JPH02190695A - Joint sleeve - Google Patents

Abstract

PURPOSE:To connect tubes made of a polymer material with high precision by sealing a linear heating element folded into two and wound in a spiral shape in parallel in no contact with each other in a thermoplastic polymer material layer molded into a hollow cylinder. CONSTITUTION:A coated linear heating element 1 is folded into two and wound in a spiral shape closely in parallel without crossing from the small diameter side of a conical-diameter roller 2. Both ends of the large diameter side of the roller 2 are connected to a storage battery and excited then quickly cooled to obtain a joint sleeve 3. This sleeve 3 is sealed in a polybutene layer integrally melted by heating so that a nichrome wire is arranged at a uniform interval in no contact with each other. This sleeve 3 is inserted in the coupling section between tube end sections to be connected, the linear heating element 1 is excited, the coating is softened or melted, and connection sections are integrally melted.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a joint sleeve for piping construction, etc.
It relates to methods of making and using the same.

[Conventional technology]

Polymer materials such as various synthetic resins and synthetic rubbers are used in place of metals or ceramics because they are easy to mold, have excellent water and chemical resistance, and are lightweight. The field is rapidly expanding. for example,
A large number of polymer materials are already being used in the fields of pipes such as iron pipes, lead pipes, steel pipes, stainless steel pipes, clay pipes, and ceramic pipes, as well as the fittings that connect these pipes, as well as valve plugs. .

Currently, in order to connect pipes, fittings, valve plugs, etc. made of polymeric materials, especially thermoplastic resins or rubber, to prevent leakage, etc., and to enable smooth piping construction. , each connection must be tightly sealed. However, adhesives suitable for a limited number of polymeric materials such as ABS resin, polyvinyl chloride, and polystyrene have been developed, and if they are applied to the joint and cured, Although it can easily serve the purpose, suitable adhesives have not yet been obtained for many materials such as polyolefins, polyamides, polyacetals, and fluorine-containing resins.Therefore, polymer materials without such adhesives have been developed. For this purpose, a method has been adopted in which the parts to be connected are softened or melted by an external heating method (flame or tube furnace, etc.), and then joined all at once without cooling, and then cooled and solidified. However, with such external heating methods, it is extremely difficult to uniformly heat the material and to maintain the appropriate softening or melting state, and good results cannot be obtained.

[Problems to be Solved by the Invention] As described above, in the conventional technology, polymer pipes can be stably worked even in particularly unstable environments such as construction sites. There is a problem in that a method for connecting with high accuracy has not yet been developed, and solving this problem has been an issue.

[Means to solve the problem]

In order to solve the above-mentioned problems, this invention has been developed to form a linear heating element that is bent in two and spirally wound in parallel without contacting each other into a hollow cylindrical body. Means for forming a sleeve for a joint enclosed in a layer of thermoplastic polymer material, a linear heating element coated with a thermoplastic polymer material is bent in two, and the bent 2
The wire-like heating elements covered by the book are wound spirally around the surface of the roller while being parallel and in close contact with each other. Electricity is applied to the wire-like heating elements to fuse the adjacent coverings together, and then the book is cooled and solidified. and removing it from the roller to produce the joint sleeve, which is a hollow cylindrical body. The outer surface of the small-diameter pipe and the inner surface of the large-diameter pipe are fused and integrated by applying electricity to the linear heating element to soften or melt the covering, that is, the sleeve for shinning, and to fuse and integrate the outer surface of the small-diameter pipe and the inner surface of the large-diameter pipe. This method adopts the method of connecting the types. These details will be described below.

First, the piping of this invention includes not only pipes, but also various types of joints used for long piping, changing the piping direction, changing the pipe diameter, installing branch pipes, and valve plugs such as cocks and pulp. included. Therefore, these connections include not only pipes, but also connections between pipes and joints, pipes and valve plugs, and the like.

Next, the thermoplastic polymer used in the present invention may be one for which a suitable adhesive has already been developed or one that has not yet been developed.

The thermoplastic polymer material used for the sleeve for the bow tie should be of the same type as the material of the pipes to be connected.
Needless to say, it is desirable to have a high affinity.

Furthermore, the hollow cylindrical body of the present invention must have an inner and outer diameter that fits the outer surface of the small-diameter pipe end to be connected and the inner surface of the large-diameter pipe end. It is preferable that each pipe end and the hollow cylindrical body be tapered to the same degree, since this makes the fitting operation extremely easy. Therefore, when forming a hollow cylindrical body, by using a tapered conical roller, more preferably a roller with a releasable surface, a tapered cylindrical body can be easily obtained. It also becomes easier to remove the molded product from the roller.

