How To Choose A Compressor For Industrial Chillers

How To Choose A Compressor For Industrial Chillers

Summary:  The origin of industrial chillers, the products of some factories need high-temperature production...

  The origin of industrial chillers, the products of some factories need high-temperature production during the production process, and then need to be cooled to prevent hot hands or product stereotypes, so that the temperature of the workshop will be much higher than the outdoor temperature, then the manufacturer needs to install some Cooling equipment to cool the workshop. There are many different types of industrial chillers compressors on the market. Manufacturers need to choose the cooling capacity of the compressor according to the size of the workshop so that the cooling effect can reach the standard, save a certain amount of electricity, and improve production efficiency.

  First of all, in industrial chillers equipment, compressors are divided into scroll piston compressors, semi-hermetic screw compressors, centrifugal compressors, etc. A piston compressor generally consists of a casing, an electric motor, a cylinder block, a piston, a control device (starter and thermal protector), and a cooling system. The cooling methods of industrial refrigeration chillers include oil cooling, air cooling, and natural cooling. Linear compressors have no shafts, no cylinders, no seals, and no heat dissipation structures. The compressor of a general refrigeration chiller uses a single-phase alternating current as the power source, among which scroll compressors are generally used in water-cooled chillers and air-cooled chillers.

  (1). Small vibration and low noise. The torque of the scroll type is only 1/10 of that of the rolling rotor type and the reciprocating type.

  (2). efficient. The suction, compression, and exhaust processes of the scroll compressor are carried out continuously in one direction, so the harmful overheating of the suction gas is small, the pressure difference between the adjacent two chambers is small, and the gas leakage is small. There is no clearance volume, so there is no expansion process that causes the gas transmission coefficient to drop, and the volumetric efficiency is high, usually reaching more than 95%.

  (3). Due to the gas support mechanism, it is allowed to compress with liquid. Once the pressure in the compression chamber is too high, the end faces of the moving plate and the static plate can be separated, and the pressure can be released immediately.

  (4). Simple structure, small size, lightweight, and high reliability. The ratio of the number of parts constituting the compression chamber of the scroll compressor to the number of parts of the scroll type and the reciprocating type is 1:3:7, so the volume of the scroll type is 40% smaller than that of the reciprocating type, and the weight is 15% lighter. Because there are no suction and exhaust valves, less vulnerable parts, and flexible mechanisms with adjustable axial and radial clearances, the loss and damage caused by liquid hammers can be avoided, so the scroll compressor has high operating reliability. Therefore, the scroll refrigeration compressor can maintain high efficiency and high reliability even under high-speed operation, and its high speed can reach 13000r/min.

  (5). The machining accuracy of the vortex body profile is very high, special precision machining equipment must be used, the sealing requirements are high and the sealing structure is complex.

  (6). The cooling capacity of scroll compressors ranges from 0.75 to 15KW (excluding special models), and most of them are between 3 and 5KW. They are mostly used in small household air conditioners and commercial air conditioner systems. This type of compressor is not used for refrigeration conditions of minus 5 degrees.

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

  Low-temperature compressors for industrial refrigerators are never allowed to be used in situations where the evaporating temperature is greater than -5°C to avoid overloading the compressor motor; on the contrary, if a high-temperature compressor with the same displacement is used in the low-temperature field, the efficiency of the motor is often reduced. It is also very uneconomical to reduce the power factor and the influence of the clearance of the valve plate, resulting in a significant reduction in the cooling capacity of the refrigeration equipment and an increase in the power consumption. Scientific and reasonable design and matching composition of industrial chillers, and careful, correct, and reasonable operation control of the main operating parameters of the industrial chiller system, can make it operate safely and reliably under economical and reasonable working conditions, and at the same time. It is expected to achieve the purpose of maximum cooling capacity, minimum power consumption, and highest operating efficiency.

  For a single industrial refrigeration compressor, a simple energy adjustment method is intermittent operation, that is, when the specified temperature is reached, the compressors of the air-cooled and water-cooled chillers stop running; when the temperature rises to the specified upper limit, the air-cooled chiller The compressor of the water-cooled chiller will restart again. This method is only used for small industrial refrigeration compressors, because for compressors with a power greater than 10kW, the frequent startup of the compressor motor will cause voltage fluctuations in the power supply circuit, affecting the normal operation of other equipment. At the same time, even if the compressor is not very frequent The repeated start of the machine will always cause fatal damage to the industrial refrigeration compressor. When choosing a chiller compressor in the design of industrial chillers for low-temperature chillers, the requirements for the production temperature of the refrigeration equipment should be considered first. Cryogenic compressor. In the piston refrigeration compressor, the difference in motor power and gas flow in different working conditions is fully considered. The medium and high-temperature compressors and low-temperature compressors with the same displacement are optimized and manufactured with different combinations of motors and valve plates.

  It is recommended that users choose the appropriate compressor or industrial chiller according to their own needs.