lubricated with plastic lubricants* The break-away torque of the ring with guides at —35*C was an acceptable value; however, when temperature decreased, the component of the force of friction increased proportionally to speed. Although docking usually occurs normally at —50*C, the APDAs were qualified for work to -35'C. Friction in the mechanisms at negative temperatures (— 50*C and lower) may be decreased by using anti-friction coatings or self-lubricating materials; however, their use requires a longer creating and testing time. At present, solid anti-friction coatings based on molybdenium disulfide are used, and the technology of applying them to the surface of parts is relatively simple. Working capacity is maintained over a substantially larger range of temperatures than plastic and liquid lubricants. However, these coatings have a short lifetime at small acceptable specific loads; thus they have been used in the following units of the docking device: 1) contacting surfaces of the buffer and guide elements; 2) mechanisms with a small number of actuations (latches, etc.); 3) single use elements (in the pyrotechnics) and some other elements. A11 of these lubricants are used in mechanisms which are inside and outside the spacecraft. The friction of the placement of units in closed casings has a favorable effect on their work. Outgassing from materials, especially plastic, creates an “atmosphere* in them for a long period of time, with a residual pressure of 1-10 pascal, which helps preserve the lubricants and prevents the removal of adsorbent layers of gas on frictional surfaces without lubricants, for example, electrical contacts. 3.8. Provision of the Temperature Conditions of Docking Assemblies To insure the working capacity of the docking device the temperature of its elements should be within certain limits. Frequently the mechanisms are created for work in a range of temperatures +-150C. Lubricants and resin seals are most sensitive to heating and cooling. In nonworking mechanisms, as a rule, unacceptable or irreversible changes occur in a wider range of temperatures. The temperature of docking device elements is defined by the thermal
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