| Method of Operation
The sealing effect of the U-Cup comes from the intrinsic preload of the seal body and from the compression of the seal lips during installation. In operating condition, the radial mechanical contact forces are superimposed by the system pressure. At low stroke speeds, U-Cups can tend to have a stick-slip effect due to an inadequate lubrication film formation in the seal clearance and to their material properties. This behaviour corresponds to the Stribeck curve described in the relevant literature.
Advantages
1) Good pressure-adapted sealing effect
2) Unaffected by high loads and deflections of the piston rod
3) Good resistance to clearance extrusion
4) Simple installation
5) Lower friction in the low pressure range compared with double-lipped versions.
technical drawing:
| material M-90 |
max working pressure 35 mpa |
| hardness shore A 90 |
working speed 0.03~0.5m/sec | | 
