Stepseal V is based on the dynamic, unidirectional Stepseal sealing concept. During the extending stroke of the rod, focusing of contact force on the unique Stepseal sealing edge creates high local sealing pressure and limits the micro fluid film formation under the seal. When the rod is retracted, the design of the full Stepseal sealing face supports hydrodynamic back-pumping of the fluid film, and so ensures leak-free sealing efficiency with low friction and long service life.
Comment: assessing the future of Britain’s road network
It seems to me, as I drive around, that a significant proportion of potholes are not actually potholes at all, but sunken grids and manhole covers....