JPS62188884A - 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] [Industrial application field] TECHNICAL FIELD The present invention relates to pipe fittings, and in particular to stainless steel pipe fittings.

[Conventional technology and its problems]

Pipe fittings manufactured using the same method are provided. However, for stainless steel tubes used in places where corrosion resistance is required, such as heat exchangers, the ends of the tubes are either butt welded into one piece, or they are removable, so-called telescopic and flexible tubes. pipe fittings were used. However, the telescoping flexible pipe joint has problems in that it has a large number of parts and a complicated structure.

〔the purpose〕

An object of the present invention is to solve these conventional problems and provide a stainless steel pipe joint that is detachable, has a small number of parts, and has a simple structure.

Means for Solving Problem C] The pipe joint according to the present invention includes a connected pipe made of stainless steel having an enlarged conical flare portion formed on the end surface, and a tapered short pipe that is tightly attached to the inner surface of the flare portion. It includes a tubular sealing member and a stainless steel joint main body having a tapered end and tightly attached to the inner surface of the sealing member.

[Effect]

According to the above structure, the sealing member is held between the pipe to be connected and the joint body, and therefore, by screwing the bag nand to the joint body, a detachable and structurally economical pipe joint can be assembled.

〔Example〕

Hereinafter, the present invention will be explained in detail based on illustrated embodiments.

In FIG. 1, reference numeral 1 denotes a pipe joint in an assembled state, which includes a stainless steel joint body 4 having male threaded portions 2 near both ends, and both ends 3 having a tapered shape, and an end face. A connected vibro made of stainless steel forming a flared portion 5 enlarged into a conical shape, a tapered short tubular sealing member 7 that is sandwiched between the connected vibro and the joint body 4 for sealing, and a female threaded rod portion 8. and a stainless steel cap nut 9 which is screwed onto the male threaded rod portion 2 of the joint body 4.

Specifically, as shown in FIG. 2, the joint body 4 and the cap nut 9 are made of short stainless steel cylindrical pipes, and are processed into a predetermined shape by cold forging and subsequent machining. That is, the joint body 4 has a male threaded portion 2 of a predetermined length formed on the outer periphery near its end face, and the tip of the male threaded portion 2 is formed into a rounded taper shape. Further, the inner peripheral surface of the joint body 4 has a large diameter portion 10 having a predetermined hole penetrated therethrough.
In addition, the end portion 3 has a small diameter portion 11 which is curved to correspond to the outer circumferential surface and is formed to be slightly smaller than the large diameter portion 10. Note that reference numeral 12 is a locking portion formed in a hexagonal shape and engaged with a tool such as a spanner, and is still the cold forging described above.

The vibro to be connected is made of hard stainless steel, and has a flared end portion 5 which is enlarged at a predetermined angle into a conical shape.

Furthermore, the Taber tubular sealing member 7 is thin-walled,
A hole 1 made of rubber or resin and having approximately the same diameter as the joint body 4
4 is installed through the joint body 4, and an inner surface portion 15 and an outer surface portion 16 are respectively formed so that the joint body 4 and the vibro to be connected can be brought into close contact with each other.
is formed.

The cap nut 9 is manufactured from a short stainless steel pipe by cold forging and machining, and has an outer circumferential surface 17 in a hexagonal shape and an inner circumferential surface 18 with a predetermined length to be screwed onto the joint body 4. A female threaded portion 8 and a hole 19 through which the connected vibro can be inserted are provided, and the core 19 and the female threaded portion 8 have approximately the same inclination angle as the flared portion 5 of the connected vibro. They are merged via the formed slope portion 20.

Thus, the joint body 4, the seal member 7, and the connected vibro formed as described above are sequentially joined, and the cap nut 9
The inclined portion 20 and the flared portion 5 of the vibro to be connected are in close contact, and the female threaded portion 8 of the cap nut 9 is screwed onto the male threaded portion 2 of the joint body 4, so that it can be detachably assembled.

The pipe joint assembled in this way is made of stainless steel, so it has excellent corrosion resistance, has a small number of parts, and is easy to assemble. There is no big difference in diameter, and there is less pressure loss during circulation. It goes without saying that one end 3 of the joint body 4 can also be assembled using similar components.

