Advantages and disadvantages of 5 compressors

Chillers are inseparable from compressors. There are various types and brands of compressors. Today we will talk about the advantages and disadvantages of five types of compressors. Advantages and disadvantages of 5 compressors

1.Half-sealed piston refrigeration compressor

Semi-hermetic piston compressors are more commonly used in cold storage and refrigerated markets (commercial refrigerated air conditioning is also useful, but is now used relatively infrequently).

The semi-closed piston type cold storage compressor is generally driven by a quadrupole motor, and its rated power is generally between 60 and 600 KW.

Number of cylinders is 2-8, up to 12.

Advantages:

⑴Simple structure and mature manufacturing technology;

⑵Low requirements for processing materials and processing technology;

⑶It is easy to achieve high compression ratio, so it is adaptable and can be used in a wide range of pressure.

⑷The device system is simple and can be applied to a wide range of pressure and refrigerating requirements.

OUMAL uses Bitzer semi-hermetic piston compressor and Copeland butterfly valve compressor.

Disadvantages:

⑴Big and heavy;

⑵Large noise and vibration;

⑶It is difficult to achieve high speed;

⑷Large gas pulsation;

⑸Many vulnerable parts and inconvenient maintenance;

2.Rotor refrigeration compressor

The rotor refrigeration compressor is totally enclosed, which is generally used in household air-conditioning or small refrigeration equipment. The refrigeration capacity of the compressor is not high, at 3KW~ 15KW.

Advantages:

⑴   Simple structure, small size and light weight. Compact size;

⑵ No suction valve, high speed, low vibration and stable operation;

(3) Suitable for variable speed operation, with speed ratio up to 10:1;

OUMAL uses Panasonic compressor.

Disadvantages:

⑴High requirements on system cleanliness and processing precision;

⑵The leakage, friction and wear between the sliding plate and the cylinder wall surface are relatively large, with obvious performance degradation;

⑶The speed unevenness of single-rotor compressor increases at low speed;

3.Scroll refrigeration compressor

The scroll refrigeration compressor is mainly in full closed structure, mainly used in air conditioning (heat pump), heat pump hot water, refrigeration and other fields.

Supporting downstream products are: home air-conditioner, multi-on-line, modular machine, small water source heat pump and so on.

Advantages:

⑴There is no reciprocating motion mechanism, so it is simple in structure, small in volume, light in weight, with few parts (especially vulnerable parts) and high reliability;

⑵Small torque variation, high balance, small vibration, stable operation and small vibration of the whole machine;

⑶High efficiency and variable frequency speed regulation technology in the range of refrigerating capacity;

⑷The scroll compressor has no clearance volume and can maintain high volume efficiency

⑸Low noise, good stability, high safety, relatively hard to liquid hammer.

OUMAL uses Daikin, Danfoss, and Copeland compressor

Disadvantages:

⑴High precision requirements, and the geometric tolerance is all in the micron level;

⑵No exhaust valve, poor performance under different working conditions;

⑶The working chamber is not easy to carry out external cooling, and the heat during the compression process is difficult to discharge, so only the gas with low adiabatic index can be compressed or internal cooling.

(4) Large displacement scroll compressor is difficult to realize. Due to the limitation of tooth height, large displacement diameter and unbalanced rotation mass increase.

4 Screw refrigerating compressor

Screw compressors can be divided into single-screw compressors and double-screw compressors.

It is widely used in refrigeration equipment such as refrigeration, heating ventilation Air conditioning and chemical technology.

The input power range has been developed to 8-1000kw, and its research and development field is very extensive, with great potential for performance optimization.

Advantages:

⑴Less parts and components, less vulnerable parts, high reliability, stable operation and low vibration;

⑵The efficiency of partial load is high, and it is not easy to be hit by liquid, and it is not sensitive to liquid hit;

⑶Strong adaptability of working conditions with the characteristics of forced gas transmission;

⑷Stepless regulation can be carried out.

OUMAL uses Bitzer and Hanbell compressor.

Disadvantages:

⑴High price, high machining accuracy of machine parts;

⑵High noise when the compressor is running;

⑶Screw compressors can only be applied in the range of medium and low pressure, and cannot be used in high pressure situations;

⑷Due to the large amount of fuel injection and complex oil treatment system, the unit has a lot of accessory equipment.

5.Centrifugal refrigeration compressor

The centrifugal compressor has large refrigerating capacity, which is suitable for large central air-conditioning system and petrochemical industry

Advantages：

⑴In the case of the same cooling capacity, especially in the case of large capacity, compared with reciprocating compressor unit, the large oil separation device is omitted, the weight and size of unit is small, and the floor area is small;

⑵Centrifugal compressor has simple and compact structure, few moving parts, reliable operation, durable service, low running cost, easy to realize multi-stage compression and multiple evaporation temperatures, and easy to realize intermediate cooling;

⑶The lubricating oil mixed in the centrifugal unit is very few, which has little influence on the heat transfer effect of the heat exchanger.

⑷Large gas transmission, high rotating speed, even gas supply, eliminating the disadvantages of gas with oil;

Disadvantages:

⑴It is not suitable for the situation of small flow rate and the single stage pressure ratio is low.

⑵Surging is the inherent defect of centrifugal compressor. The working condition of the same unit cannot be changed greatly, and the scope of application is relatively narrow.

⑶The centrifugal compressor can only work under the design condition to obtain the highest efficiency and easy to surge

⑷Poor operational adaptability, high gas flow rate, high friction resistance and low efficiency;