Precision Casting process common problems
Precision casting is widely used in metal processing technology, in China's modern industry plays a huge role, with the precision casting in China's extensive use, it brought the drawbacks also exposed.
First, the oxidation of slag
The reason for the occurrence of oxidized slag is generally because the charge is not clean, or in the course of the use of the furnace too much use, there is a reason can also lead to precision casting process oxidation slag, that is, precision casting system Of the poor design, in the filling when the improperly set.
Second, stomata, shrinkage
Stomatal problems in the process of precision casting the most common, it is generally due to the poor mold caused by the mold, the mold coating system spray bad, improper cooling ring set, can also lead to the formation of pores, shrinkage.
Precise casting process, the occurrence of cracks is very common, the design of the mold is unreasonable, sharp corners, thick wall thickness difference will lead to the occurrence of cracks, in order to eradicate the crack phenomenon, improve the mold structure design is inevitable The choice, only the mold design is reasonable, the solution to the problem can help.
Precision casting technology in China's processing technology is very common, with the development of technology, which drawbacks are increasingly apparent, we only analyze the root causes of problems in order to better solve the problem.
Precision casting molding generally do not exert pressure on the equipment and mold strength requirements are not high, the product size limit is small, the product is also low internal stress. Therefore, the production of less investment, can be made excellent performance of large parts, but the production cycle is longer, after forming to be mechanical processing. In the traditional precision casting on the basis of derived perfusion, embedded casting, pressure precision casting, rotary precision casting and centrifugal precision casting and other methods.
① perfusion. This method and the precision casting of the difference is: precision casting finished products that come out from the mold; and filling the mold is part of the product itself.
② embedded casting. Place a variety of non-plastic parts in the mold cavity and cure with the injected liquid material to enclose it.
③ pressure precision casting. In the precision casting of the material to exert a certain pressure, is conducive to the viscous material into the mold, and shorten the filling time, mainly for the epoxy resin precision casting.
④ rotary precision casting. The material into the mold, the mold at a lower speed around the uniaxial or multi-axis rotation, the material by gravity distribution in the cavity wall, by heating, curing and stereotypes. Used to manufacture spherical, tubular and other hollow products.
⑤ centrifugal precision casting. The amount of liquid material will be injected around the uniaxial high-speed rotation, and can be heated in the mold, the use of centrifugal force to distribute the material to the cavity on the wall, the physical or chemical role of curing into tubular or hollow cylindrical products (see [ Precision casting]). Monolithic precision casting nylon parts can also be formed by centrifugal precision casting.