FIG. 3 shows another embodiment in which the joint body 4 is an elbow. The elbow-shaped joint body 4 is made by welding two pipe members 21, 21 of the same shape to each other. 24 is a welding beat. Furthermore, both ends 3
．． 3 is similar to the previous embodiment and is assembled with the same correlation as in FIG.

Next, a method for manufacturing the joint body 4 having an elbow shape will be described in detail with reference to FIG. 4.

In FIG. CI), 26 is a stainless steel cylindrical pipe cut into predetermined short dimensions. As shown in (U) of the cylindrical pipe 26, both end portions 3 and the end portion 3 of the inner surface 27, 27 of the cylindrical pipe 26 are cut using a lathe to form a chamfered portion 28. Next, a predetermined cold forging process is performed to form the cylindrical pipe 26.
The outer peripheral surface of the pipe 26 is formed into a tapered shape with both ends 3.3 curved, and a groove 29 is formed approximately in the center of the cylindrical pipe 26. In the end portion 3, the chamfered portion 28 is substantially parallel to the axis, forming a small diameter portion 11. In this way, if cold forging is performed after the chamfered portion 28 is formed by cutting, the cutting after forging can be omitted, and even when cutting is performed, there is less machining allowance. This method is particularly effective for manufacturing a joint body 4 having a shape that is difficult to process, such as an elbow shape.

Thereafter, as shown in [IV], threads are machined near both ends 3.3, and a male threaded part 2 of a predetermined length is
．． 2 is formed. Next, AB at an angle θ of 45 degrees from the contact points A and A' of the radius forming the groove 29.
The tube members 21 and 21 are cut along lines A' and A'B', and the central portion 30 is removed to form two tube members 21, 21.

Next, the joint surfaces are welded with the cutting lines AB and A'B' corresponding to each other to obtain the elbow shown in FIG. 3.

Manufacturing from stainless steel pipes in this way has the advantage of requiring less waste material and being able to be manufactured at low cost. In addition,
Fig. 5 shows another manufacturing method, in which a short stainless steel cylindrical pipe 26 is cut 31 at about 45 degrees (Fig. It is also preferable to make an elbow by rounding it and welding two pieces like this together.

Furthermore, as shown in FIG. 6, it is also possible to manufacture an elbow by plastic working a large recess 33, cutting it at a 2f[lil cut surface, and joining it.

Next, the manufacturing method of the cap nut 9 is shown in FIG. 7. As shown in FIG. 2 (1), a stainless steel pipe cut into short lengths is used as the material 34, and the inner circumferential opening ring edge of one end surface is cut in advance in the same manner. Figure (II
), chamfer 35 (machining), then (
I[r] has difficulty in cold forging, so the corners are made hexagonal and one end (on the right side of the figure) is reduced in diameter by 3.
6. Next, as shown in the same figure (rV), the female screw portion 8, the inclined portion 20, the hole 19, etc. on the inner circumferential surface may be machined.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and it goes without saying that the design can be changed in various ways. For example, the joint body 4 may be made of various types of piping such as a cheese, a cross, a male and female socket, a reducing elbow, a reducing nipple, etc. It is also preferable that the shapes are similar.

〔Effect of the invention〕

According to the above configuration, the pipe joint is assembled by providing the flare portion 5 at the end portion 3 of the connected vibro, so the number of parts is small, the structure is simple, and it can be easily assembled in a detachable manner. Furthermore, since it is a stainless steel pipe joint, it can be used as a pipe joint for heat exchangers and the like that require corrosion resistance, and has the remarkable effect of shortening the assembly work compared to conventional stainless steel pipe joints.

[Brief explanation of drawings]

FIG. 1 is a half-cut sectional view showing one embodiment of the present invention, FIG. 2 is a sectional view of each component, FIG. 3 is a half-cut sectional view showing another embodiment, and FIGS. FIG. 6 is a simplified explanatory diagram showing the manufacturing method of the joint body, and FIG. 7 is an explanatory diagram showing the manufacturing method of the cap nut. 3... End part, 4... Joint body, 5... Flare part,
6... Connected pipe, 7... Seal member.

Claims (1)

[Claims] 1. A stainless steel connected pipe 6 having an enlarged conical flare portion 5 formed on its end surface, a tapered short tubular sealing member 7 that is in close contact with the inner surface of the flare portion 5, and an end portion 3.
A pipe joint characterized in that it comprises a stainless steel joint body 4 which is formed into a tapered shape and comes into close contact with the inner surface of the seal member 7.