Grease lubrication should be avoided, as the sealing gap cannot form a status of a hydrodynamic lubrication. The consequences are increased wear and shorter service life.
Nevertheless, the grease lubrication is to be regarded as permanent lubrication, limited only up to vmax = 3 m / s.
Relubrication with a grease gun should be avoided, since the o-rings can be pushed out of their position and destroyed by the high grease pressures, how- ever, necessarily.
A through-lubrication of the sliding surfaces is not possible, since the seal rings are loaded with pressure build-up from the inside in the closing direction.