Compressor Development Trend
Compressors, a moving fluid machine that elevating low pressure gas to high pressure gas, is the heart of the refrigeration system. It from the suction suction low temperature low pressure refrigerant gas, through the motor run a piston to compress, the exhaust pipes of high temperature and high pressure refrigerant gas, provide power for refrigeration cycle.
Thus, the refrigeration cycle of compression, condensation (exothermic), expansion, evaporation (heat absorption) is achieved. Compressor is divided into piston compressor, screw compressor, centrifugal compressor, linear compressor etc. Entry of compressor are introduced working principle, classification, accessories, specifications, and operating requirements, the compressor production, common faults, and environmental protection requirements, the selection principle, installation conditions and development trends.
The compressor is divided into the volumetric compressor and the speed type compressor according to its principle. The volume type is divided into: reciprocating compressor, rotary compressor; The speed type compressor is divided into: axial flow compressor, centrifugal compressor and mixed flow compressor.
Nowadays household refrigerator and air conditioner compressor are volume type, which can be divided into reciprocating and rotary type. Reciprocating compressor USES piston, crank, connecting rod mechanism or piston, crank, slide tube mechanism, and the rotary rotor compressor is used. On commercial air conditioning, more is centrifugal type, vortex type, screw type.
According to the application range can be divided into low back pressure type, mid-back pressure type, high back pressure type. Low back pressure type (evaporation temperature - 35 ~ 15 ℃), commonly used in domestic refrigerators, food cooler, etc. In the back pressure type (evaporation temperature - 20 ~ 0 ℃), commonly used in soda fountain, milk cooler, etc. High back pressure type (evaporation temperature - 5 ~ 15 ℃), is generally used in room air conditioner and dehumidifier, heat pump, etc.
Working principle: use on the air compressor is mainly to adjust air compressor start-stop state, by adjusting the pressure inside the storage tanks to stop to rest, let the air compressor maintenance for machine. At the time of air compressor plant commissioning, according to the customer need to adjust to the specified pressure, and then set a pressure difference. For example, the compressor to start, to storage tanks, pressure to 10 kg, stop or uninstall air compressor, air compressor when pressure to 7 kg to start again, it's a pressure difference, this process can make the compressor have a rest, to protect the role of air compressor.
The motor drives the compressor directly, causes the crankshaft to rotate and drives the connecting rod to cause the piston to reciprocate, causing the cylinder volume to change. Due to the change of pressure in the cylinder, through the inlet valve Make the air through the air filter (silencer) into the cylinder, in the compression stroke, due to the cylinder volume reduction, the role of compressed air through the exhaust valve, the exhaust pipe, one-way valve (check valve) to storage tanks, when the exhaust pressure to achieve the rated pressure of 0.7 MPa is controlled by a pressure switch and automatic stop. When the pressure of the storage tank is reduced to 0.5 -- 0.6mpa, the pressure switch automatically joins up.