Do you know several common refrigeration compressors？ 1. Semi-sealed piston refrigeration compressor Among the various types of refrigeration compressors, the piston compressor is the first one that has come out and is still in use. For example, semi-hermetic piston refrigeration compressors are widely used in refrigeration equipment. Common manufacturers are: Emerson, Bitzer, Sanyo, Duling and other compressors.
Features of semi-hermetic piston refrigeration compressors: a wide range of pressure and cooling capacity, low material requirements, relatively mature technology, relatively simple compressor system, but fear of liquid shock. There are two common failures of semi-hermetic piston refrigeration compressors: mechanical failure and electrical failure. Common mechanical failures include wear or damage of connecting rods, crankshafts, and valve plates; electrical failures are more common in motor windings, such as short circuit, open circuit, and burnout. 2. Double rotor refrigeration compressor Double-rotor compressors are now widely used in home appliances, and the export scale of rotary compressors has been increasing year by year. The 10-year compound growth rate from 2009 to 2019 is 12.8%. Nowadays, many air-conditioning equipment choose double Rotary compressor. Features of rotary compressor: few parts and simple structure. Few vulnerable parts and reliable operation. Without the suction valve, the clearance volume is small, the gas transmission coefficient is high, the processing accuracy is high, the sealing performance is poor, and the leakage loss is large.
A friend asked Refrigeration Encyclopedia before, what are the advantages of scroll compressors and dual-rotor compressors. The advantages of dual-rotor compressors are: low-frequency energy efficiency ratio is good, high-frequency energy efficiency ratio is not as good as scroll, noise, vibration and wear are slightly larger than scroll, life is shorter than scroll, and it is difficult to make large displacement. The advantages of scroll compressors are: low-frequency energy efficiency ratio is average, high-frequency energy efficiency ratio is better than scroll, noise and vibration are small, long life, and large displacement can be achieved. 3. Scroll refrigeration compressor The scroll compressor is mainly composed of: moving disc (vortex revolver), static disc (scroll stator), bracket, cross coupling ring, back pressure cavity, and eccentric shaft. It can be divided into low pressure cavity compression and high pressure cavity.
The performance of the low pressure cavity compressor is that the entire shell is low temperature, and the shell cavity (except the exhaust port and the exhaust cavity) is low pressure; The air port and suction chamber) are both high pressure.
Scroll compressor features: stable operation, low vibration, quiet working environment, few vulnerable parts, stable operation, low noise, long life, high EER value, and are used in refrigeration and air conditioning systems. 4.Screw refrigeration compressor The screw refrigeration compressor is mainly composed of a casing, a rotor, a bearing, a shaft seal, a balanced piston, and an energy adjustment device. The screw refrigeration compressor has two screws with helical tooth grooves meshing and rotating, resulting in a change in the volume between the teeth, thereby completing the process of suction and compressor, and the cooling capacity can be steplessly adjusted between 10% and 100%. Screw refrigeration compressors are now widely used in refrigeration and HVAC equipment.
Scroll compressor features: stable operation, low vibration, quiet working environment, few vulnerable parts, stable operation, low noise, long life, high EER value, and are used in refrigeration and air conditioning systems. 4. Screw refrigeration compressor The screw refrigeration compressor is mainly composed of a casing, a rotor, a bearing, a shaft seal, a balanced piston, and an energy adjustment device. The screw refrigeration compressor has two screws with helical tooth grooves meshing and rotating, resulting in a change in the volume between the teeth, thereby completing the process of suction and compressor, and the cooling capacity can be steplessly adjusted between 10% and 100%. Screw refrigeration compressors are now widely used in refrigeration and HVAC equipment. Features of screw refrigeration compressors: the rotor and bearing strength and the degree of wear resistance are relatively high; the displacement is almost not affected by the discharge pressure; it maintains high efficiency in a wide range of working conditions; it can achieve stepless energy adjustment , Not sensitive to liquid intake. Someone asked on the okmarts.com technical group whether screw compressors are afraid of liquid shock. Many people answered that they are not afraid of liquid shock. In fact, screw compressors are also afraid of liquid shock, but screw compressors are not so sensitive to a small amount of liquid return. Large amounts of liquid return will also cause compressor failure. This requires attention.
5. Centrifugal refrigeration compressor Centrifugal refrigeration compressor is a speed compressor, which is a kind of impeller rotating machinery. It relies on the high-speed rotating impeller to do work on the gas to increase the gas pressure. Almost all refrigeration compressors with a single unit capacity of more than 1200kW use centrifugal refrigeration compressors. Generally, centrifugal compressors are used in large and extra-large air-conditioning equipment.
Centrifugal refrigeration compression features: good dynamic balance characteristics, low vibration; fewer wearing parts, long continuous operation cycle; easy to achieve multi-stage compression and throttling, to achieve a variety of evaporation temperatures; can be economically stepless adjustment; when the cooling capacity is small , The efficiency is low; it is easy to surge. The reason for surge is mentioned in a separate article on the public account of Refrigeration Encyclopedia.
