STAND FOR AMMONIA FILLING AND PROCESS OF FILLING OF ACTIVE DOUBLE-PHASE SYSTEM OF THERMAL CONTROL OF SPACECRAFT WITH AMMONIA

摘要

FIELD: equipment and technology for tightness testing. SUBSTANCE: proposed stand has filling and vent valves and tank with ammonia. Outlet of tank is linked to compressor which outlet communicates through connection main lines to filling valves of system of thermal control. There are provided high-vacuum pump unit, units for analysis of residual uncondensed gases, for ammonia circulation, for measurement of lack of tightness in mentioned valves, in system of thermal control and in connection main lines, units feeding helium, nitrogen, drain lines and control devices. Proper outlets and inlets of above-mentioned units, main and drain lines communicate through cut-off valves to filling and vent valves of system of thermal control. In accordance with proposed process system of thermal control is vacuumed together with connection main lines, units for analysis and circulation to ≤10^-2 mm Hg and specified amount of liquid ammonia is fed into it. Value of air inleakage from outside is measured and if it is less than permissible value vacuum pumping and ammonia circulation are continued in system of thermal control and connection main lines for required number of times till equilibrium concentration of residual uncondensed gases is achieved. Draining and filling with ammonia of system of thermal control and communication main lines alternate while measuring impurities in these gases. If no given impurities are detected then system of thermal control and communication main lines filled with ammonia are shut off, ammonia is drained and communication main lines are vacuumed. Growth of pressure with evaporation of ammonia in communication main lines is controlled and if value of measured pressure increase is less than permissible value communication main lines are filled with dry nitrogen and are disconnected from system of thermal control. EFFECT: enhanced reliability of filling of system of thermal control by way of reduction of share of residual uncondensed gases in it. 3 cl, 1 dwg