JPS6340645B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a coated tube body with high roundness and excellent adhesion of the coating layer.

Recently, water supply and drainage pipes have been proposed in which the outer circumferential surface of a synthetic resin pipe such as a hard vinyl chloride pipe is coated with a fire-resistant inorganic material, or the outer circumferential surface of a metal pipe is coated with a similar coating to provide dew-proofing and soundproofing properties. The former is easy to process and install, such as cutting and gluing, and it not only has performance such as preventing condensation, but also protects the upper floors and other areas in the event of a fire when the building is used by penetrating each room. In the latter case, conventional cast iron pipes and It is increasingly being used to replace bare water supply and drainage pipes made of hard vinyl chloride pipes.

One of the methods for manufacturing these coated tubes is to apply a mixture of water and hydraulic inorganic materials to a certain thickness on a fabric made of organic fibers or mineral fibers, such as cloth or pine, to form various types of tubes. A method of wrapping it around the outside of the body has been proposed (for example, Japanese Patent Application No. 54-19705).
issue). When using this method, increasing the number of wraps will improve the reinforcing effect of the covering layer, but there are problems in terms of cost, problems with reducing fire resistance in the case of fabrics using organic fibers, and the need to use coarse aggregate. Due to drawbacks such as the fact that the coating layer is not uniform, the coating thickness must be increased.

Increasing the coating thickness naturally reduces the number of turns of the cloth material, which is advantageous, but it also creates steps at the beginning and end of the winding based on the thickness of the coating layer, reducing the roundness of the coated tube. If it is cured and manufactured into a product as it is, problems will arise in connection with the joint pipe, joint treatment with joint fittings, and compatibility with support fittings. Of course, it doesn't look good either. The above-mentioned step at the beginning of the winding is subjected to pressure during the winding process on the tubular body and is considerably corrected, but the step at the end of the winding cannot be easily erased, but the easiest finishing method to eliminate it is This method involves uniformly pressing the uncured cladding from the outside with a rotating roller or the like, but in reality, the uncured cladding extruded from the end of the winding is smoothed onto the surface of the cladding. Not only does it not distribute, adhere to the surface of the pressure roller, or fall onto the floor and make a mess, but it also causes a large amount of expensive covering material to be disposed of.Although the end of the winding can be improved to some extent, the overall effect is as described above. The roundness is not sufficient and there remains an economical problem.

The present invention aims to improve the problems of the above-mentioned method for producing a cladding body, and to provide a method for producing a peelable cladding tube having a high degree of circularity, which is economically advantageous, and has a cloth-like structure. be.

More specifically, the object of the present invention is to wrap a cloth-like body such as cloth or mat coated with a water-kneaded material containing a hydraulic inorganic material as a main component around the outer peripheral surface of a tubular body, with the water-kneaded material inside. In the manufacturing method of the cladding pipe body, even when the number of cladding layers to be wrapped is relatively small, such as 2 to 3 layers, the roundness is still high, causing problems with the inner diameter of the support fittings and joint fittings during piping. It is an object of the present invention to provide a method of manufacturing a cladding tube body that is not available in the prior art.

Another object of the present invention is to ensure the minimum coating thickness necessary for fire resistance by making the coating thickness uniform over the entire circumference, and to eliminate excess coating, thereby reducing and effectively utilizing the materials used and improving the efficiency of the coating tube body. An object of the present invention is to provide a method for manufacturing a cladding tube body that is lightweight.

The method of the present invention will be explained in detail below.

A water kneaded material mainly composed of a hydraulic inorganic material is applied to the surface of a long cloth-like body such as cloth or pine made of organic or mineral fibers, or is wrapped around the outer periphery of a synthetic resin pipe or a metal pipe. However, by scraping off the water-kneaded material on the end of the winding end of the fabric over a desired length and then wrapping it, the fabric can be leveled by pressing the water-kneaded material. In addition, it is economically advantageous because almost no excess water-kneaded material comes out during the conditioning operation, and the water-kneaded material that is moved by the pressure removes the wetness that has been scraped off once applied. It has the characteristic of being easy to spread because it can be spread on the surface of a good cloth-like material.
The scraping length of the applied water-kneaded material depends on the coating thickness, but in consideration of practical roundness, it is appropriate to be 1/3 to 1/30 of the outer circumferential length of the coating layer. If the length is 1/3 or more, it is difficult for the applied water kneaded material to spread over the entire scraped part, so the end of the winding tends to peel off easily. On the other hand, if it decreases to 1/30 or less, the amount of water-kneaded material protrudes from the edge of the fabric during the above-mentioned leveling process, and it may get in the way during the process to achieve roundness later on or adhere to the processing equipment. , it is undesirable to fall and become waste.

