The development of improved contact seals for motionless joints is essential for hydraulic drives of machine tools, automatic lines, industrial robots, and other machines associated with increase in pressure, reliability, environmental safety, and so on. Accord� ingly, many companies around the world are conduct� ing research on improved seal designs and new struc� tural and sealing materials with specified physicome� chanical and chemical properties [1]. In terms of effectiveness, seals are classified as absolutely hermetic (without leakage of the working fluid) and nonhermetic (with estimates of the leakage with a certain period). The necessary and sufficient condition for seal fail� ure is disruption of the specified degree of sealing. The factors responsible for such disruption may be divided into three groups. (1) manufacturing tolerances on seal construction and machining conditions; manufacturing errors due to failure to comply with the documentation; the use of unconditioned materials; poor quality control of the seals during production; (2) disruption of the specified operating condi� tions; negligent operation; failure to comply with the operational rules in the documentation; (3) design and technological errors whose discov� ery, prevention, and elimination requires profound knowledge of the physicochemical processes in the seals, study of the dependence of these processes on the relevant factors, and awareness of all possible oper� ating conditions during the design process. The seal design must correspond completely to specified operating parameters and ensure maximum durability. The influence of technological factors on seal operation is complex but the key factors are the properties of the materials and the geometry of the contact surfaces. In the design of seals, the operating conditions of the equipment are taken into account: the aggressive� ness, temperature, pressure, and speed of the working fluid; the required operating time; the durability of the seal; and the permissible leakage. Despite some accomplishments in theoretical and practical aspects of seal design and operation, the cre� ation of reliable seals with the required performance