Manufacturing Process
Manufacturing Process Chart
Forgings
1. Melting and Ingot Making
Steel is melted and refined by 120 ton basic electric arc furnace. Ladle refining process follows in order to lower gas content and impurities. At ingot making, vacuum casting is applied to obtain good internal quality. Hydrogen in ingot should be reduced as low as possible by means of ladle degassing and vacuum casting.
Our maximum ingot weight is 670 ton which is the heaviest in the world. JSW has also 150 Electro Slag Re-melting (ESR) equipment to uniform chemical composition in the ingot.
2. Forging
After heating the ingot to optimum high temperature, the ingot is forged by hydraulic presses (one 3,000-ton and two 14,000-ton). Forging process has two major purposes which are to form the required shape and to refine grain size inside of steel ingot. High fatigue strength is given by this process.
3. Heat Treatment
After forging process, quality heat treatment is performed to obtain proper mechanical properties and fine structure.
JSW has low frequency induction heating furnace for Steel Mill Rolls such as high hardness cold mill rolls.
4. Machining
After heat treatment, products are machined. JSW has more than 100 machines in its machining shop.
The major facilities include: deep hole boring machine, high speed trepanning machine, lathe, vertical lathe, horizontal boring and milling machine, double housing milling machine and so on.