Shell and tube evaporator belongs to the inter-wall heat exchanger, its working process, the refrigerant evaporates and absorbs heat in the tube course of the evaporator, while the cold water flows in the shell course to be cooled. Specifically, the liquid refrigerant through the expansion valve pressure reduction into the evaporator tube, due to the pressure reduction, the refrigerant rapidly evaporates into a gaseous state, in the process of absorbing a large amount of heat. At the same time, the cold water from the evaporator shell process inlet into the shell process and the refrigerant in the tube for heat exchange, the heat of the cold water is absorbed by the refrigerant after the temperature is lowered, the cooled cold water from the shell process outlet out, so as to achieve the effect of refrigeration.

Structural composition

Cylinder: as the evaporator shell, usually made of carbon steel or stainless steel and other materials, with a certain degree of strength and corrosion resistance, able to withstand the pressure of the cold water in the shell process.

Tube bundle: composed of many metal tubes, is the refrigerant circulation channel. Tube bundle generally use copper alloy or stainless steel tube, these tubes have good thermal conductivity and corrosion resistance, can effectively transfer heat. There are various ways to arrange the tube bundle, the common ones are square triangle arrangement and square arrangement, etc. Different arrangements will affect the flow state of cold water and heat transfer efficiency in the shell process.

Tube plate: the tube plate is located at both ends of the cylinder, used to fix the tube bundle, and will be separated from the tube course and shell course. There are many tube holes on the tube plate corresponding to the tube bundle, and the two ends of the tube bundle are inserted into the tube holes and connected together with the tube plate through expansion and welding to ensure the sealing of the tube and shell processes.

Folding plate: installed in the shell process, used to guide the cold water in the shell process is folded flow, increase the flow rate of cold water and process, so as to improve the efficiency of heat transfer. Folding plate generally adopts the shape of bow or disc - circular, etc., and its spacing and quantity will be reasonably determined according to the design requirements and heat transfer performance of the evaporator.

Inlet and outlet tubes: Used to connect the inlet and outlet tubes of cold water and the inlet and outlet tubes of refrigerant respectively. The position and size of the inlet and outlet tubes are designed according to the specific structure and process of the evaporator to ensure that the cold water and refrigerant can enter and exit the evaporator smoothly.

Features

High-efficiency heat transfer: Shell and tube evaporator has a large heat transfer area and good heat transfer performance, which can effectively realise the heat exchange between the refrigerant and the cold water, and improve the refrigeration efficiency of the refrigeration system.

Compact structure: its structure is relatively compact, covers an area of small, suitable for a variety of different sizes of refrigeration systems, especially in places with limited space has a greater advantage.

High reliability: the evaporator cylinder, tube bundle and other main parts are made of high-quality materials, with high strength and corrosion resistance, able to operate stably for a long time under the harsh working environment, high reliability.

Easy to maintain: shell and tube evaporator structure is relatively simple, easy to maintain. In the process of operation, if found to have leakage, clogging and other problems, easy to overhaul and cleaning, reduce the maintenance cost and downtime.

Application areas

Central air-conditioning system: in the central air-conditioning system of large shopping malls, office buildings, hotels and other places, shell and tube evaporator is one of the core components of the chiller, which can provide low-temperature chilled water for the air-conditioning system to achieve the cooling and regulation of indoor air.

Industrial refrigeration system: in the chemical industry, pharmaceutical industry, food processing and other industrial fields, many production processes need to be carried out in a low-temperature environment, shell and tube evaporator can be used to cool process water or other media, to meet the refrigeration needs of industrial production.

Cold storage: in the refrigeration system of cold storage, shell and tube evaporator is used to cool the air or cooling medium inside the cold storage, to maintain the low temperature environment inside the cold storage, to ensure the quality and safety of the stored goods.