Application of Lost-foam casting Technology in Grate of Hot blast stove and Solution of Defects

Abstract

Lost-foam casting Technology has been applied in Manufacturing the grate of hot blast stove. According to the requirements of structure and tolerance dimension, the lost-foam unit of grate is prepared with expandable polystyrene resin beads. RTCr2 is used as the material of grate, which is poured at 1360-1380°C by Top post system. And the negative pressure range is 0.04-0.05MPa. The results show that the surface of the casting is relatively complete, and the internal structure of the casting is dense. Through inspection, the quality performance, structure dimension and manufacturing precision of casting products can meet the requirements well. But there are also some disadvantages, such as inner hole sticking sand, surface sand hole, shrinkage cavity, air hole, sand inclusion, slag inclusion, mechanical processing edge breaking. Then some corresponding effective repair methods are used to solve the defects, which guarantee the quality of the products. Some lost-foam casting data and control measures have been accumulated, which are beneficial to continuously improve the lost-foam casting process and master the key casting technologies such as lost-foam casting and hot metal casting.