Over the years, COTS production due to the diversity of the products is not fixed, size, make the mechanization, automation technology equipment becomes difficult, so far, most are still mainly based on manual intermittent unit type production line. Recently, some of the larger professional manufacturers have begun to realize the continuous production expected molding and curing process from the gum, so that the production efficiency is greatly improved, greatly improving the working environment and the intensity of labor.
In recent years, injection, extrusion and winding technology development, rubber molding vulcanization equipment makes the COTS production gradually embarked on mechanization and automation. Effect of roller on the overall performance of the system is very large, the process operation and the quality of the production is very strict, many of its products have been listed as the fine product category, the control of rubber, plastic material selection and the dimensional precision of products is the key. The surface of rubber rollers are not allowed to have any impurities, trachoma and bubbles, but can not have scar, defects, grooves, cracks and local sponge and different soft and hard phenomenon. Therefore, the requirements of rollers in production process, must be absolutely clean and Seiko secret agents, to realize the operation standardization, standardization. Combined with the rubber, plastic and metal core paste and injection molding, vulcanizing and grinding processes are therefore become the process of high technology content.
A compound, preparation The roller, the mixing of rubber is the most key link. Cots rubber species from the natural rubber, synthetic rubber and special material more than 10, rubber content is 25% ~ 85%, the hardness of soil (0 ~ 90), across the range of maximum. Therefore, how to make these mixing uniform has become a big problem. The conventional method is to use open smelting machine with a variety of masterbatch form of mixing process. In recent years, more enterprises to use mesh type mixer, mixing with piecewise prepared compound.
Rubber after achieving uniform mixing also used rubber filter for filtering glue, glue in eliminating impurities. Then the rolling machine, extrusion machine, laminating machine made no air bubbles and impurities in the film or tape, for the roll forming. In forming before, was also the appearance inspection strictly on the film, adhesive tape, defining Park, keep fresh surface and prevent adhesion and deformation. Because the roller mostly non molded products, once the rubber surface impurities and bubbles, grinding on surface in post cure is possible blisters, which will lead to the emergence of exceed the standard roller repair, even scrapped.
Two, forming Roll forming is mainly adhesive coated with rubber on metal core, a packing method, extrusion, molding, injection molding and injection method. At present, mainly by mechanical or manual paste molding, the majority of foreign has realized automation. Large and medium sized cots basically adopts profiling extrusion, extrusion film with continuous paste molding or extruding bar continuous winding mode of production. At the same time, in the molding process with microcomputer automatic control the size and shape, and some also used extruder angle and special-shaped extrusion molding method.
The molding method can not only reduce the labor intensity, but also can eliminate the possible bubble. In order to prevent the roller vulcanization and prevent bubbles and deformation of sponge production, especially for the packing process of cots, external to adopt the method of flexible pressurized. Usually tied winding layers of cotton or nylon cloth in cots appearance of bread, then wire or fiber rope to be fixed pressure. Although this process has already realized mechanization, but due to the removal of sulfide dressing, forming a "appendix" process, so that the manufacturing process is complicated, but due to the use of package Jabu, winding rope times are extremely limited, consumption and waste.
For small and micro cots can use manual patch, extrusion, injection pressure, injection into and casting and other production processes form. In order to improve production efficiency, most of the already molding method, and the precision is much higher than the non molding method. Solid rubber injection pressure, injection and liquid rubber casting, has become the main mode of production.
Three, sulfide At present, the curing method of large and medium-sized rollers is still the autoclave curing, although flexible pressurizing patterns have changed, but not yet out of transportation hoisting and unloading heavy burden. Vulcanization heat steam, hot air and hot water 3 heating methods, is still the mainstream of steam. Because of the metal core contact with water vapor, and the special requirements of the roller, the indirect steam curing, time will be extended to 1~2 times, commonly used in hollow core rollers. To not use autoclave curing special rubber roller, sometimes take hot cure, but treatment of water pollution to be solved.
In order to prevent the rubber and metal core have different shrinkage due to thermal differences caused by the delamination between rollers and rubber core, the general use of slow heating vulcanization boost mode, the curing time is required than rubber vulcanization time much longer. The large roller to achieve internal and external uniform curing and thermal conductivity of the metal core and a rubber are similar, stay in the pot time often up to 24~48h, is about 30~50 times of normal rubber vulcanization time.
Small and micro rubber roller have been largely changed to molding vulcanizing machine vulcanized, completely changed the traditional curing rollers. In recent years, but also the implementation of injection machine and mold, vacuum curing, and can automatically open and close mode, the degree of mechanization and automation is improved greatly, and the short curing time, high production efficiency, good product quality. Especially the use of rubber injection molding machine, the molding and curing two.
