Working Principle of Rough Rolling Mill

Sep 22, 2023

The forming of steel products is mainly completed by rolling in a rolling mill. Depending on the temperature during rolling, there are hot and cold rolling. Hot rolling is a high-temperature deformation process, and the processing temperature is generally above 1000°C. The metal has better plasticity at this temperature and can be easily pressed into the desired shape. Cold rolling does not require high-temperature deformation. It is a rolling process that presses and deforms metal at room temperature.

During hot rolling, the metal has high plasticity and low deformation resistance, which greatly reduces the energy consumption of metal deformation. Hot rolling mills usually consist of roughing mills and finishing mills. Today, we will introduce the rough rolling mill.

Roughing mill is an important piece of equipment in the steel rolling process and is mainly used to roll the preliminary shape and size of steel. The following is an overview of how a roughing mill works:

Rolling stock introduction: The starting work of the rough rolling mill starts with introducing the rolling stock. The heated metal billet is fed into the front end of the rolling mill, passes through a series of guide wheels and supporting devices, and enters the roll area.

Rolling process: The roll is the roughing mill's core part, consisting of two or more horizontally installed rollers. During the rolling process, the upper roller applies downward pressure, causing the metal blank to be compressed between the two rollers to obtain the desired shape and size. This pressure is transmitted through a hydraulic system or a mechanical lever system.

Metal flow and deformation: During the rolling process, the metal blank undergoes plastic deformation under high pressure, gradually becoming thinner and longer along the rolling direction. This deformation is continuous until the desired thickness and width are reached.

Finished product output: After the metal billet is rolled into the required shape and size, it is transported to the downstream finishing mill or other processing equipment. During the output process, the rolled piece must pass through a series of guide wheels and support devices to ensure stable output.

Rolling control: The operation of the roughing mill requires precise control, including adjustment of rolling force, temperature control, metal flow monitoring, etc. These control measures ensure rolling stability and product quality.

Automation and intelligence: Modern rough rolling mills are usually equipped with various automation and intelligent systems, such as online monitoring systems, control systems, fault diagnosis systems, etc. These technologies can improve production efficiency, reduce energy consumption, and improve product quality.

The roughing mill applies pressure to plastically deform the heated metal blank to obtain the desired shape and size. Metal flow is controlled throughout the process to ensure the rolled product meets requirements. The operation of the roughing mill requires high-level operating skills, advanced automation, and intelligent technical support. It is also inseparable from the support of high-quality bearings. For example, the pressing device requires the use of pressing bearings. Four-row cylindrical roller bearing and double-row tapered roller bearings are usually used on support rollers to bear radial and axial loads.

The selection of bearing type, bearing accuracy and clearance, and bearing lubrication will all play a key role in the performance of the bearing and even the performance of the rolling mill. Therefore, we must pay attention to the selection of rolling mill bearings. If you have any questions, don't hesitate to contact FV engineers.

The picture below shows the double-row tapered roller bearing M270730/10CD and the Screw-down bearings customized by our FV for steel mill customers.