The Application of Lost Foam Casting method

Abstract

- The gearbox housing is a large piece with a complex shape that is prone to defects such as incomplete filling, shrinkage, air holes and other defects in the Lost Foam Casting (LFC) process, as well as the shrinkage of EPS in mold manufacturing. To reduce production time and costs, increase casting efficiency, and reduce environmental pollution by reducing the number of test castings to find the optimal filling system for the part of the gearbox housing, the numerical analysis needs to be applied[i].

- This paper applies numerical method FEM to predict the filling process and casting defects such as shrinkage, pitting and other defects from different filling system locations, there by selecting the optimal filling system[ii] for the detailed molding of the gearbox. In order to obtain the best results in a reasonable timeframe, the industrial casting software Procast, one of the best casting application now, was used. The article focuses on four ways to set up the pouring system: vertical pouring from the outer bottom (Figure a), vertical pouring from the top (Figure b), vertical pouring from the inner bottom (Figure c), and horizontal pouring from the inner bottom (d).

Fig 1. Pouring system

[i] .Richard W. Heine, Carl R. Looper, Philip C. Rosenthal, Principles of Metal Casting (Mc Graw -  Hill Book Company, New York, 1976).

[ii] .Phan Tử Phùng, Nguyễn Ngọc Thư, Nguyễn Dụ, Sách tra cứu đúc gang – tập II,( Nhà xuất bản khoa học kỹ thuật, Hà Nội, 1985).