Raising the Bar in Construction

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The Indian rebar market is at the cusp of growth and may witness a dramatic surge in demand, thanks to the government’s thrust on infrastructure and housing.

A glimpse at the product-wise classification in the Indian steel industry shows that among long steel products, bars and rods as well as structurals make up for a lion’s share of the total. According to available figures for FY18, bars and structurals comprise almost 44 MnT of the 45.10 MnT of long steel products manufactured. That the country’s construction industry is heavily reliant on secondary manufacturers is borne out by the fact that small and mid-sized manufacturers have produced 16. 53 MnT of reinforcement bars out of the nation’s total production of 26.24 MnT in FY18 – an eyebrow-raising 62%. The rest has been produced by the integrated steel mills comprising the heavyweights SAIL, RINL, Tata Steel, JSPL and JSW.
Rebars form the backbone of any reinforced cement concrete (RCC) structure, whether it is the foundation, columns, beams or slabs, and their quality is critical in defining the overall quality of the structure. Rebars are used in RCC constructions varying from large infrastructure projects like bridges, ports, airports, urban infrastructure, industrial plants and commercial buildings to small RCC-based individual house constructions.
TMT bars are the backbone of civil construction. They are deeply anchored into concrete to bear the load of buildings, slabs, beams and columns. They should be able to withstand the furies of nature such as windstorms and earthquakes. The consumption of rebars in India is currently estimated at about 24 MnT per annum, valued at about INR 1.2 trillion.
Considering the average steel intensity of about 10% by value in an RCC construction in India, the total construction industry can be valued at 10 times the valuation of the rebar industry, which works out to an astronomical INR 12 trillion per annum. These are current figures; with infrastructure projects planned till 2025 or 2030, the figure is expected to swell in multiples. With such a large construction industry corpus being critically dependent on the quality of steel rebars used, it is imperative that all efforts are made to produce and promote the use of good quality rebars.

Indian TMT Market On Cusp Of Growth

Although both the integrated and secondary players populate the rebar market, the latter outweighs the former. Secondary manufacturers constitute around 55% of the rebars market in India. The use of rebar grades and products has undergone remarkable changes of late. Though the IS:1786 building codes specify only Fe-415 for reinforced cement concrete, its usage is declining as the market is shifting to higher grades. The construction industry has started adopting newer grades like Fe500, Fe550, and Fe500-D. Similarly, on the application side, rebar use has been moving toward higher value-added products like corrosion-resistant steel rebars, epoxy-coated, earthquake-resistant and galvanised rebars.
Rebars with major diameters between 8mm and 25mm find application in buildings, bridges and highways. With an estimated demand of around 40 million tonnes, the market is dominated by secondary producers. While these producers manufacture rebars through processing of imported steel scrap, the primary producers use iron ore as raw material.
Chhattisgarh and Maharashtra have been regarded as centres for TMT production, where many additional capacities have been set up.
The Indian market is characterised by many regional players serving local customers at par or discounted pricing compared to national players. But their acceptance among consumers is good, resulting in high business volumes. Many large and small players have strengthened their presence in the regional markets making the entry of national-level players difficult. Global consultancy Frost & Sullivan forecasts India’s demand for rebars to hit 41.82 MnT by 2020-21.