In addition, in this invention, when winding the coated linear heating element around the roller, it is of course possible to temporarily fix the bent portion in two on the roller, and the specific method is not particularly limited. However, hooking it on a protrusion (pin), for example, is one method that does not reduce work efficiency.

Furthermore, the current flow carried out in the method of the present invention does not cause any trouble whether AC or DC current is used.

[Effect]

Inside the joint sleeve of this invention, linear heating elements bent in half are buried in a spiral shape at regular intervals without short circuiting, and both ends of the heating elements can be exposed in close proximity. . Therefore, if both ends of the linear heating element are exposed on the end surface that appears outside even after the joint sleeve is joined, connection to the power source is easy.
Even if the exposed part of the heating element is cut off after use, the cut surface will not come into contact with the fluid inside the tubing, and the bent part is also covered with thermoplastic polymer material from the beginning. Therefore, even if the heating element is sealed deep inside the joint of the pipes, there is no fear of corrosion since the heating element does not come into direct contact with the fluid inside the pipes.

〔Example〕

A coated linear heating element 1 made of nichrome with a diameter of 0.4 m and polybutene coated with a thickness of 0.4 m is bent in half to form a small diameter roller 2 with a conical diameter (Taber 1/30) as shown in Fig. 1. Wrap the roller 2 in a spiral shape without crossing it from the sides (parallel to each other and in close contact with each other).
(not shown) and energized with 1.5A for 2.5 minutes.
Immediately leave it to cool, and then
), large diameter (outer diameter 25.6m, inner diameter 22.8m+)
A joint sleeve 3 having a length of 18 cm was obtained. As shown in Fig. 2, this joint sleeve 3 has a structure in which nichrome wires are enclosed in a polybdenum layer that is fused and integrated by heating and arranged at equal intervals without touching each other. there were. Then, a polybutene socket 4 as shown in FIG. 3 is prepared 1, a joint sleeve 3 is placed over the end of a polybutene tube 5, and the joint sleeve 3 is fitted into the socket 4 as shown in FIG. While pushing each joint lightly, electricity was applied to the nichrome wire of the joint sleeve 3 at 1.5 A for 2.5 minutes using the same storage battery as described above. As a result, the joint sleeve 3 was completely softened, so the electricity was turned off and the fitting portion was cooled while being lightly pressed, and the socket 4 and tube 5 were fixed together and did not move. When we cut the connection part to check the condition of the fused part, we found that the joint sleeve 3, socket 4, and tube 5 were completely fused together, with no boundaries visible at all, and the nichrome wire was almost completely fused. They were arranged in an orderly manner at even intervals and were sealed with a layer of polybutene, and no cavities were found that could lead into the tube.

〔effect〕

As described above, the joint sleeve of the present invention is easy to manufacture and use, and moreover,
Because it is highly accurate, it is possible to achieve effects not seen with conventional technology, even in work sites with extremely unstable environments. Therefore, problems such as leakage due to poor connections and the like will not occur, and the applications of tubing made of polymeric materials will naturally expand, so it can be said that the significance of this invention is extremely large.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing the coated wire heating element wrapped around the roller surface in an embodiment of the present invention, Fig. 2 is a longitudinal cross-sectional view showing the structure of the joint sleeve, and Fig. 3 is the same. FIG. 4 is a vertical cross-sectional view showing the socket, and FIG. 4 is a vertical cross-sectional view showing the fitted state of the pipe, the joint sleeve, and the socket. 1...Coated linear heating element, 2...Roller, 3...Joint sleeve, 4...
Socket, 5...tube.

Claims (3)

[Claims] (1) A linear heating element that is bent in two and spirally wound in parallel without touching each other is inside a thermoplastic polymer material layer formed into a hollow cylindrical body. A joint sleeve characterized by being enclosed in a. (2) A linear heating element coated with a thermoplastic polymer material is bent in half, and while the two bent coated linear heating elements are parallel to and in close contact with each other, a spiral is applied to the surface of the roller. The method of claim 1 is characterized in that the linear heating element is wound in a shape, electricity is applied to the linear heating element, adjacent coatings are fused together, and then cooled and solidified to be removed from the roller to form a hollow cylindrical body. A method for manufacturing a joint sleeve according to scope 1. (3) The joint sleeve according to claim 1 is interposed between the fitting portion of the small-diameter pipe end and the large-diameter pipe end, and the linear heating element is energized to make the joint sleeve A method for connecting pipes made of polymeric material, characterized by softening or melting the material to fuse and integrate small-diameter pipes and large-diameter pipes.