In the metalworking rolling process in hot and cold rolling mills, heat is generated by friction and deformation in the mechanical forming of the rolling stock. As a result, efficient cooling of the rolls as well as the surrounding roll area is essential for the forming process in order to ensure stable roll temperatures and effective heat conversion or removal. The aim is thus to provide a uniform homogeneous cooling across the roll width with a uniform, acceptable thermal distribution.
The fundamentals for efficient and economical roll cooling are an optimized nozzle and header arrangement. In the process of rolling the most significant aspect is the generation of heat through friction and deformation in the roll bite.
The most important aspects are:
Because of the current demands on mills to process much lighter exit gages from increased incoming hot strip thickness, much larger reductions are necessary on individual mill stands, such high reductions at a nominal width result in a larger area of contact with corresponding higher rolling force, friction and heat generation.
These high reduction schedules combined with the requirement to produce widening range of material cross-sections with a more diverse range of softer and harder materials also result in increasingly greater challenges in the control of roll temperature and the effective transfer/extraction of heat.
Establishing a uniform homogenous cooling across the rolling width with a uniform and acceptable thermal distribution (no gradients) is the ultimate goal as regards cooling and assures that the universal problem of post cooled shape after recoil is minimized. A well designed, cooling
system in good operating condition will achieve several important objectives
Whether hot rolling or cold rolling – Lechler offers nozzles and systems to increase quality and efficiency.
Systems and valves for selective roll cooling. The Lechler SELECTOSPRAY system can be operated in conjunction with any of the shape control systems currently available. The nozzle / valve zoning of the SELECTOSPAY system is matching the zoning of the shape roll.
For a higher product quality and productivity of a rolling mill, the roll cooling systems are crucial when it comes to process modifications. Lechler here supports you with thermal studies.