INA maintenance-free spherical plain bearings have special sliding layers based on polytetrafluorethylene PTFE in the outer ring.

In descending order of performance capability, these are:

• ELGOGLIDE, the highest performance sliding layer
• ELGOGLIDE-W11, the sliding layer for low friction
• PTFE film
• PTFE composite.

These materials form the slideway, transmit the forces occurring and perform the lubrication function. Maintenance-free bearings must not be lubricated.

ELGOGLIDE

The sliding layer comprises a 0,5 mm thick layer of ELGOGLIDE, is embedded in synthetic resin and attached by a high strength bond to the support body.

1, PTFE fabric,comprising PTFE and support fibres
2, Resin matrix
3, Support fibres
4, Steel supporting body
5, Adhesive bond

The flow behaviour of the sliding layer is, in conjunction with the supporting body, almost negligible even under very high load. The adhesive bond is resistant to moisture and swelling.

ELGOGLIDE is a registered trademark and product of Schaeffler.

For differing requirements, the following are available:

• ELGOGLIDE
  the standard material for very high dynamic contact pressures
  from 25 N/mm2 to 300 N/mm2 and a long operating life
• ELGOGLIDE-W11
  the material for dynamic contact pressures from 1 N/mm2
  to 100 N/mm2 and with low coefficients of friction even at
  low contact pressures.

PTFE film

1, Plastic composite comprising PTFE
2, Supporting body
3, Bronze

The PTFE film (metal fabric material) is fixed to the outer ring curved surface

The metal fabric is made from high strength bronze and acts as a stabiliser for the sintered PTFE composite.

PTFE composite

1, Plastic composite comprising PTFE
2, Sintered bronze
3, Sheet steel

PTFE composite comprises sheet steel with bronze attached by sintering and an embedded plastic composite made from PTFE.

The composite is embedded with form fit between the inner ring curved surface and the outer steel surface.