Air – Oil Lubrication for Work Roll Bearing to Optimise Mills Breakdown

Abstract

Bearing failure is one of the major concern in Indian Steel Industries as the failure leads to breakdown of the machine and thereby causes huge production loss. Bearing performance depends on design, selection of bearing type, lubricant and the type of maintenance practice chosen for it. In Steel industries there is not much scope to play for enhancing the bearing performance except good maintenance practice and manoeuvre with the lubricant and lubrication system. It is desired for any lubrication or lubrication system to optimise lubricant consumption without compromising the performance /life of the bearing. There are many systems which can provide lubricant with desired viscosity to the bearings. Grease is sticky, so it gets contaminated quickly. Consumption of grease is a bit higher and it does not help to increase the mill speed. The oil mist lubrication is better than grease lubrication system. But it has the problem of atomise oil droplet mix with air which creates foggy and unhealthy atmosphere in the shop/plant. The Air-Oil lubrication system sends metered quantity of lube oil in the form of oil streak through a distributor, carried by dry compressed air into bearing to lubricate it. The carrier air prevents entry of foreign particle in the lubricant and avoids lube oil contamination. It also helps in reaching the lubricant into the bearing clearance to maintain an oil film and it avoids the direct contact with rolling elements and races. Here in this work an attempt is made to enhance the performance of taper roller bearing of Cold Rolling Mill by implementing Air- Oil Lubrication system.