Magnesium Casting Production
Chevrolet Foundry Processes for Pratt & Whitney Engine Components

Fig. 1. Pouring magnesium castings on a moving conveyor line in a Chevrolet foundry.

To supply requirements for Pratt & Whitney aircraft engine contracts, the Chevrolet Motor Division of General Motors Corporation converted a large part of its grey-iron foundry in Michigan to magnesium production. This Chevrolet unit, which in pre-war days merited the title "world's largest grey-iron foundry", now processes two metals as the grey-iron operation continues side by side with the foundry's considerable magnesium output. Castings now being produced by Chevrolet for aircraft engines include the oil drain sump, crankcase blower section, supercharger insert, two intermediate crankcases, two rear crankcases, and the diffuser-impeller cover.

Although Chevrolet foundry men had to acquire a background of knowledge on magnesium, their experience in foundry methods such as pouring procedures and core making made it possible to develop several new approaches which were reflected in increased output and time saving. An innovation in the industry is the practice of pouring magnesium on a moving conveyor. Another process new to general magnesium procedure is the pouring of the metal through sand filters instead of metal strainers.