Brief on Manufacturing Process of Hot Rolled Coil

The steel industry plays a vital role in a huge number of commercial and industrial applications. Steel plates, steel coils, steel beams, steel wire rods are a few of the many forms of the metal that have wound their way into wide-ranging applications.

Of these, hot rolled coils and sheets are used by the automobile, construction, electrical appliances, pipes, containers and many more industries. The sheets and coils come in varied standards ranging from mild-steel to high-strain bearing steel and in varied sizes and finishes depending upon the needs of the customers. A multitude of dealers and suppliers like , , , are key players in meeting the needs of the industry.

The manufacturing process of hot rolled coils starts with formation of pig iron in the blast furnace. In order to enhance its toughness and viscosity the pig iron undergoes additional processes such as:

· Hot metal pretreatment

· Converter process

· Secondary refining process

· Continuous casting

The resultant product is termed as 'slab'. The slab is subjected to heat in the reheating furnace and rolled continuously by the roughing as well as the finishing mill after which it is coiled to facilitate easy transportation. Top quality hot rolled coils are obtained through strict control of the temperature and constant checking of the roll surface during the process of hot-rolling. This ensures that the hot rolled coils are free from internal and surface defects. In today's times all the processes beginning from feeding to heating in reheating furnace to the formation of coils is controlled by computers.

The hot-rolled coils move through pickling line so that an attractive surface finish is lent to the metal. This is done by removing the surface scales which constitutes a layer of iron oxide on the coil's surface. Surface scales are removed by using hydrochloric acid after which the coil is washed thoroughly and then dried. On complete drying a coat of antirust oil is applied to them. The uses of hot rolled coils and sheets differ depending upon its type, standards and features. Because of its malleability this form of steel goes into a number of common applications which require a little 'give' in metal.

Another type of steel formed through the temperature related process is known as the cold rolled steel. This form of steel is costlier than the hot rolled coils and sheets due to the presence of certain additional properties. It is normally tougher and sturdier than hot rolled coil. The term cold rolled is applicable to sheets rather than any other forms like tubes or steel bars which are not rolled but drawn. Cold rolled sheets involve further processing to hot- rolled steel so as to lend it superior features.

When selecting materials for your project it is essential to understand the features of each form of steel so that it can be used rightly. All guidance in this regard will be given by different suppliers such as the hot rolled steel dealers, HR coil suppliers, steel beam suppliers and mild steel plates suppliers and so on.