Compressed forms of refrigeration system include single […]
Compressed forms of refrigeration system include single-stage compression and two-stage compression. Single-stage compression is the refrigeration system will be the compressor, condenser, throttle, evaporator four major components, once connected with a pipe to form a basic single-stage compression system. The refrigerant in the system after compression, condensation, throttling, evaporation of the four processes, you can complete a refrigeration cycle. Two-stage compression can be divided into single-stage two-stage compression and with two-stage compression. Single-stage two-stage compression is the use of a refrigeration compressor for two-stage compression, with a small footprint, the system is simple, short construction cycle, easy operation and management, etc., for large and medium-sized Refrigerated Cold Room , but not under working conditions Change flexible adjustment. With group double-click compression is composed of several single-stage compressor to complete high and low pressure level compression. Refrigeration compressors used to match the group should try to choose the same series, so easy to exchange parts.
Determine the main compression system based on the pressure ratio, that is, under certain conditions, the system condensing pressure and evaporation pressure ratio. When the pressure ratio is less than or equal to 8, ammonia system should be used single-stage compression; pressure ratio is less than or equal to 10, the fluorine system using single-stage compression. When the pressure ratio is greater than 8, the ammonia system should be two-stage compression; when the pressure ratio is greater than 10, the fluorine system uses two-stage compression. According to the relevant calculations, we design the cold storage should be used in two-stage compression.
Refrigeration compressors include piston compressors, screw compressors and centrifugal compressors. Piston refrigeration compressor technology is mature, good thermal performance, is currently widely used in refrigeration system. However, this type of compressor, vulnerable parts and more parts and more management and maintenance more trouble. Screw refrigeration compressor is a volume rotary compressor, simple structure, small size, less vulnerable parts, long maintenance cycle, stable and reliable operation, easy maintenance, and thus a variety of refrigeration devices are more widely used; Especially in the limited space, you need to move the cooling system. However, due to the high machining accuracy, the manufacturing is more complicated, the noise is larger and the efficiency is lower, which is limited by the use. Centrifugal refrigeration compressor is oil-free compression, mechanical wear and tear, light weight, and can achieve automatic control, for larger cooling capacity of the refrigeration unit; as a single refrigeration capacity can not be too small, limiting the use of centrifugal compression Machine manufacturing and processing of high precision, maintenance difficulties.