INA ZKLN2557-2RS Schrägkugellager (25x57x28)

As an axial angular contact ball bearing, this bearing carries high axial loads at elevated speeds, e.g. for ball screws. The mounting dimensions are 25x57x28 mm and the weight is 0.354 kg; technical details beyond these are shown in the specification table. For feed and positioning axes in a machining environment, this version combines axial stiffness with lasting lubricant retention.

The contact angle of the ball row deflects the load line at an angle to the bearing axis and delivers the high axial capacity and stiffness for which this design is used on ball screws and feed axes; that stiffness is only established once the adjusted set is preloaded. The contact seal on both sides bears against a counterface and closes the rolling chamber against chips, coolant and fine dust — media that are permanently present at a machining tool and would overwhelm non-contact screening.

The sealing contact produces an additional frictional torque and positions the permissible speed below that of the open version; in return the grease fill remains in the bearing over its service life and relubrication is not required within the intended operating window. Standard bearing steel is through-hardened and provides raceway hardness and dimensional stability at normal operating temperatures. For the design, axial force, preload, speed and the contamination level of the environment should be assessed together.