METHOD AND APPARATUS FOR CASTING METAL ARTICLES

摘要

The invention consists of method and apparatus for casting metal articles in a mould set comprising an immovable mould half (7), a movable mould half (20) and pressing punches set (18 and 25) driven by separate hydraulic cylinders. The mould in which the atmosphere is first replaced with an inert gas, is filled with molten metal pneumatically from furnace (1) by means of a gate running system (9) which is situated on one side of the mould cavity and is connected to it by means of the runner (10). Permanently controlled inert gas pressure is maintained in the furnace. In the gate running system is located a filter (11) in the region of the separation of both mould halves. The cast article shaping is performed in three stages : during the first stage the compressing is performed by the gas pressure ; during the second, after interruption of the runner by some of the pressing punches, the compressing of the thin-section parts of the cast article is performed; during the third stage the thick-section parts of the cast article are compressed by the second pressing punches. There are several ways to control the partial compressing pressure for particular regions of the cast article to ensure the same structure in the entire cast article.