The Bureau of Indian Standards (BIS) has awarded the first license to produce Structural Weather Resistant Steel (Corten Steel) to Tata Steel’s Jamshedpur plant.
The Grade WR FE 490 H steel, conforming to IS 11587, will be used to manufacture shipping containers and other heavy-duty weather-proof applications including rail wagon side panels, rice mill containers, building construction, street furniture and upmarket works of art, signs, chimineas and fire bowls.
The license provided to Tata Steel to produce Corten steel is part of India’s larger endeavour to reduce country’s dependence on import of shipping containers, manufactured using Corten Steel.
Corten steel is a group of steel alloys which were developed to eliminate the need for painting and form a stable superficial rust layer after long atmospheric exposure. It is used specifically in extreme weather conditions due to its high level of weather and corrosion resistance.
The name comes from the original brand name COR-TEN which was registered in 1933 by US Steel Corporation. ‘COR’ comes from CORrosion resistance, while ‘TEN’ comes from TENsile strength – two of the properties of weathering steels.
Weathering steel Corten has overcome rust, which is the weakest point of steel, in a unique manner, by actually using rust.
When Corten, with bare specifications, is left in the atmosphere, rust occurs first in the same way as ordinary steel, but dense protective rust forms on the surface of the steel due to the action of the alloy element over time, inhibiting the later development of further rust.
Since Corten has excellent weather resistance, it can be used without any coating. It provides not only the economic effect of a reduction of recoating cost, but an aesthetic effect with sedate color of protective rust.
Essentially attributed to the rising demand from the construction industry, the global weathering steel market size is estimated to be around $990 million (2018) and is expected to expand at a CAGR of 5.6 per cent till 2025.
Building India’s capability to produce Corten Steel will open fresh opportunities for domestic cargo transportation leveraging the vast expanse of inland waterways of India.
This will enable movement of bulk cargos like cement, food grains, fertilisers etc. through coastal and inland waterways in containerised form — an economical, ecological, and easier mode of transportation — and will reduce the cost of logistics and handling charges.
Huge Domestic Shortage
Presently, only a few small domestic firms manufacture containers, with a major chunk being imported from China, which has a monopoly in the sector.
An inter-ministerial committee formed to chalk out a plan to create capacity for manufacturing shipping grade containers in India, had looked into issues like availability of specified quality of steel needed for manufacturing containers.
The committee during its interaction with stakeholders was appraised about the lack of Indian standards for steel used in making containers. The committee took up the matter with the BIS, which has now issued an Indian standard, which is equivalent to Corten-A steel specification.
The Steel Ministry has now asked the steel manufacturers to get themselves registered with BIS and obtain a license to roll steel according to the standards specified.