Hot rolled steel: Versatile like no other
Product17 Apr 2022
On a very basic level, steel is manufactured in one of two ways - cold rolling or hot rolling. In the hot rolling process, red-hot steel slabs are passed between a series of rollers at high speeds and at very high temperatures, usually over 1700°F, to form thin strips of uniform thickness and strength. The steel is tempered at extreme temperatures. The result is that it can be hammered thin or stretched into wires without the risk of fracture.
Once the alloy has been deformed into the desired shape and dimension, it is cooled in a controlled manner using water sprays. The resulting hot rolled (HR) steel is “normalised” at room temperature, thus removing hardness, improving on its ductility, and overall strength. For context, cold-rolled steel is basically hot-rolled steel that has undergone additional processing at room temperature. Cooling from extreme temperature leaves HR steel with a characteristically thin, flaky surface texture and rougher feel. Typically, HR steel bars and plates feature slightly rounded edges and corners as well as modest distortions.
There are some clear advantages over others, including its cold-rolled counterpart. Cold-rolled steel has certain distinct applications and it is favoured over hot-rolled steel in those scenarios. The kind of steel MSMEs use is ultimately decided by the nature and scope of their projects.
Lower Steel Price Points
Hot rolled steel generally works out much cheaper than cold-rolled of the same grade because it requires much less processing. In cold-rolling, steel is flattened into smooth metal strips at room temperature. This is an additional process that demands quite a bit more force and energy, thus adding to the overall steel price.
High Malleability
When steel is hot-rolled at temperatures above its recrystallisation temperature (i.e., 750-1,300°F ) the material is altered irreversibly at its micro-level. HR steel owes its enhanced toughness and ductility to this process The steel that emerges from this process is highly ductile. As a result, unlike cold-rolled steel, it easily bends under great stress without fracturing or can be fashioned into various shapes and forms.
Reduced Production/Lead Time
There are far fewer processes around HR steel, it is ready for use once it is cooled to room temperature. There aren’t any major delays to speak of. In terms of ductility and ease of manipulation, hot-rolled steel is miles ahead of its cold-rolled kin. By extension, projects that make use of it will likely see faster completion.
Wide Use
It’s cheaper, easier to make, and comes in multiple grades (e.g., 304, 310S, 316L, 304L). These are arguments in favour of HR steel and what make this a popular choice for MSMEs as well as large enterprises across industries. Here’s looking at some of its major applications:
D-bars, standard joint bars, expansion joints, i-beams
Small-scale steel frames for bridge surfaces, ship decks
Automobile door hinges and truck rims
Forklift trucks, rail joint bars, tram rails
Agriculture and farm equipment components
Treads for excavators and tracked vehicles
Industrial fasteners, sheet pile connector
Pipe couplers, spigot joint, pipe fittings
Hot-rolled steel lacks the surface finish of cold-rolled steel as also the dimensional uniformity (tighter tolerance) and straightness. In scenarios where high precision is a requirement, HR steel is not a possibility. Hence it is not suited for aerospace structures with high strength-to-weight ratio, home appliances, and metal furniture with surface finishes, as well as strips, bars, and rods with precise dimensional tolerances.
So if you’re looking for hot-rolled steel coils with high-ductility and other features, contact our team at JSW One MSME. We sell steel by grade, thickness, width and, length. It’s about quietly bringing the one-click retail shopping e-commerce experience to the steel industry. Shop your products today!
The idea behind JSW One MSME is to provide MSMEs with a smooth supply and benefit from our one-of-its-kind digital experience. JSW One MSME is a consistent, flexible, and trusted steel solutions platform that supports material needs for MSMEs of all sizes.