7 Shaft seals, bearing housings, headwheels and cable pulleys, crank shafts; single and double mechanical seals with gas or liquid lubrication for sealing liquid or gaseous media; cassette-type mechanical seals; mechanical seals with confining fluid seals; mechanical seals with a flushing function; mechanical seals with leakage recirculation; mechanical seals with leakage control; all the aforesaid goods being parts of machines; mechanical apparatus and devices for storage, pressurisation, circulation and/or temperature control of fluids for use in mechanical seals; mechanical apparatus and devices, namely, buffer pressure units, fluid refill units, fluid circulation units, separators for impurities, apparatus and devices for collecting leakages; gas supply devices for mechanical seals with gas lubrication