JP3240690U - Rubber expansion and contraction flexible tube fittings. - Google Patents

Abstract

[Problem] The current expansion and contraction flexible pipe joint is a double-tube type slide-type expansion and contraction flexible pipe joint that includes a sleeve having a slightly larger diameter than the mating joint, a spigot pipe that is inserted into the sleeve and joined to the mating joint pipe, and these two. It consists of a specially shaped rubber ring that seals the gap between two pipes. There is a problem that the surface length is long and the weight is heavy, and the handling is not satisfactory, so it is necessary to reduce the weight. In addition, as a countermeasure against corrosion current, an insulating rubber layer is provided on the contact portion to avoid contact. SOLUTION: A steel pipe 3 having a diameter slightly larger than that of a mating joint and having equal strength or more is subdivided, and a composite of rubber and fibers wound at a bias of 45° that is easily deformable is interposed as a reinforcing layer 4 to create a plurality of deformed parts. It is easy to deform and can realize weight reduction. Also, providing the insulating rubber layer 1 on the flange portion 2 serves as a countermeasure against corrosion current. [Selection drawing] Fig. 2

Description

TECHNICAL FIELD The present invention relates to a rubber expansion/contraction flexible pipe joint for absorbing displacement of a pipeline.

The current expansion and contraction joint is a double-pipe slide-type expansion and contraction flexible joint. It consists of a specially shaped rubber ring that seals the gap.

There is a problem that the face length is long and the weight is heavy, so the situation is not fully satisfactory.

There is a problem that it is difficult to deal with large deformation because the range of motion that can be deformed is small.

In the case of connecting a stainless steel expansion pipe and a steel pipe, a corrosion cell is formed between the damaged paint coating of the steel pipe of the stainless steel expansion pipe that is not insulated, creating an environment where galvanic corrosion, in which the steel pipe corrodes, is likely to occur. ing.

https://www. maff. go. jp. > sutumane. koukan. attach. pdf. koukan-8 Chapter 2 Types of corrosion and their characteristics 2-12 (3) Galvanic corrosion of dissimilar metals

In the above expansion flexible joint, a long steel pipe surface length is required to absorb the deformation, which increases the weight and makes it difficult to handle.

It was difficult to handle because a long steel pipe surface length was required to absorb eccentricity and bending deformation.

Corrosion current countermeasures as corrosion countermeasures are not fully satisfactory.

Two types of steel pipes with different outer diameters with the same strength or higher are used for the joints, and the surface length is subdivided to form an inner ring and outer ring structure.

The pipe lengths of the inner and outer rings of the steel pipes used in the joint are arranged so that they can withstand internal and external pressure even when deformed during expansion and contraction.

The groove shape of the deformed part on the inner surface and the outer surface, and the reinforcing cloth wrapped around the bias of 45° facilitates the expansion and contraction deformation in all directions.

The vinylon and polyester fibers used as the reinforcing layer can maintain stable durability because they are covered with rubber.

The inner ring, outer ring, and mouthpiece are integrated with reinforcing fabric and rubber, and sufficient pressure resistance can be obtained through vulcanization.

By designing and manufacturing a mouthpiece in the same shape as the mating pipe connecting part, it is possible to connect to all types of pipes.
Mating pipes include steel pipes, Hume pipes, ductile cast iron pipes, and stainless steel pipes.

As described above, since the inner ring and the outer ring having the same strength are integrated with the ferrule suitable for the mating pipe connection steel pipe, sufficient strength against internal pressure and external pressure can be obtained.

Due to the easily deformable structure described above, it can absorb large amounts of displacement due to expansion, contraction, eccentricity, and bending.

Good follow-up to pipeline displacement, good damping effect on vibration and noise transmission.

Front view, left side view, right side view of rubber expansion and contraction flexible tube joint A-B sectional view of rubber expansion and contraction flexible pipe joint in normal state, enlarged view of C part A-B cross-sectional view of rubber expansion/contraction flexible tube joint during elongation deformation, enlarged view of C part A-B cross-sectional view of contraction deformation of rubber expansion/contraction flexible pipe joint, enlarged view of C part A-B sectional view of eccentric + elongation deformation of rubber expansion and contraction flexible pipe joint, enlarged view of C part

This invention uses a base, inner ring, outer ring, vinylon, polyester fibers, and properly blended rubber materials.

