JPH0335090B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a fire-resistant pipe joint, and particularly to a method for manufacturing a fire-resistant pipe joint for water supply and drainage pipes in buildings, characterized in that the outer periphery of the inner pipe of the joint made of synthetic resin is surrounded by a fire-resistant material. Regarding the manufacturing method of a fire-resistant pipe fitting, its specific structure is made of an inorganic condensed material that is formed from a plurality of split shapes, the inner diameter of which is slightly larger than the outer diameter of the inner pipe made of a synthetic resin pipe fitting with a socket. An outer tube structure made of a pipe joint member with a socket is molded, and a plurality of split portions of the outer tube structure are fitted from the outside along the outer circumferential surface of the inner tube to form a joint portion. The present invention relates to a method for producing a fire-resistant pipe joint, which is characterized in that a synthetic resin inner pipe and an outer pipe made of an inorganic condensed material are joined together and a cavity is provided in the pipes.

A compressible layer made of cotton, synthetic fiber, asbestos, or foamed material is attached to the outer periphery of a conventional synthetic resin pipe, and mortar is coated on top of it to prevent cracks that occur when the mortar dries. There is.

This method can prevent cracks in the mortar that occur when the mortar dries, but in order to attach the layered body, it is necessary to attach the layered body to the synthetic resin pipe in advance, which requires extra steps and materials, and is not economical. This results in poor productivity and significantly hinders productivity.

In addition, if an asbestos cement layer is directly coated on the outer surface of a synthetic resin pipe fitting at room temperature,
If hot water passes through the inner surface of the pipe joint or if it is exposed to direct sunlight in the summer, cracks will occur in the outer pipe and the fire resistance will be impaired.

The product of the present invention eliminates the above-mentioned drawbacks, and will now be described based on the drawings of the present invention.

FIG. 1 is a longitudinal sectional view of a refractory pipe joint manufactured by the method of the present invention, and FIG. 2 is an end view thereof.

In FIGS. 1 and 2, 1 is an inner tube of a synthetic resin pipe joint with a socket, and 2 is an outer tube with a socket formed from a mixture or slurry of asbestos and cement.

In addition, as the molding material for the outer tube, inorganic fibers such as glass fiber and rock wool may be used instead of asbestos.
Further, asbestos and glass fiber may be used together. Reference numeral 3 denotes a space provided between the inner pipe 1 with a socket and the outer pipe 2 with a socket, and the space is provided approximately concentrically on the end face of the fire-resistant pipe joint. (See Figure 2) 4 is the shoulder of the large diameter opening formed at each opening of the synthetic resin pipe fitting inner pipe, and a void is formed between the inner pipe with a socket and the outer pipe with a socket. The inner tube is supported by the shoulder portion to prevent the inner tube from falling out.

FIG. 3 is an external view showing an embodiment of a fire-resistant pipe joint manufactured by the method of the present invention.

FIG. 4 is a diagram showing a joint portion of a fire-resistant pipe joint manufactured by the method of the present invention.

Here, a method for manufacturing a fire-resistant pipe joint of the present invention will be explained. As shown in Figure 4, a mixture of asbestos and cement is molded into a shape that looks like a pipe fitting with a socket cut vertically from the center using a mold, and is then molded into two halves. This is manufactured by attaching the joint from the outside along the outer circumferential surface of a synthetic resin pipe joint with a socket, and joining the joint portion 5 with an adhesive or the like. The end surface of the joint portion of this outer tube with socket may be flat or may be assembled in the shape of a gear.

Incidentally, depending on the shape of the pipe joint with socket, it may be molded in three or more parts. When using these pipe fittings with split sockets, it is also possible to tighten them by wrapping an iron band around the outer periphery.

When forming the two-piece shape, the inner diameter of the outer tube with socket is made 1 to 2 mm larger than the outer diameter of the inner tube with socket, and in the case of a large diameter, it is about 5 to 8 mm larger, so that the outer tube with socket and the outer tube with socket are combined. A hole is provided between the resin inner tube and the tube.

