The four most common types of refrigeration compressors in chiller units are: centrifugal, screw, scroll and reciprocating.

First, screw compressor

1. High reliability, fewer parts, no wearing parts, so it runs reliably, long life, general screw machine main head design life of 30 years.

2. Easy operation and maintenance, high degree of automation.

3. Good power balance, can work smoothly at high speed, to achieve no foundation operation.

4. Strong adaptability, with the characteristics of forced gas transmission, volume flow is almost not affected by exhaust pressure, and can maintain high efficiency in a wide range of working conditions.

5. Multi-phase mixed transport, the rotor tooth surface actually has a gap, so it can withstand the liquid impact, and can pressure the liquid containing gas, dust containing gas, easy polymerization gas, etc.

6. Slide valve flow regulation, no need to play backflow, can effectively reduce energy consumption.

Screw compressors are used in water-cooled screw chiller  and air-cooled chillers screw chiller

Two, scroll compressor

It is widely used in air conditioning and refrigeration units for its high efficiency, small size, light weight, low noise, simple structure and balanced operation.

(1) The pressure difference between the two adjacent chambers is small, and the gas leakage is small.

(2) Because the suction, compression and exhaust processes are continuous at the same time, the pressure rises slowly, so the torque change amplitude is small and the vibration is small.

(3) There is no clearance volume, so there is no expansion process that causes the gas transmission coefficient to decrease.

(4), no suction, exhaust valve, high efficiency, strong reliability, low noise.

(5) Due to the use of gas support mechanism, it is allowed to compress with liquid, once the pressure in the compression chamber is too high, the moving disk and the static disk can be separated from the end face, and the pressure can be immediately released.

(6) The inner chamber of the casing is an exhaust chamber, which reduces the suction preheating and improves the gas transmission coefficient of the compressor.

(7) The processing precision of the vortex line is very high, and special precision processing equipment must be used, and the sealing requirements are high and the sealing structure is complex.

Scroll compressors are mainly used in air-cooled chillers, but they can also be found on water-cooled chillers

Three, rolling rotor compressor

It is widely used in home appliances refrigerator and air conditioner, of which large and medium-sized rolling rotor compressor is also used in cold storage

(1). Fewer parts, simple structure.

(2). Less vulnerable parts, reliable operation.

(3). There is no suction valve, small clearance volume, high gas transmission coefficient.

(4). Under the same refrigeration capacity, the compressor is small in volume, light in weight and balanced in operation.

(5). High machining accuracy requirements.

(6). The sealing line is long, the sealing performance is poor, and the leakage loss is large.

(7). The leakage, friction and wear between the slide and the cylinder wall are large, which limits its working life and efficiency improvement.

Four, piston compressor performance analysis

In small cooling capacity applications occupy a certain market

(1). Due to clearance volume, suction and exhaust pressure loss, heat exchange between gas and cylinder wall and leakage and other factors. The actual gas transmission of the compressor is less important than its theoretical gas transmission.

(2). Due to the piston, piston ring, friction with the cylinder wall and the loss of power to drive the lubricating oil pump, the mechanical efficiency of the compressor is generally between 0.75 and 0.9.

(3). The overheating of the compressor exhaust will reduce the gas transmission coefficient of the compressor and increase the power consumption, which will lead to the excessive expansion of the piston and get stuck in the cylinder, and the built-in compressor of the closed compressor will be burned out, affecting the life of the compressor. The exhaust temperature should be below 150 ° C for R717 and R22, and below 130 ° C for R12.

(4). Due to the internal flow resistance, mechanical friction and heat exchange of the compressor, the compression process is not an isentropic process, but a variable process.

Dongguan Ice Universe Machinery Co., Ltd. (DIUM) 

 is a reliable supplier of quality industrial water cooled chiller and screw type chiller, oil type chiller, we have a big factory, and is the main suppliers of mobile air conditioner.

More industry refrigeration solutions welcome you to contact us.

Sincerely look forward to communicating with you and learning from each other.

Dongguan Ice Universe Machinery Co., Ltd. (DIUM)

service@evergrinding.com