Centrifugal Casting for quality control of materials
1, metal material
Centrifugal Casting Enterprise Metal Materials are mainly derived from purchased materials, scrap castings of the enterprise, riser. The outsourcing of metal materials is often in bulk, very few pressed into a cylindrical, different materials are easy to confuse together, such as 316 material mixed with 304 or 430 material. Therefore, Centrifugal Casting enterprises to choose as much as possible to purchase pressed into a cylindrical material. The chemical composition of each batch of purchased material was analyzed using a spectral analyzer. If possible, the supplier should conduct field trips to evaluate whether the material is to be identified, protected and isolated.
For the enterprise scrap (waste castings, pouring risers) to be in addition to corrosion, to oil, sand and clean and dry treatment, control S, P ingredients. And, the scrap of different materials to be identified, protected, separated storage, can not be confused.
2, mold material
The performance indicators of the mold material are: melting temperature and solidification temperature range, heat resistance, thermal expansion and shrinkage, strength, hardness, viscosity, fluidity, sanding and ash. It is difficult for Centrifugal Casting enterprises to test these performance indicators one by one. Therefore, in the choice of suppliers, as far as possible to choose some of the quality management system more perfect formal enterprises, strict evaluation and confirmation of the supplier. However, as one of the most important performance indicators of mold material - shrinkage, you can test, the shrinkage of a direct impact on the casting of the dimensional accuracy and quality of the shell. At present, the domestic round cake sample line shrinkage measurement method does not consider the wax mold structure on the impact of shrinkage, it is best to refer to foreign ladder-like sample method is closer to the actual situation.
3, silica sol
Silica gel physical and chemical parameters are: SiO2 content, density, Na2O content, PH value, kinematic viscosity, colloidal particle diameter, these physical and chemical parameters mainly affect the shell strength, paint stability and paint powder ratio. As the general Centrifugal Casting enterprises are difficult to detect these physical and chemical parameters, so on the one hand to strengthen the supplier's choice, evaluation and confirmation, on the other hand, the surface layer and back layer should choose to use different specifications of silica sol, Layer selection S-830 silica sol, back layer selection S-1430 silica sol.
Centrifugal Casting Enterprises generally choose zircon powder as a topcoat. When the zirconium powder contains oxide impurities, the decomposition temperature will drop, precipitation of amorphous SiO2, and some elements of the metal chemical reaction, the casting surface "pitting" and other defects, deterioration of the surface quality of castings. Moreover, the particle size and distribution of the zircon powder have a direct effect on the powder ratio of the coating. Therefore, the choice of suppliers should be strictly controlled.
In view of the problems existing in Centrifugal Casting enterprises in our country, we should focus on solving the practical problems of production, which should be the main direction of Centrifugal Casting technology research. Specific direction is as follows: to improve the product's pass rate and process yield, reduce energy consumption and raw material consumption, training high-end talent, to achieve green Centrifugal Casting. Second, the development of key parts of the Centrifugal Casting technology, to achieve localization. Third, through the cooperation with foreign research institutions and enterprises, the introduction of digestion high Cent Centugaling Casting technology, with the factory to develop key parts of the Centrifugal Casting technology research, and into new products into the market. Fourth, strengthen the Centrifugal Casting enterprise leadership and management training, to master the modern management knowledge, establish a modern management system, so that enterprises rely on management efficiency. Fifth, to take business commissioned by the factory and the joint school to train people, and to pay special attention to its computer software training. Sixth, through the establishment of a national and regional technical training base, improve the level of Centrifugal Casting of technical staff and workers.