JPH07237662A - Pipe end-protecting tool and method for formation thereof - Google Patents

Abstract

PURPOSE:To form a ring reinforcement into an arbitrary shape and facilitate the reuse of the material after use, in a pipe end protecting tool having its synthetic resin-made cylindrical member reinforced with a metal-made ring reinforcement. CONSTITUTION:A cylindrical member 1 and a ring reinforcement 2 are made freely attachable and detachable and they are engaged with each other and are fastened together with machine screws 10. In this structure, since the ring reinforcement 2 is fixed by the machine screws, the shape of the ring reinforcement can be freely designed. After use, the machine screws 10 are removed to separate the cylindrical member 1 and the ring reinforcement 2, each of which is then recycled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe end protector for protecting a screw at a pipe end and a method for forming the same.

[0002]

2. Description of the Related Art Pipes having a screw at the pipe end such as an oil well pipe or a joint thereof are equipped with a pipe end protector at the end to prevent the screw from being damaged during transportation.

As shown in FIG. 6, a conventional tube end protector is as follows.
A screw thread 23 to be screwed with a screw at a pipe end is formed on an inner peripheral surface or an outer peripheral surface of a cylindrical member 21 made of synthetic resin.
In order to reinforce the strength of No. 1, a metal reinforcing ring 22 is fitted on the peripheral surface of the cylindrical member 21.

The reinforcing ring 22 is arranged so as not to come off from the cylindrical member 21 due to vibration or shock during transportation.
It is forcibly fitted to the peripheral surface of No. 1 with a large interference and is fixed integrally, and in order to increase the fitting force, the length of the reinforcing ring 22 is the entire peripheral surface of the cylindrical member 21 without the thread 23. It is formed in a size that almost covers the.

[0005]

By the way, when the pipe such as the oil well pipe is transported to the destination, the pipe end protector is detached from the pipe and used, but in the used state. However, since the reinforcing ring 22 remains inside the protector, it is impossible to crush the protector to reduce its shape at the time of disposal, and there is a problem that the space for disposal becomes large. Further, even when the material of the used pipe end protector is reused, since the cylindrical member 21 and the reinforcing ring 22 cannot be integrated and separated, there is a problem that recycling of synthetic resin or metal is difficult.

Further, as described above, the conventional reinforcing ring 22 is used.
Is required to be as large as possible in order to obtain a large fixing force by forced fitting, and is usually formed to cover the entire peripheral surface of the cylindrical member 21.
There is a problem that the degree of freedom in designing the shape of the reinforcing ring is small and the material cost is high as a whole. However, actual reinforcement of the pipe end protector may be sufficient if it is performed only on the exposed portion of the cylindrical member 21 exposed from the pipe, and the restriction on the length dimension for fixing as described above is due to the reinforcement ring 22. There is a problem that the shape of is larger than the shape required for reinforcement.

Therefore, the present invention provides a pipe end protector which solves the above-mentioned problems, allows the shape of the reinforcing ring to be set arbitrarily, and enables reuse of constituent materials after use, and a method of forming the same. It is intended to be provided.

[0008]

In order to solve the above-mentioned problems, a pipe end protector of the present invention is a screw for screwing a screw at a pipe end to an inner peripheral surface or an outer peripheral surface of a cylindrical member made of synthetic resin. A mountain is formed, a metal reinforcing ring is fitted on the surface of the cylindrical member having no thread, and the reinforcing ring and the cylindrical member are detachably fixed by a connecting tool.

It should be noted that the connecting member may be a screw, and the screw introduction hole of the screw of the cylindrical member may be formed in advance.

Further, according to the forming method of the present invention, a metal-made reinforcing ring is fitted to a cylindrical member made of synthetic resin having a screw thread on the inner peripheral surface or the outer peripheral surface, and the cylindrical member and the reinforcing ring are attached and detached. It was a method of fixing with a free connecting tool.

In the above-mentioned forming method, it is possible to lock the connector by pushing it into the cylindrical member in a heated state and melting a part of the cylindrical member by the heat.

[0012]

When the pipe end protector is configured as described above, the cylindrical member and the reinforcing ring can be separated by removing the connecting tool after use, so that the material can be easily reused.

Further, since it is not necessary to fix the reinforcing ring by forcibly fitting, the length of the reinforcing ring is not restricted by securing the fixing force, and the reinforcing ring can be formed in any shape.

[0014]

1 and 2 show a pipe end protector of an embodiment. A cylindrical member 1 made of synthetic resin is provided with a screw thread 3 that is screwed into a screw at a pipe end on an outer peripheral surface, and a large diameter portion 4 exposed from a pipe in a mounted state is provided at one end. Has been. A plurality of screw introduction holes 5 for the screws 10 are formed on the end surface of the large diameter portion 4. The screw introducing holes 5 are formed at the same time when the cylindrical member 1 is formed by injection molding or the like.

The reinforcing ring 2 made of metal is a cylindrical member 1.
A cylindrical portion 7 to be inserted into the inner hole 6 and a flange portion 8 that comes into contact with the end surface of the large diameter portion 4, and a plurality of through holes 9 into which the screws 10 are inserted are formed on the surface of the flange portion 8. ing.

