What is large steel casting?
Large steel castings usually need to pour dozens or even hundreds of tons of molten steel, and some sand cores are surrounded by a large amount of molten iron. The hot action time of molten steel on molding materials is very long, the static head is also very high, and the working conditions are extremely harsh. Therefore, chromite sand is widely used as surface sand in the production of large steel castings. At present, the chromite ore with good quality is high-quality foundry grade chromite ore imported from South Africa. Using chromite sand as the core material, although the expansion rate is low, the large angle coefficient of chromite sand, poor particle shape ratio and poor core fluidity will lead to poor permeability and collapsibility in the later stage. In some cases (such as some thin skin or blind hole sand cores), even chromite sand is difficult to clean out, which increases the cleaning work of castings accordingly.
Present situation of large steel casting
In order to solve the problems of thick surface, hot spot and sintering, veining and sand sticking at the riser root of large steel castings, the basic experiment and production practice of alkali phenolic resin/ sodium silicate fused ceramic sand were carried out. The results show that the use of alkali phenolic resin / sodium silicate ceramic sand on the thick surface, hot spot and riser root of large steel castings can effectively prevent metal penetration and sand adhesion, and reduce the pollution of dust in the process of casting sand production.
Why can Fused ceramic sand influence large steel casting?
The production of large steel castings in China has been using sodium silicate sand CO2 process since the 1970s. With the increasing requirements of users for product quality, this casting process has been difficult to meet the requirements for casting quality. In most cases, subsequent grinding and other means are required to meet the quality requirements of castings, which will not only increase the manufacturing cost of castings. It will also extend the production cycle of castings. The use of Fused ceramic sand in the parts of large steel castings that are easy to stick to sand, such as the included angle, groove, and the hot junction of slender holes, can eliminate the local sand sticking or iron coated sand phenomenon, reduce the cleaning cost of castings, and improve the surface quality of castings.
Fused ceramic sand factory
Sanmenxia Qiangxin Foundry Material Co., Ltd. specializes in the production of fused ceramic sand, which is resistant to high temperature, easy to collapse, small thermal expansion, good regeneration performance, smooth surface, high casting precision, and non- sticking sand. It has good casting performance and is recognized by casting experts at home and abroad.