Rotary shaft lip seals are components designed in a ring form, fitted between machine parts in

relative rotation, with the function of separating oil or grease from the inside and dirt, dust, water

etc. from the outside. The radial shaft seal consists of two main parts: A cylindrical outer covering of sheet steel (case) or an elastomer that has the requisite interference fit to seal statically against the

housing bore. 


A sealing lip made of an elastomeric material that seals dynamically and statically against the shaft. The lip has a sealing edge that is formed by molding, cutting, or grinding. It is normally .


pressed against the counter face surface of the shaft, with a defined radial load, by a garter spring. The edge of the sealing lip and the shaft counter face surface form the most important functional area of a radial shaft seal.

Radial Oil Seal type TRA are seals with completely rubber covered outer diameter and a single sealing lip. The TRA type is not recommended for use in heavily polluted environments.



Radial Oil Seal type TRA is typically used in transmission systems (e.g. gearboxes), pumps, electrical motors, and machine tools



  • Good static sealing
  • Compensation of different thermal expansion
  • Reduced risk of fretting and/or corrosion
  • Higher bore surface roughness is allowed
  • Installation in split housings
  • Modern lip design provides low radial forces



Pressure : Up to 0.05 MPa

Temperature : -40 °C to +200 °C (depending on material)

Speed : Up to 30 m/s (depending on material)

Media : Mineral and synthetic lubricants (CLP, HLP, APGL etc.)