JPH0669595U - Protective structure for screw connection in FRP hoist pipe - Google Patents

Abstract

(57) [Abstract] [Purpose] A hot water pipe and an air pipe that prevent corrosion due to the quality of the hot spring water and wear due to vibrational contact occurring at the time of hot water at the screw connection part of the FRP hot water pipe for the hot spring and the air one pipe. The purpose is to extend the life of the. [Structure] After tightening the screw connection portion of the FRP pumping pipe or the air pipe, a thermoplastic heat shrink tube is inserted into the entire screw connection portion, and heat is applied to shrink and fix.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a protective structure for a screw connection portion in a hot water well pumping pipe and an air pipe used in a hot spring well or the like.

[0002]

[Prior art]

 For example, the connection part of the hot water well pumping pipe and air pipe made of reinforced plastic such as FRP is molded with a screw type, or machined male and female screws are used, and a pipe wrench is used. Connect the outside of the connection screw part and tighten it while rotating it, or use a plastic pipe and socket that does not form a screw, and connect it while fixing it with an adhesive, without connecting the contact part and connecting directly to the hot spring well. The method of taking it down is adopted.

[0003]

[Problems to be solved by the device]

 By the way, most of the hot springs have a quality that causes corrosion such as sulfuric acid gas and salts. Therefore, the iron pipes used to pump this hot spring often corrode in 1 to 2 months and become unusable.

As a countermeasure for this, recently, many wells use a reinforced plastic pipe having excellent corrosion resistance. However, the glass fiber used for the reinforced plastic pipe is composed of a sulfuric acid component or hydrofluoric acid contained in the spring quality. If such a material directly contacts the glass fiber, the glass fiber will be corroded and its strength will be reduced, making it unusable.

As a protection method, a corrosion resistant layer is provided on the inner and outer surfaces of the pipe to protect it, but since the screw connection part is tightened with a pipe wrench or the like, the protective layer is damaged and the fiber is exposed, or the pipe is exposed. However, there was a problem in that it was directly affected by the corrosive components because the end face of was exposed.

[0006] Furthermore, in the hot water pipe and the air pipe that are piped in the hot spring well, the inner surface of the pipe and the projection of the screw connection portion may come into contact with each other due to the vibration during operation, resulting in severe wear and perforation in a short time. .

The present invention has been made in view of the above circumstances, and extends the life of the FRP hoisting pipe and the air pipe by increasing the corrosion resistance of the screw connection portion of the FRP hoisting pipe and the air pipe. It is intended to provide a protective structure for a screw connection part in a FRP lift pipe.

[0008]

[Means for Solving the Problems]

 In order to achieve the above object, the protective structure of the screw connection part in the FRP hoisting pipe according to the present invention is such that the female screw air pipe and the male screw air pipe disposed in the FRP hoisting pipe are fastened and fixed at the screw connecting part. In addition, a thermoplastic heat-shrinkable tube is fitted on the outer surface of the screw connection part and heat-treated to shrink-fix the screw connection part with the heat-shrink tube.

[0009]

[Action]

 As is clear from the above structure, the screw connection portion is always scratched by the teeth of the pipe wrench at the time of tightening and the glass fiber portion is exposed. Also, since a protective layer cannot be provided on the end surface of the connecting portion unlike the inside and outside surfaces of the pipe, the fiber is also exposed at this portion and is directly exposed to corrosive components.

By coating such a portion with a thermoplastic heat-shrinkable tube that is stable against the corrosive component, it is possible to prevent the corrosive component from entering and protect the defective portion.

[0011] Furthermore, the hoisting pipe and the air pipe vibrate during operation, and the projections at the connecting portion constantly come into contact with each other. Therefore, in the case of the same material, wear occurs in both cases. Therefore, since the elastic thermoplastic heat-shrinkable tube made of a different material is provided as a cushioning material in the screw portion in contact with the screw, the tube is not worn and can be used for a long time.

