Registered as a partnership firm in 1971, Simplex Castings was formally created and deployed as a legal entity on 30 Jan.'80 and went public in 1993. It was promoted by H B Shah and Arvind K Shah.The company manufactures heavy castings in grey cast iron, alloy cast iron, stainless steel and steel.

The products of the company go mainly to steel plants, power plants, mining and cement plants, Defence and the Railways. Main products go to blast furnaces and coke oven batteries. The company has technical collaborations with a number of companies for its products. Some of the firms are Nippon Steel Corporation, Japan; Ikio Iron Works, Japan; Dango & Dienenthal, Germany; China Metallurgical, China; Schalker, Germany; etc.

In 1993 a public issue was made to finance the modernisation of Urla unit.

During 1999-2000, the company successfully engineered bi-metallic rolls being used in Thermal Power Plant.

The company has for the first time in India successfully engineered Truck Frame for Deisel Locomotive Works as per drawing and design of G.M. Motors USA and with technical expertise from one of the leaders in Rail and Road Castings M/s Atchison Casting Corp. USA. The company is engaged in developing different casting for Steel Plants and also Valve and Cone Castings for supplying the same to Valve and Pump manufacturers.