The outer diameter of the cylindrical portion 7 is the same as the diameter of the inner hole 6 of the cylindrical member 1 or slightly larger so as to fit with a slight interference. It can be inserted and removed freely with a small force.

To assemble the above-mentioned pipe end protector, the cylindrical portion 7 of the reinforcing ring 2 is inserted into the cylindrical member 1 and the screw 10 is screwed into the screw introducing hole 5 from the through hole 9 to form the reinforcing ring 2 and the cylinder. The member 1 is fixed. In this case, since the screw introduction hole 5 is formed in the cylindrical member 1 in advance, the screw 10 can be easily screwed in, and the screwing can be securely performed.

When the pipe end protector is used up, the screw 10 is removed and the cylindrical member 1 and the reinforcing ring 2 are separated. Thereby, the constituent materials of the cylindrical member 1 and the reinforcing ring 2 can be easily reused. Also, the separated reinforcing ring 2
Since it can be crushed to reduce the volume, the storage and transportation space can be reduced.

FIG. 3 shows a second embodiment in which the reinforcing ring 2 is
The cylindrical member 1 is formed so as to cover only the inner and outer diameter surfaces and the end surface of the large diameter portion 4 of the cylindrical member 1.

As described above, even if only the large diameter portion 4 of the cylindrical member 1 exposed from the pipe is reinforced with the reinforcing ring 2, the protective tool can be prevented from being deformed when an external force is applied, and the screw at the pipe end can be effectively used. Can be protected.

Further, in the third embodiment shown in FIG. 4, the shape of the reinforcing ring 2 is further reduced and formed so as to cover only the end surface and the outer diameter surface of the large diameter portion 4.

On the other hand, FIG. 5 shows a fourth embodiment, in which a thread 3 is formed on the inner peripheral surface side of the cylindrical member 1 so that the reinforcing ring 2 covers the outer peripheral surface of the cylindrical member 1. Installed on.

Further, the screw 10 is not formed in advance on the end surface of the cylindrical member 1, and the heated screw 10 is attached to the reinforcing ring 2
It is pushed directly into the cylindrical member 1 through the through hole 9. When the screw 10 heated in this way is pushed in, the synthetic resin of the cylindrical member 1 is melted by the heat and the screw 1 invades.
Molten resin enters the 0 screw thread. When the resin that has entered is solidified along the shape of the screw thread when cooled, the movement of the screw thread is stopped and the screw 10 is prevented from coming out. Further, since the shape of the screw thread is retained inside the synthetic resin, when the screw 10 is rotated in the loosening direction, it can be pulled out from the cylindrical member 1 by the guide of the screw thread.

In this method, it is only necessary to push the screw 10 into the cylindrical member 1, and it is not necessary to rotate and screw it in, so that the assembling work can be performed efficiently in a short time.

Even in the structure in which the thread 3 is provided on the inner peripheral surface side of the cylindrical member 1 as shown in FIG. 5, only the vicinity of the end of the cylindrical member 1 is provided with the reinforcing ring 2 as shown in FIG. 3 or 4. You may make it cover.

In each of the above embodiments, the cylindrical member 1
And the screw 10 is shown as a connecting tool of the reinforcing ring 2, but in addition,
A rivet or the like can be used, and any tool that can be easily fixed by a mechanical operation can be used as the connector.

[0027]

As described above, according to the present invention, the cylindrical member and the reinforcing ring are detachably fixed to each other by the connecting tool, and both of them can be separated, so that the material after being used can be easily reused and stored. There is an advantage that the space for transportation can be greatly reduced.

Further, since the degree of freedom in designing the shape of the reinforcing ring is increased, it becomes possible to form the shape of the reinforcing plate in accordance with the portion required for the reinforcement, and the material cost can be reduced.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a pipe end protector of a first embodiment.

FIG. 2 is a vertical sectional view of the above.

FIG. 3 is a vertical sectional view of a second embodiment.

FIG. 4 is a vertical sectional view of a third embodiment.

FIG. 5 (a) is a state before mounting a screw of the fourth embodiment,
(B) is a vertical cross-sectional view showing the state after the screws are attached.

FIG. 6 is a vertical sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical member 2 Reinforcement ring 3 Screw thread 4 Large diameter part 5 Screw introduction hole 6 Internal hole 7 Cylindrical part 8 Flange part 9 Through hole 10 Screw

Claims (4)

[Claims] 1. A synthetic resin cylindrical member is provided with a screw thread on an inner peripheral surface or an outer peripheral surface to be screwed with a screw at a pipe end, and a metal reinforcing ring is formed on the surface of the cylindrical member without the screw thread. A pipe end protector in which the reinforcing ring and the cylindrical member are detachably fixed by a connecting tool. 2. The pipe end protector according to claim 1, wherein the connecting member is a screw, and a screw introduction hole for the screw is formed in the cylindrical member in advance. 3. A metal-made reinforcing ring is fitted to a synthetic resin cylindrical member having an inner peripheral surface or an outer peripheral surface provided with a screw thread, and the cylindrical member and the reinforcing ring are fixed to each other by a detachable connector. A method for forming a pipe end protector. 4. The method for forming a pipe end protector according to claim 4, wherein the connecting tool is pushed into the cylindrical member in a heated state, and a part of the cylindrical member is melted by the heat to lock the connecting tool.