A basic requirement of an equipment operating under the pressure of a working medium is leak-tightness of its detachable joints. Disruption of leak-tightness not merely reduces production efficiency due to loss of feed material and end product, but is also a cause of environmental pollution by deleterious matters as well as of serious accidents during work with explosion- and fire-prone media. Peculiar complications arise, in particular, in cases where moving parts of machines, for example shafts of centrifugal pumps, are sealed, when, in addition to leak-tightness of the exit sections of the shaft, it is necessary to maintain the accepted efficiency of the machine and its preset operating life through reduction of the rate of wearing of the shaft in the area of its contact with the seal. Currently, face and gland seals are used to seal shafts. Each of these seals has merits and demerits: face seal precludes wearing of the shaft and simplifies servicing during operation, but requires higher precision of fabrication and assembly of its constituent parts and special selection of materials of the sealing rings; gland seal simplifies designing, reduces requirement for precision of fabrication and assembly of its individual parts, and does not require scarce seal materials but requires periodic tightening of the securing elements or even their replacement because of wearing of the stuffing material.
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