Methods for scraping off the water kneaded material include a method of passing it between two parallel nip rolls and a method of using a flat scraper, but the scraping method is not limited to the present invention.

The target of scraping is the entire water kneaded material on the surface of the winding end of the cloth material, but the boundary between the part to be scraped off and the part not to be scraped off may be stepped, or it can be gradually It may be formed into a gentle plate shape by scraping off a lot.

The cladding body that has been scraped off and rolled up as described above is rotated around its central axis while gradually pressing more strongly against other rotating pressure rollers installed in parallel, or by rotating two rollers in the same direction. By placing the uncured cladding tube on parallel rollers and rotating it, a perfectly circular cladding tube can be obtained by utilizing the pressing force due to its own weight.

The rounding treatment is carried out for a period of time until the water kneaded material on the cloth spreads near the ends of the cloth, but it is preferable not to carry out the process suddenly in order to obtain uniform spreading.

As the core tube for wrapping in the present invention, a synthetic resin tube or a metal tube can be used as is, but a core tube for forming a tubular body is prepared separately, coated with a hydraulic inorganic material, and after hardening is coated with another desired material. Of course, it is also possible to replace the core tube.

If the manufacturing method of the present invention detailed above is implemented,
The roundness of the cladding pipe body has been significantly improved, which not only eliminates troubles when combining with support fittings and joint fittings during piping, but also improves the appearance.
No peeling was observed at the ends of the cloth.

The method for manufacturing a cladding tube according to the present invention enables the manufacture of a nearly perfect circle even with a small number of turns, such as 2 to 3 layers, so the amount of cloth or mat can be kept to the minimum necessary, and the amount of hydraulic inorganic material per layer can be reduced to a minimum. Since the coating thickness of the water kneaded material containing as the main component can be increased, it has the advantage of being able to be used in combination with coarse aggregate for the purpose of increasing the volume.

The present invention will be explained in more detail with reference to Examples below.

Example: Two parallel rollers with a diameter of 100 mm and a length of 2.5 m that rotate inward from each other with a gap of 2.8 mm are made of real cotton cheesecloth with a width of 2.1 m and a hydraulic inorganic material with the following composition as the main components. The water-kneaded product was passed through the mixture and the water-kneaded product was applied uniformly onto the cheesecloth to a thickness of 2.7 mm. Approximately 72 cm of this coated cheesecloth was wrapped around the outer circumference of a rotating hard vinyl chloride pipe with an outer diameter of 114 mm around its axis, with the coated side facing inward.
The water kneaded material about 1 cm above the end of the winding was scraped off with a scraper knife on a rubber roller rotating in the same direction as the traveling direction of the cloth, and then wound.

Composition Portland cement 100 (parts by weight) Silica sand 30 Light aggregate (perlite) 15 Asbestos 5 Thickening admixture (methylcellulose)
0.15 Water 47 While rotating this uncured coated tube body around its axis in the direction in which the cloth material is wound, a freely rotatable rubber coated roller of about 200 mm in diameter is gradually brought into contact with the uncured coated tube body in parallel with it and pressed to release water. Level differences in the kneaded material were smoothed out. The pressing treatment was stopped when the water kneaded material spread to the ends of the fabric.

The coated tube body having obtained roundness was cured by steam curing at 50° C. for one day and night, and then air-dried for two weeks.

The thickness of the coating layer of this product was about 5.5 mm, with a variation of ±0.3 mm, and the roundness was extremely good.

Further, there was no tendency for the cloth-like body to peel off at the end of the winding.

Claims (1)

[Claims] 1. While or after applying a water kneaded material containing a hydraulic inorganic material as a main component to a cloth-like body, the cloth-like body is wrapped around the outer peripheral surface of the tubular body with the coated side facing inside to produce a coated tube body. A method for producing a coated tubular body, characterized in that the water kneaded material applied to the winding end side end of the cloth-like body is scraped off and wound around the outer peripheral surface of the tubular body, and then pressure is applied from the outside. 2. A method for manufacturing a cladding tube according to claim 1, wherein the water kneaded material applied to the winding end side end of the cloth-like body is scraped off over 1/30 to 1/3 of the outer circumference of the cladding tube. . 3. The coated tube body according to claim 1 or 2, wherein the tube body around which the cloth-like body coated with the water kneaded material is wound is subjected to pressure treatment in the normal direction of the tube body while rotating the tube body. Manufacturing method.