Since the present invention has the above-described configuration, even if hot water is passed through the piped fire-resistant pipe joint, no cracks or cracks will occur in the outer pipe of the fire-resistant pipe joint. Since the present invention uses a synthetic resin pipe with a socket for the inner pipe, the inner pipe with a socket will not be clogged with water scale or become clogged, and it will also prevent fires, which is a drawback of synthetic resin inner pipes with sockets. The fire resistance of the outer pipe with a socket protects against weak points, making it ideal for water supply and drainage pipes in buildings.

Since the present invention does not require any member between the inner tube with a socket and the outer tube with a socket, the manufacturing process is simplified and the cost of the product is reduced. The pipe fitting produced by the method for manufacturing a fire-resistant pipe fitting of the present invention is a pipe fitting with a socket provided with a large-diameter opening,
Since the outer surface of the shoulder part connected to each large diameter part of the synthetic resin pipe fitting inner pipe is in contact with the inner expanded part of the outer pipe, a void is formed between the inner pipe and the outer pipe. The inner tube will not fall out even if

The pipe joint manufactured by the method for manufacturing a fire-resistant pipe joint of the present invention has a large diameter socket at the end opening of the pipe joint. Since the socket part at the end is a large diameter part, it is impossible to fit the small diameter part of the outer pipe along the axial direction of the inner pipe to make an inner and outer double pipe. Although there was a problem in that the pipes could not be directly connected coaxially, the method for manufacturing a fire-resistant pipe joint of the present invention utilizes a plurality of split shapes as constituent members of the outer pipe, thereby connecting the outer pipe to the inner pipe. They were able to easily locate it on the outer periphery of the wall, and succeeded in creating an empty space.

When arranging the split-shaped part that becomes the outer pipe component on the outer periphery of the synthetic resin inner tube, the shoulder provided on the split-shaped part is attached to the shoulder provided at the enlarged diameter portion at the end of the inner tube. By fitting, the axial positioning of the pipe joint is ensured, and the large-diameter end portion of the inner tube and the large-diameter end portion of the split shape that becomes the outer tube maintain a desired distance from each other. Once they are concentric, the space between the inner tube and outer tube can be directly measured or confirmed by interposing adhesive on the side edges of the adjacent split shapes. In other words, by simply observing the state of concentric circles at the enlarged opening end of the pipe joint, or by creating a concentric state by some other means, it is possible to maintain thermal insulation and eliminate the effects of expansion of the inner pipe. Empty the inner and outer tubes to prevent it from affecting the tubes
This has the effect of making it possible to secure parts without having to carry out any particularly complicated processing in the manufacturing process.

This makes it possible to improve productivity in the manufacturing method of fire-resistant pipe joints, greatly increase the dimensional accuracy when forming the void, and greatly reduce the number of quality control steps in the manufacturing process. This has the effect of making it possible to

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a fire-resistant pipe joint of the present invention, FIG. 2 is an end view thereof, and FIG. 3 is a diagram showing an embodiment of the fire-resistant pipe joint of the present invention. FIG. 4 is a diagram showing the joint portion. 1...Synthetic resin pipe joint inner pipe, 2...Asbestos cement outer pipe, 3...Air space provided between the outer pipe and inner pipe, 4...Shoulder of large diameter opening, 5... joint part.

Claims (1)

[Claims] 1 A synthetic resin pipe fitting with a socket in which three or more end openings have a slightly larger diameter than the middle part is used as an inner pipe, and then multiple split shapes are used to wrap the outer periphery of the inner pipe. An outer tube component made of a pipe fitting member with a socket made of an inorganic condensed material is formed to have a slightly larger diameter than the inner tube, and then a plurality of split shapes for the outer tube component are formed around the outer circumference of the inner tube. are attached to the inner tube from the outside and positioned concentrically, and a plurality of split-shaped, large-diameter socket portions as constituent members of the outer tube are attached to an outer shoulder portion of the socket portion of the inner tube. Insert the inner shoulder part of the part that becomes
A fire-resistant pipe joint in which the joined parts of the split shapes adjacent to each other are joined together with an adhesive or the like to form an outer pipe, and a space is provided between the outer pipe with a socket and the inner pipe with a socket. Production method.