GB352528A - Improvements in or relating to evaporator coils for refrigerating apparatus - Google Patents

Abstract

352,528. Refrigerating. LIGHTFOOT REFRIGERATION CO., Ltd. and NOLCKEN, W. G., Bush House, Aldwych, London. April 7, 1930, No. 11030. [Class 29.] Compression systems.-In a system with a flooded evaporator and employing a refrigerant such as methyl or ethyl chloride, ir which the lubricant is soluble, the refrigerant is evaporated in successive stages at progressively increasing temperatures ir order to separate the lubricant. The evaporator may consist of a header a communicating through pipes d, e with the condenser and the suction side of the compressor respectively and having compartments connected in series by U-shaped evaporator tubes. The heat-absorbing capacity of one leg of each U-tube is increased by fins and/or by heat insulating the other leg. The concentration of the lubricant increases towards the last compartment of the header from which it is entrained and carried to the compressor by the vapour passing through slots in the pipe e. In modifications, the header is formed of a number of smaller headers connected in series by the U-tubes and a number of such evaporators at different temperatures may be connected in series. A cold accumulator n, Fig. 3, containing a low freezing-point solution, e.g. a solution of sodium chromate, may be arranged above the evaporator. The liquid refrigerant flows from the condenser through a finned pipe l traversing the cold accumulator to the inlet pipe d of the evaporator. When the compressor is shut off, vapour rises from the evaporator into the pipe l wherein it condenses and trickles back to the evaporator. The expansion valve described in Specification 324,957, [Class 29, Cooling &c.], may be used in the system.