JPH0717907Y2 - Concrete pipe joint structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a joint structure of a concrete pipe.

<Prior art> When inserting and connecting each concrete pipe, a rubber ring is press-fitted into the connection gap. , There may be a place where it hits when it is inserted, and it may partly shift or turn over, and it may not be pressed into the prescribed position normally. Especially, as seen in the propulsion method, such a problem remarkably occurs when a machine such as a jack is used for inserting with pressure. Therefore, recently, it has been attempted in a factory to attach a rubber ring to a predetermined position of a concrete pipe by using an adhesive so as to prevent the problem from occurring.

<Problems to be solved by the invention> However, when the rubber ring to be adhesively fitted is made of water-expandable rubber, the rubber ring will expand due to water during standby during shipment or during transportation, and the insertion and connection will be performed. There is a challenge to make it difficult. The present invention is intended to solve such a problem.

<Means for Solving the Problems> The present invention uses a two-layer extruder to form a main body made of water-expandable rubber and a gasket member formed by coating the outer surface except one surface of the main body with a peelable waterproof film. Extruded, the gasket member was bent inward on one surface of the non-coating to make a ring by vulcanizing connection between the end faces of the main body, and fitted to the outer surface of the end of the concrete pipe with an adhesive. However, the waterproof film is peeled off immediately before the connection.

<Operation> The present invention is a large- and small-sized water-inflatable rubber main body and a gasket whose outer surface excluding the inner surface is covered with a waterproof film is extruded and molded using a two-layer extruder, and this is inserted into a concrete pipe. The ends are fitted with an adhesive and carried to the construction site, and the waterproof film is peeled off and inserted and connected immediately before the construction on site. In particular, even in a propulsion method in which pressure is applied by a machine, the gasket is prevented from being turned over or displaced.

<Examples> A two-layer extruder (not shown) is used to extrude a water-expandable rubber main body 1 and a gasket member 4a formed by coating the outer surface of the main body 1 excluding one surface 2 with a waterproof film 3. Mold.

The main body 1 made of water-swellable rubber is based on a blend of isoprene rubber (1R) and styrene-butadiene rubber (SBR), and a proper amount of a super absorbent polymer is added thereto. Further, as the waterproof film 3, nitrile butadiene rubber (NB
R) or silicone rubber is used.

As described above, the waterproof film 3 expands and contracts as the main body 1 expands and contracts, and can be easily peeled off.

Further, the waterproof film 3 is colored in a conspicuous color such as red or yellow so that it can be easily peeled from the colored boundary and no peeling residue occurs.

FIGS. 1A, 1B, 1C and 1D show various sectional shapes of the gasket member 4a, and 5 is a hollow portion. All the gasket members 4a are bent with the one surface 2 which does not cover the waterproof film 3 being the inside, and the end faces are joined to form the gasket 4 of various sizes.

When joining the end faces, only the main bodies 1 and 1 are vulcanized and completely connected as shown in FIG. 2, and the waterproof membrane 3 is butted. The gasket 4 thus formed is a concrete pipe 6
Since the waterproof film 3 is peeled off from the abutting surface and the like immediately before the insertion and connection, the product is pre-fitted to the end portion of the product and is adhered between the one surface 2 and the tube surface with the adhesive 7 before shipment. is there.

<Effect of the Invention> Since the present invention is extrusion-molded using the two-layer extruder as described above, the main body made of water-expanded rubber and the outer surface except one side of the main body are covered with a peelable waterproof film. There is an effect that the gasket member can be efficiently manufactured without requiring manpower.

Since the gasket with the above configuration was fitted to the concrete pipe in advance by using an adhesive, even in the propulsion method where the mechanical force is used to press-fit, the gasket's displacement movement and curling are eliminated, and the press-fit is securely pressed to the specified position. There is an effect of sealing with water. In the case of outdoor storage or transportation, even if the gasket is exposed to water due to rain or the like, the outer surface is covered with the waterproof film, so there is an effect that the inability to press fit due to water expansion is eliminated.

The waterproof film has an effect that it can be easily and easily peeled off from the abutting surfaces between the end surfaces.

[Brief description of drawings]

1A, 1B and 1C are side sectional views showing an example of the molded shape of the gasket member of the present invention, FIG. 2 is a front sectional view showing the joining state between the end faces of the gasket member, and FIG. FIG. 4 is a partial side sectional view showing a state in which the waterproof film is peeled off just before fitting and adhering and inserting a concrete pipe, and FIG. 2 is an uncoated main surface, 3 is a waterproof film, 4a is a gasket member, 4 is a gasket, 5 is a hollow part, 6 is a concrete pipe, 7 is an adhesive, and 8 is a connecting steel collar.

Claims (1)

[Scope of utility model registration request] 1. A gasket comprising a water-expandable rubber main body and an outer surface excluding one surface of the main body covered with a peelable waterproof film is extruded and molded by using a two-layer extruder, and the gasket is formed. The member is bent inward on one surface to make a ring by vulcanization connection between the end faces of the main body, and fitted into the outer surface of the end of the concrete pipe with an adhesive to make it waterproof immediately before connection. A joint structure for a concrete pipe, characterized in that the membrane is peeled off.