanges 32, 32 are not provided.
312... are provided.

4, 4 is an annular elastic body, and a plurality of flanges 42, 42, . . . are provided outside one end of the cylindrical portions 41, 41.

The male threaded portions of the flanges 32, 32 of the short flanged cylindrical bodies 3, 3 are screwed into the female threaded portions 21, 21 of the synthetic resin cylindrical body 2 fitted into the recess 12 of the metal pipe joint body 1. , short cylindrical body with flange 3,
3 and the synthetic resin cylindrical body 2, 2, an annular elastic body 4, 4
are inserted, and the flanged short cylinder bodies 3, 3 and the annular elastic bodies 4, 4
A pipe joint is formed in which a pipe is fitted inside.

FIG. 2 is a sectional view illustrating one mode of use of the pipe joint of the embodiment shown in FIG. 1.

Reference numerals 5 and 5 refer to inner-surface-treated steel pipes, in which corrosion-resistant inner coating layers 52, 52 are provided on the inner surfaces of the steel pipes 51, 51.
, 51 are provided with male threaded portions 511, 511 on the outer circumferential surfaces of the ends thereof.

The male threaded portions 5 of the internally coated steel pipes 5, 5 are attached to the female threaded portions 11, 11 of the metal pipe fitting main body 1 of the pipe joint and the female threaded portions 21, 21 of the synthetic resin cylindrical body 2 provided so as to be continuous therewith.
11 and 511, the short cylindrical portions 31 of the flanged short cylindrical bodies 3, 3 are attached to the inner surface coating layers 52, 52 of the inner cladding tubes 5, 5.
, 31 contact the protrusions 311, 311 provided on the outer circumferential surface of the tubes 31, and the internal fluid is sheeted at this portion. Or, while being sealed at the threaded part, the end surfaces of the inner-coated steel pipes 5, 5 and the flanges 3 of the flanged short cylinders 3, 3 are sealed by the annular packings 4, 4.
2 and 32 are sealed, and the internally coated steel pipe 5,
This prevents corrosion from seeping into the end face of pipe joint 5 and the metal pipe joint body 1.

In the embodiment described above, the short cylindrical portion 3 of the flanged short cylindrical bodies 3, 3
Although a case has been described in which the protrusions 311, 311 are provided on the outer peripheral surfaces of the parts 1, 31, the protrusions 311, 311 are not necessarily essential.

If the protrusions 311, 311 are not provided, when the internally coated pipe is connected to the pipe joint, the outer peripheral surface of the short cylindrical part of the flanged short cylinder will come into contact with the inner peripheral surface of the internally coated layer of the internally coated steel pipe. A seal is created between the two. In this case as well, as described above, the annular packing can be used to complete the seal as appropriate. As described above, in the pipe joint of the present invention, a synthetic resin cylindrical body having a female threaded portion on the inner circumferential surface of the end is fitted into a recess in the deep part of the metal pipe joint body, and the synthetic resin cylinder A short flanged cylindrical body having a flange having a male thread on its outer peripheral surface is screwed onto the shaped body, and an annular elastic body is interposed between the flanged short cylindrical body and the synthetic resin cylindrical body. When an internally coated steel pipe is connected to this pipe joint, there is a gap between the inner coating layer of the internally coated steel pipe and the short cylindrical part of the flanged short cylinder, and the synthetic resin cylindrical body and the flanged short cylinder. ”
The internal fluid is sealed between the abutting part or the threaded part with the cylindrical body and by the annular packing, and the internal fluid does not seep into the end face of the inner-coated steel pipe and the metal pipe fitting body. Can provide sufficient corrosion protection.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention, FIG. 2 is a cross-sectional view explaining one mode of use of the embodiment of FIG. 1, and FIG. 3 is a cross-sectional view explaining a conventional one. Explanation of symbols, 1...Metal pipe fitting body, 2...
... Synthetic resin cylindrical body, 3... Short cylindrical body with flange,
4... Annular elastic body, 5... Inner coated steel pipe, 11... Female threaded portion, 12... Concave portion,
21... Female thread part, 22... Convex part, 31
...Short cylindrical body, 32...Brim portion, 311.
...Protrusion, 321...Male thread part.

Claims (1)

[Scope of Claims] 1. A female threaded portion is provided on the inner circumferential surface of the end portion, and a female threaded portion is provided on the inner circumferential surface of the end portion in the deep part of the metal pipe fitting main body, which is provided with a recessed portion along the circumferential direction on the inner circumferential surface of the deep portion. A cylindrical body made of a synthetic resin having a cylindrical part is fitted into the cylindrical body, and a short cylindrical body with a flange, which has a flange having a male threaded part on its outer peripheral surface, is screwed into the cylindrical body. A pipe joint in which an annular elastic body is inserted between a short cylindrical body with a flange and the synthetic resin cylindrical body. 2. The pipe joint according to claim 1, wherein the flanged short cylindrical body is provided with protrusions along the circumferential direction on the outer peripheral surface of the short cylindrical portion.