Hot‑rolled section steel features large‑scale output, high efficiency, low energy consumption and low cost. For this reason, hot rolling acts as the dominant production route. Below are six typical rolling methods for section steel.
1. Conventional Rolling Method
This method runs on standard two‑high or three‑high rolling mills. Pass grooves form between grooves of two work rolls. It manufactures simple profiles, special‑shaped sections and longitudinal‑rolled periodic section steel.
The required equipment is relatively simple. Most existing section steel mills still adopt this process today.
2. Multi‑Roll Rolling Method
Pass grooves consist of three or more roll grooves. It lowers negative impacts from closed grooves and reduces roll diameter difference.
This process makes economical profiles with parallel inner and outer flanges. It supports larger flange height and special‑shaped sections unavailable via ordinary rolling. It delivers better dimensional accuracy, lower roll wear, less power consumption and reduced residual stress. H‑beam production belongs to this category.
3. Hot Bending Rolling Method
First, billets roll into flat strips or near‑net shapes close to finished profiles. Subsequent passes complete hot bending forming.
Production can be done on ordinary mills or horizontal‑vertical tandem mills. It produces bent section profiles hard to make by other rolling routes.
4. Hot Rolling & Longitudinal Slitting Method
Hard‑to‑roll asymmetric profiles are first designed as symmetric sections. Small‑size products can be made as connected large‑section blanks to boost mill capacity. Afterwards, disc shears slit the work‑pieces either on‑line or after cooling.
5. Hot Rolling plus Cold Drawing / Cold Rolling Method
It produces high‑precision profiles. Finished parts gain better mechanical performance and surface quality than ordinary hot‑rolled sections. Dimensional accuracy reaches grade 3‑4, surface finish hits grade 5‑7. Products can serve directly as mechanical components.
It improves working efficiency and cuts metal loss. It fits revamped old mills well for small‑batch, multi‑variant production.
Process flow: hot roll to near‑net shape with reserved cold working allowance → pickling → alkaline washing → water rinsing → lubricant coating → final cold drawing or cold rolling.
6. Hot & Cold Roll Forming Method
Raw materials are hot‑rolled or cold‑rolled strip steel. Strip passes through rotating contoured rolls. Transverse bending deformation shapes strips into target steel profiles.