Ball chain and seals

Design and version

Friction
Due to the Rexroth design with four rows of balls, 2-point contact is available in all loading directions. This reduces the friction to a minimum.
Other ball rail systems with two or four rows of balls with 4-point contact have multiple friction: due to the differential slip with lateral loading and in case of comparable prestressing without the load, the gothic raceway profile causes higher friction (depending on the raceway curvature and the load, up to five times the friction coefficient). This high friction leads correspondingly to greater heat.
Seals
Seals are use to prevent dirt, chips and coolants, etc. from working their way into the inside of he Ball Runner Block, thereby preventing reductions to its service life. For further information, see “Selection criteria/seals”.
Standard seal (SS)
Universal seals are fitted as standard in Rexroth Ball Runner Blocks. They have a uniform sealing effect for Ball Guide Rails with and without cover strips. Low friction and a good sealing effect have both been taken into account in the design. For applications where effective sealing is required.
Low-friction seal (LS)
For special requirements with regard to ease of movement.
Double-lip seal (DS)
For increased exposure to media
Front seal
For applications in environments with fine dirt or metal particles, as well as coolants or cutting fluids.
Interchangeable during servicing.
Front seals are available as accessories for mounting by the customer.
FKM seal
For applications in extreme environments with fine dirt or metal particles, as well as heavy use of coolants or cutting fluids.
Interchangeable during servicing.
FKM front seals are available as accessories for mounting by the customer.
Cover plate wiper
For use in environments with coarse dirt or chips.
Cover plate wiper are available as accessories for mounting by the customer.