NSK’s newly developed Water TF bearings are the result of combining special steel-melting technology used for aircraft bearing
material, and our original, heat treatment technology. Our WTF(water-tough) bearings successfully resist premature flaking under
severely contaminated conditions of water-infiltrated grease lubrication and powder debris (iron-oxide) contamination.
Furthermore, our WTF bearings have a bearing life that is three times longer than our conventional bearings.
Four Row Cylindrical roller bearings are also popular roll neck bearings providing several benefits.
First,the inner ring is separable from the outer ring and rollers which allows the inner ring to remain with the roll during grinding processes.This assures precise concentricity and negligible run-out providing for high rolling accuracy.Secondly,this design allows for greater radial load carrying and higher operating speeds.Four row cylindricals require a thrust bearing which is usually a two row taper,angular contact ball bearing,or a deep groove ball bearing depending on the thrust load present.
Two Row Tapered roller bearings are very common as the back-up thrust bearing in a rolling mill or as the roll neck in lighter duty rolling mills.Two row tapers are designed in a variety of styles for different applications.Converging bearings (TDI,TDIE,TDIS) consist of one double cone and two single cups possibly with a cup spacer.Diverging bearings (TDO,TDOD,TDOC) consist of two single cones,a cone spacer,and one double cup.