Our Division
LOST FOAM FOUNDRY
Technology
First a foam pattern is moulded using Expandable Polystyrene (EPS) or co-polymer which is an exact replica of the desired casting. Runners and risers are attached by glue to the foam pattern and a cluster is made of one or more number of foam patterns. The cluster is then coated with a permeable refractory slurry coating in a homogeneous bath by dipping.
The dry coated cluster is invested in a flask by sand, then vibrated to compact the sand around the cluster in the flask. Molten metal is poured through the pouring cup into the foam cluster. The molten metal replaces the foam which gets evaporated. On solidification of the metal, the sand is drained off the flask and the tree is removed. The castings are knocked out from the metal cluster, fettled and finished before they are shipped out.
Why Lost Form
- Closer tolerances on dimensions
- Permits lesser machining allowance and subsequent reduction in the weight of castings
- No mismatch. Suitable for direct CNC/ SPM operations by eliminating pre-machining
- Merger of many simple casting components into a complex and intricate shaped single casting to save machining cost and reduction in casting weight.
- It is a Core less process hence total elimination of Fins and Flashes on the casting.
- Better surface finish. No sand inclusions and hence increased cutting tool life.
- Excellent process for intricate and complex shaped and high volume casting requirement
SUBMERGED ARC FURNACE
The main aim of this project is to produce cast iron in lumpy form / balls using reclaimed steel prills from induction furnace slag , Mill Scale which is a waste By-Product of Rolling Mills ,Cast Iron particles trapped in the Blast furnace skull, PCM fines , Sponge Iron fines (duly briquetted)
The above mentioned charge mix along with Dolomite & Coal or Coke is remelted. This is achieved by a conventional Submerged Arc Electric Furnace. The three carbon electrodes, partially submerged in the charge, are supported on hydraulic cylinders for upward and downward movements to maintain the desired electrical conditions in the furnace.
The body of the furnace is cylindrical in shape, and is lined with firebricks, silicon carbide bricks and carbon tamping paste. Three tap-holes are provided for draining out both the molten alloy and the slag. During the repair works of one of the tap holes the other functions as standby.
The raw materials are thoroughly mixed in the proper proportion before being charged into the furnace. Manual poking rods or stroker car are used for stoking the charge on the furnace top. As the charge enters the smelting zone, the alloy formed by chemical reactions of the oxides and the reluctant, being heavy gradually settles at the bottom. The slag produced by the unreduced metal oxides and the flux, being relatively lighter, floats on the alloys surface.
At regular intervals the furnace is tapped. The tap hole is opened by Oxygen lancing pipe and after tapping is completed, it is closed by clay plug.
This is basically a secondary metallurgical process where the main concept is to reclaim Iron & Steel available in waste by-product of Sponge Iron, Rolling Mills, Blast furnace and Machine shops. The Liquid metal available in the furnace is either casted in the form of lumps or poured in the pig caster machine to take the shape of pig moulds.