Refrigeration and insulation knowledge of chiller and three systems of chiller

1. Water chiller: Refrigerator is usually used to cool the cold storage. The liquid (ammonia or freon) with very low gasification temperature is used as coolant to evaporate under the condition of low pressure and mechanical control and absorb the heat in the storage, so as to achieve the purpose of cooling. The most commonly used compression refrigerators are mainly composed of compressors, condensers and evaporators. According to the way of evaporation tube, two kinds of direct cooling and indirect cooling can be divided. Direct cooling installs the evaporator tube in the refrigerated warehouse. When the liquid coolant passes through the low-pressure evaporator tube, it directly absorbs the heat in the warehouse and lowers the temperature. Indirect cooling is that the air in the warehouse is pumped into the air cooling device by the blower, and the air is absorbed by the evaporator pipe hovering in the cooling device, and then sent into the warehouse to cool down. The advantages of air cooling are rapid cooling, uniform temperature in the reservoir, and taking harmful gases such as carbon dioxide from the storage process out of the reservoir.

2. Heat preservation of water chiller: Small-scale cold storage is usually made of sprayed color steel plate, rigid polyurethane foam or high-density polystyrene as heat preservation material, the storage has good rigidity, high strength, good heat insulation performance, flame retardant and so on. Small-scale cold storage is usually connected by eccentric hook or foamed on-site with embedded parts inside the plate wall. It is easy to assemble, dismantle and transport with good sealing. It has the advantages of small amount of construction and installation, labor-saving, good quality and quick effect. The small-sized cold storage is equipped with advanced refrigeration units. The storage capacity matches the refrigeration equipment completely, the cooling speed is fast, the electricity is saved and the energy is saved, and the operation is safe and reliable. Small-scale assembled cold storage is widely used. The temperature range of the cold storage is 5 - 23, and the special assembled cold storage can be up to - 30. It can meet the needs of different uses and is suitable for various industries and departments.

The chiller has three circulating systems, one is the refrigerant circulating system, the other is the water circulating system, and an electrical automatic control system. These three circulatory systems are indispensable.

Industrial water chiller system is operated through three interrelated systems: refrigerant cycle system, water cycle system, electrical automatic control system.

The refrigerant circulation system of industrial water chiller is that the liquid refrigerant in the evaporator absorbs the heat from the water and begins to evaporate. Finally, a certain temperature difference between the refrigerant and the water forms. The liquid refrigerant also evaporates completely into the gaseous phase, and then is inhaled and compressed by the compressor (pressure and temperature increase), and the gaseous refrigerant passes through the condenser. (air cooling / water cooling) absorbs heat and condenses into liquid. Through the expansion valve (or capillary) throttle into low temperature and low pressure refrigerant into the evaporator, complete the refrigerant cycle process.

The water circulation system is the pump responsible for pumping water from the tank to the equipment that the user needs to cool. The chilled water takes the heat away and then the temperature rises, then returns to the chilled water tank.

The automatic control system of electric appliances includes partial and automatic parts of power supply.

The power supply is supplied to the compressor, fan, water pump and so on through the contactor. The automatic control part includes temperature controller, pressure maintenance, delay device, relay, overload protection and other mutual combination to achieve root water temperature automatic start-stop, maintenance and other functions.