The material of the inner surface rubber used for water supply equipment and water supply pipes is ethylene-propylene rubber (EPDM) which is excellent in weather resistance and water resistance and conforms to JISK6353 class III for water supply. 50 PHR of Mitsui Chemicals' raw material EPT4070 is used as a reinforcing material, and 27 PHR of SEAST#3 is used as a main compounded rubber to ensure quality with a hardness of 60 degrees. .

Chloroprene rubber (CR), which is excellent in weather resistance, is used for the jacket rubber of rubber expansion and contraction flexible joints. Denka chloroprene rubber 75 PHR of raw material M-120 and 27 PHR of reinforcing material Asahi #35 are used as the main raw materials to ensure quality with a hardness of 60 degrees.

The insulating rubber layer is made of chloroprene rubber (CR), which has excellent weather resistance. Denka chloroprene rubber 40 PHR of raw material S-41 and 50 PHR of reinforcing clay are used as main raw materials. , 000 volts.

After forming the above materials on the steel pipe-shaped core structure on the inner surface side according to the design specifications, the cloth tape is wound around and fixed, and vulcanization is performed to complete the product.

Prepare materials to drawing specifications. Adhesive is applied to metals such as the mouthpiece, inner ring, and outer ring after shot blasting and dried.

Insulating rubber is attached to the outer periphery of the flange, and the insulating rubber layer is molded.

Reinforcing cloth, mouthpiece, inner ring, and outer ring are pasted on the inner rubber and molding work is performed.

After completion of molding, cloth tape is wrapped around the entire product to fix it, the flange is fixed in the mold, and the product is placed in a vulcanizing pot with steam heat as a heat source for 2 to 10 hours depending on the product size to perform the vulcanization operation, and the kneaded rubber is removed from the plastic material. It can be changed into an elastic body to obtain performance as rubber.

After vulcanization, the product is tested for normal dimensions, expansion, contraction, eccentricity, and torsion to confirm quality.

Used to absorb displacement and prevent damage to water and sewage pipelines.

It is used as a pipeline for civil engineering and building equipment piping as a countermeasure against galvanic corrosion of dissimilar metals.

REFERENCE SIGNS LIST 1 insulating rubber layer 2 base flange 3 steel pipe 4 reinforcing fiber layer 5 outer rubber layer 6 fixing wire 7 fixing ring 8 reinforcing outer ring 9 inner rubber layer 10 reinforcing inner ring

Claims (5)

In order to withstand the expansion, contraction, eccentricity, bending, and internal and external pressure of pipelines caused by ground subsidence, etc., it is necessary to install expansion and contraction flexible pipe joints at key points in the pipeline. As a joint that can expand and contract based on the inner diameter that matches the mating pipe, an inner ring that is slightly larger than the inner diameter and an outer ring that is slightly larger than the inner ring are made of rubber, and reinforced fiber is wrapped around the bias at 45 degrees to form an integrated rubber expansion and contraction flexible pipe joint. . 2. The rubber expansion and contraction flexible tube joint according to claim 1, wherein the face-to-face length is shortened and the joint is easily deformed by dividing it into an inner ring and an outer ring. 3. The rubber expansion/contraction flexible tube joint according to claim 1 or 2, wherein double widths of the inner ring and the outer ring are set to a width corresponding to the required deformation performance. Corrosion current can be prevented by providing an insulating rubber layer on the contact part of the pipe as a countermeasure against macrocell corrosion that occurs when the points with different potential differences are fixed at a certain distance, or against corrosion current such as contact corrosion between steel pipes and stainless steel expansion pipes. 4. The rubber expansion/contraction flexible tube joint according to claim 1, 2, or 3, which has a structure that stops the corrosion to prevent corrosion. In order to integrate with the connecting part of the mating pipe, the outer circumference of the inner ring and the outer ring is reinforced by wrapping a reinforcing cloth at a bias of 45°, and the inner end of the inner ring part of the connecting part of the mating pipe is a carbon steel pipe for machine structure. 5. The rubber expansion/contraction flexible tube joint according to claim 1, 2, 3, or 4, wherein the reinforcement ring is welded, and the reinforcement cloth and the steel pipe are fixed by winding a wire circumferentially.

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