[0012]

【Example】

 Hereinafter, a protective structure of a screw connection portion of an FRP lift pipe according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of an FRP hoisting pipe according to the present invention, showing the structure of the hoisting pipe used in the airlift method for hot spring wells. Further, an air pipe connecting the female screw air pipe 3 and the male screw air pipe 4 is arranged in the pouring pipe 2.

Then, compressed air is sent from the air pipe, air enters the hot spring source from the tip of the air pipe, and the air enters the hot spring source, so that the specific gravity of the hot spring becomes lighter, and the difference in specific gravity from the surrounding hot springs The principle is that the hot water from the hot spring is pushed up in the hoisting pipe 2.

Further, the hoisting pipe 2 and the air pipes 3 and 4 are made of reinforced plastics that are not easily corroded by the corrosive components contained in the hot spring, and the female screw air pipe 3 and the male screw air pipe 4 are Is connected by tightening the screw connection part with a pipe wrench.

By the way, the feature of the present invention relates to the protective structure of the screw connection portion, in which the thermoplastic heat-shrinkable tube 5 is set so as to cover the outer surface of the screw connection portion, and the heat treatment is applied to the screw heat-shrinkable tube 5. The structure is such that it contracts and adheres to the outer surface of the connection portion.

That is, a thermoplastic heat-shrinkable tube 5 having an inner diameter larger than the outer diameter of the screw connection portions of the air pipes 3 and 4 by 1 to 10 mm is prepared, and cut by 10 to 50 mm longer than the screw connection portions, Insert into either the female screw air pipe 3 or the male screw air pipe 4.

Then, after the female screw air pipe 3 and the male screw air pipe 4 are fastened and connected with a pipe wrench or the like, the inserted thermoplastic heat shrink tube 5 is attached to the screw portion, and a gas burner, torch lamp, steam Heat shrink with a heat source such as. In this way, connect and pipe in sequence.

In this way, by protecting the threaded portions of the FRP hoisting pipe 2 and the air pipes 3 and 4, the scratches generated at the time of connection and the exposed glass fiber portion of the pipe end face do not directly contact the corrosive components. The pumping pipe 2 and the air pipes 3 and 4 can be stably used for a long period of time.

Further, at the same time, even when the inner surface of the tube and the screw protrusion contact wear due to vibration during use, the elasticity of the thermoplastic heat-shrinkable tube 5 does not cause wear and can be stably used.

The material of the thermoplastic heat-shrinkable tube may be appropriately selected from thermoplastic resins such as fluororesin, polypropylene resin, vinyl chloride resin and polyethylene resin.

When removing the thermoplastic heat-shrinkable tube 5, the air tubes 3 and 4 can be easily removed by cutting with a cutter knife and rotating the screws of the air tubes 3 and 4. .

[0023]

[Effect of device]

 As described above, the present invention has the following special effects by covering and protecting the plastic connection pipes of the reinforced plastic pipe and the air pipe with the thermoplastic heat-shrinkable tube. (1) Protect the glass fiber exposed from the damaged part during screw connection from the corrosive spring component, and also protect the glass fiber whose end face is exposed from the corrosive spring component. (2) Protects from corrosive spring components against vibration during pumping.

Therefore, the protective effects of (1) and (2) have the effect of significantly extending the life of the reinforced plastic pumping pipe.

[Brief description of drawings]

FIG. 1 is an FR showing a protective structure of a screw connection portion according to the present invention.
It is sectional drawing which shows the structure of a P hoist pipe.

[Explanation of symbols]

1 ... Casing pipe 2 ... Lifting pipe 3 ... Female screw air pipe 4 ... Male screw air pipe 5 ... Thermoplastic heat shrink tube

Claims (1)

[Scope of utility model registration request] 1. A female screw air pipe and a male screw air pipe disposed in a FRP hoist pipe are fastened and fixed at a screw connection portion, and a thermoplastic heat shrinkable tube is fitted on the outer surface of the screw connection portion. A protective structure for a screw connection part in an FRP hoist pipe, wherein the screw connection part is contracted and fixed by a heat-shrinkable tube by heat treatment.