Zinc coated steel sheets in India -
An imperative for cooperative market development efforts

by

L Pugazhenthy, Executive Director,
India Lead Zinc Development Association

One of the earliest steel products to be hot dip galvanized is the Zinc coated steel sheet, traditionally known as the galvanized sheet. Originally they used to be coated in cut sheet installations with fairly heavy Zinc coating weights due to the absence of an effective wiping system. Gradually, due to technological developments and volume production, the continuous galvanizing technology picked up momentum and today they are widely adopted the world over. At the same time, several new types of Zinc as well as Zinc alloy coated steel sheets have been developed because of the increasing customer needs and expectations.

India has got a large capacity for some of these Zinc coated steel sheets (except Galvalume & Galfan). The time has come now for the entire steel sheet coating industry in the country to come together on a common platform and launch aggressive market promotional and customer awareness programmes.

Zinc Coated Steel Sheets

The traditional galvanized sheet consists of plain and corrugated (generally known as galvanized plain (GP) and galvanized corrugated (GC) sheets. Zinc - aluminium alloy coated steel sheets were subsequently developed to cater to specific market needs; one of them (55 per cent Aluminium Zinc alloy) is known as Galvalume or Zincalume steel sheet. Galfan (95 per cent Zinc - 5 per cent aluminium with a 'misch metal' addition) is another variety under this category. Galvanized steel sheets are also given a paint coating (organic), which are known as color coated or pre-painted steel sheets. Steel sheets, after the conventional galvanizing operation, are sometimes made to pass through an inline diffusion process in order to produce Zinc iron alloy coated substrate and these are called "galvannealed" sheets.

Applications

Each one of the above coated sheet products has well-defined market segments. The galvanized plain steel sheets are used for making boxes, containers, mugs, desert coolers, airconditioning ductings, fabricated products etc. The galvanized corrugated steel sheets are used in the construction sector for roofings, partitions, sidewalls etc., Galfan coated sheets offer an improvement over the galvanized steel. In addition to better corrosion resistance, they also provide enhanced formability and paintability characteristics.

There are about 90 Galfan licencees and the world annual production currently exceeds 1.0 million tonne, the market distribution being 73 per cent architectural, 17 per cent appliance, 6 per cent automobile and 4 per cent others. Galvalume sheets are used mainly for building panels, where excellent atmospheric corrosion resistance is required. These sheets give a good barrier protection (from aluminium) and an equally good sacrificial protection (from Zinc). These sheets are used for roofing and cladding both bare or painted. Galvannealed steel sheet is an ideal material for use in the automotive sector (for outer and inner panels), white goods etc.

Domestic & Export Markets

While India has established itself as a major exporter of flat products including Zinc coated steel sheets, the domestic market scenario is bleak. There are quantum jump growths in our automobile production, appliances demand, construction etc., and the penetration of Zinc coated products is indeed very poor. This is largely due to the lack of awareness on the part of the users, designers, specifiers etc. Therefore the need of the hour is that the coating industry should come together and launch cooperative promotional campaigns, so that the cake is enlarged.

A strong domestic market base is in their long term interest, as any external market support or incentive may not be there for all times to come.