Key Material In Construction

Rebars have found application in construction particularly for their excellent bonding with cement, superior weldability, excellent bendability and corrosion, fire and earthquake resistance qualities. Corrosion resistance is one of the key features required of rebars used in humid climes where the metal is prone to corrosion. All structural elements of concrete in coastal areas offer opportunities for the use of rebars. With natural disasters causing irreparable damage, earthquake-resistant bars are in demand.
Another major demand push for the rebar industry is the increasing awareness amongst buyers of a quality product which will give a strong structure.
Producers like Tata Steel, SAIL, Vizag Steel, Jindal Steel and Power Limited and JSW Steel account for a sizeable chunk of the rebars market, although a major share has been grabbed by the close to 500 other manufacturers concentrated in 16 clusters; for example, rolling mills in Mandi Gobindgarh (Punjab) and Raipur (Chhattisgarh) as well as those close to ship-breaking yards. JSPL manufactures its Jindal Panther-branded rebars out of its 1-mtpa facility in Patratu, Jharkhand.
JSW Steel’s flagship facility at Vijayanagar in Karnataka is not just one of the largest TMT bar mills in the country with a production capacity of 1 MnT per annum but is also regarded as an institute of steel-making technology. The company’s products have found application in key infrastructure projects such as metro rail, airports, atomic power plants and expressways. The Long Products Division of Tata Steel is the biggest rebar player in the country. Backed by superior process control and capabilities in product innovation, the company has replaced its Fe415 grade with Fe500 grade rebars, thus leading to an 18% saving in steel consumption by weight for consumers.
“The demand for TMT bars is well spread out across the country. Annual consumption is almost 25 MnT and will shortly increase by another 5-10 MnT in future due to the government’s thrust on infrastructure building and affordable housing,” said an official at JSW Neosteel. “The BIS being the certifying and enforcing authority, must play a significant role in setting up more testing facilities at various locations, particularly in the vicinity of industrial clusters like Mandi Gobindgarh, Ludhiana, Raipur, Ahmedabad, Ghaziabad, Bhavnagar, Jaipur, Durgapur and Coimbatore. More and more units must be persuaded to get BIS licenses for production of TMT bars. This applies to steel exporters to India also.”

What Secondary Producers Say
However, many TMT producers, whose manufacturing route is overwhelmingly IF, point to certain discrepancies in the BIS certification scheme. First, the scheme requires a laboratory to be maintained by all manufacturing units that should be suitably equipped where different tests shall be carried out in accordance with proposed methods.
However, there is no mention of any list of equipment (for example, spectrometer) which is necessary to be kept in the lab. Many manufacturers opine that standard analysis to ascertain the levels of carbon, manganese, suphur and phosphorous through chemical testing is routinely conducted in almost every furnace.
Secondly, the certification scheme mentions the necessity of ladle analysis, with the official document stating that two samples need to be taken for ladle analysis (one at the start and the other at the end of pouring). This, however, does not mean the entire heat needs to be poured in a ladle but only the quantity sufficient to check the chemical composition of a sample.
Moreover, so far as de-sulphurisation is concerned, IF equipment manufacturers feel charging of the de-phos compound directly into the IF is not an ideal solution due to the problem of low lining life leading to low furnace availability, high volume of slag and lower yield.
“It is better to treat the metal in a separate de-phos station after tapping from IF and then treating it in an LRF for adjustment of temperature and chemistry. Siemens VAI and Electrotherm supply the de-phos station for this purpose,” said a senior Electrotherm official.

Why TMT?

Compared to steel bars of yesteryears, TMT bars are manufactured using the latest Tempcore technology to ensure durability. The process was developed in the 1970s for making high-strength, weldable rebars from mild steel without adding costly alloying elements. What are their advantages? TMT bars:

  • Have a special WINGRIP rib design that enhances their quality
    and bonding with cement.
  • Are earthquake-resistant and have a high elongation point and
    can easily elongate without compromising their actual
    measurement or quality. Elongation is a TMT bar’s ability to
    elongate or deform before it is damaged. Greater the
    elongation, stronger the building! This quality makes them
    perfect for use in earthquake-prone areas.
  • Have high elasticity. The soft ferrite-pearlite core of the
    bars gives superior bendability. These can be easily bent and
    moulded into any shape.
  • Are highly ductile and have a super-strong surface layer
    which help TMT bars withstand fatigue for long.
  • Are available in a number of grades such as Fe 415/500/550/600.
    These bars are much stronger than conventional steel bars and
    can give up to 20% stronger concrete structure with the same
    amount of steel
  • Are resistant to corrosion. In construction projects, TMT bars
    are exposed to water and moisture for long. In case of
    conventional steel bars, such exposure results in rusting.
    However, anti-corrosive properties of TMT bars extend their
    lifespan. This feature also ensures safety of the structures
    where TMT bars are used as a construction material In India,
    the loss due to corrosion is approximately USD 40 billion
    annually – about 4% of the GDP.
  • Have superior weld-ability which helps architects and
    designers build innovative and creative structures without
    affecting construction quality.