How can a short-stress rolling mill prevent bearing burnout?

　　How can bearing burnout in short‑stress rolling mills be prevented? Here, we focus solely on seal failure. When a seal fails, the most serious consequence is leakage of the bearing lubricant, allowing contaminants to enter and accelerating bearing wear, ultimately leading to bearing burnout. So what causes seal failure? First and foremost is seal selection. Because rolling mills are frequently disassembled and reassembled, it is essential to use seals equipped with secondary lips, ensuring they are installed in the correct orientation to provide effective containment of lubricating oil or grease.

　　Secondly, when assembling the short‑stress rolling mill, adjust or check the roll height first before proceeding with assembly to prevent damage to the seals. Thirdly, seals should be replaced regularly and promptly if damaged. Prolonged service life can lead to clearance fits at the seal lip and the dynamic labyrinth interface; under oil–gas lubrication, this may result in oil leakage (though grease is somewhat less problematic), while contaminants such as water and iron oxide scale can enter the bearing, causing damage that shortens bearing life or even leads to burnout.

　　Rod and Housing Assembly: The draw rod and copper nuts constitute the primary load-bearing components of the rolling mill; the condition of this assembly directly affects product quality and the control of the production process. By rotating the copper nuts mounted on the draw rod, the rolling mill drives the upper and lower housings to move symmetrically, thereby enabling symmetrical adjustment of the roll gap.

　　The advantage of this adjustment method is that the rolling line remains stable and unchanged, thereby preventing rolling and quality incidents caused by misalignment between the rolling line and the pass‑centerline. It significantly reduces reliance on the skill level of rolling‑mill adjusters and simplifies the rolling process, thus helping to minimize rolling accidents and improve product accuracy. The clearance between the copper nuts, pressure rings, and sleeves mounted on the drawbar, as well as the elastic deformation of the drawbar under load, are the primary causes of “bouncing” in the mill. Eliminating this “bouncing” is a key measure for enhancing rolling stability and also an important means of improving die‑life utilization and product quality.

　　“Bounce” is typically mitigated through disc springs, hydraulics, or damping devices. Bounce is a critical parameter for assessing the operational performance of short‑stress rolling mills. The magnitude of bounce and the level of its control directly determine whether the mill can meet the stringent quality requirements of high‑end products.