Types of gas compressors

The a lot of accepted compressors acclimated in chillers are reciprocating, rotary screw, centrifugal, and annal compressors. Each appliance prefers one or accession due to size, noise, ability and burden issues. Compressors are about declared as getting either open, hermetic, or semi-hermetic, to call how the compressor and/or motor is anchored in affiliation to the refrigerant getting compressed. Variations of motor/compressor types can advance to the afterward configuations:

Abstruse motor, abstruse compressor

Abstruse motor, semi-hermetic compressor

Attainable motor (belt apprenticed or abutting coupled), abstruse compressor

Attainable motor (belt apprenticed or abutting coupled), semi-hermetic compressor

Typically in hermetic, and a lot of semi-hermetic compressors (sometimes accepted as attainable abstruse compressors), the compressor and motor active the compressor are integrated, and accomplish aural the refrigerant system. The motor is abstruse and is advised to operate, and be cooled by, the refrigerant getting compressed. The accessible disadvantage of abstruse motor compressors is that the motor drive cannot be maintained in situ, and the absolute compressor have to be removed if a motor fails. A added disadvantage is that burnt out windings can alloy accomplished algidity systems acute the arrangement to be absolutely pumped down and the refrigerant replaced.

An attainable compressor has a motor drive which is alfresco of the algidity system, and provides drive to the compressor by agency of an ascribe shaft with acceptable gland seals. Attainable compressor motors are about air-cooled and can be adequately calmly exchanged or repaired afterwards degassing of the algidity system. The disadvantage of this blazon of compressor is a abortion of the shaft seals, arch to accident of refrigerant.

Open motor compressors are about easier to air-conditioned (using ambient air) and accordingly tend to be simpler in architecture and added reliable, abnormally in top burden applications area aeroembolism gas temperatures can be actual high. However the use of aqueous bang for added cooling can about affected this affair in a lot of abstruse motor compressors.

edit Reciprocating compressors

Main article: Reciprocating compressor

Reciprocating compressors are piston-style, absolute displacement compressors.

edit Rotary circling compressors

Figure 3: Circling Compressors

Main article: Rotary circling compressor

Rotary circling compressors are aswell absolute displacement compressors. Two coaction screw-rotors circle in adverse directions, accoutrement refrigerant vapor, and abbreviation the aggregate of the refrigerant forth the rotors to the acquittal point.

edit Centrifugal compressors

Main article: Centrifugal compressor

Centrifugal compressors are activating compressors. These compressors accession the burden of the refrigerant by imparting acceleration or activating energy, application a alternating impeller, and converting it to burden energy.

edit Annal compressors

Figure 4: Operating assumption of a Annal Compressor

Main article: Annal compressor

Scroll compressors are aswell absolute displacement compressors. The refrigerant is aeroembolism if one circling orbits about a additional anchored spiral, creating abate and abate pockets and college pressures. By the time the refrigerant is discharged, it is absolutely pressurized.

edit Others

Main article: Diaphragm compressor

Main article: Axial-flow compressor

Main article: Diagonal or mixed-flow compressor

Main article: Aqueous ring compressor

Main article: Roots blower

edit Compressor Lubrication

In adjustment to anoint the affective locations of the compressor, an oil is added to the refrigerant during accession or commissioning. The blazon of oil may be mineral or constructed to clothing the compressor type, and aswell called so as not to acknowledge with the refrigerant blazon and added apparatus in the system. In baby algidity systems the oil is accustomed to broadcast throughout the accomplished circuit, but affliction have to be taken to architecture the pipework and apparatus such that oil can cesspool aback beneath force to the compressor. In beyond added broadcast systems, abnormally in retail refrigeration, the oil is commonly captured at an oil separator anon afterwards the compressor, and is in about-face re-delivered, by an oil akin administration system, aback to the compressor(s). Oil separators are not 100% able so arrangement pipework have to still be advised so that oil can cesspool aback by force to the oil separator or compressor.

Some newer compressor technologies use alluring bearings and crave no lubrication, for archetype the Danfoss Turbocor ambit of centrifugal compressors. Avoiding the charge for oil lubrication and the architecture requirements and ancillaries associated with it, simplifies the architecture of the refrigerant arrangement and reduces aliment requirements.

edit Control

In simple bartering algidity systems the compressor is commonly controlled by a simple burden switch, with the amplification performed by a capillary tube or simple thermostatic amplification valve. In added circuitous systems, including assorted compressor installations, the use of cyberbanking controls is typical, with adjustable set credibility to ascendancy the burden at which compressors cut in and cut out, and temperature ascendancy by the use of cyberbanking amplification valves.

In accession to the operational controls, abstracted top burden and low burden switches are commonly utilised to accommodate accessory aegis to the compressors and added apparatus of the arrangement from operating alfresco of safe parameters.

In added avant-garde cyberbanking ascendancy systems the use of amphibian arch pressure, and proactive assimilation pressure, ascendancy routines acquiesce the compressor operation to be adapted to accurately accommodated differing cooling demands whilst abbreviation activity consumption.