Combined cold storage is also called assembled cold storage, assembled cold storage and movable cold storage
The condensing unit for cold room is one of the main heat exchange equipment in the refrigeration system of the combined cold storage. Its function is to cool and condense the superheated steam of the high-temperature refrigerant discharged from the compressor of the combined cold storage into the high-pressure liquid. The heat released by the refrigerant in the condenser is taken away by the cooling medium. According to the cooling medium, the condenser of combined cold storage is mainly divided into the air-cooled type and water-cooled type:
1. Air-cooled condenser: in the air-cooled condenser, the heat released by the refrigerant is taken away by air. It is only used in the refrigeration system of small movable cold storage with a small cooling load.
2. Water-cooled condenser: in the water-cooled condenser, the heat released by the refrigerant in the compressor of the movable refrigerator is taken away by the cooling water. There are many kinds of water-cooled condenser, according to its shape, there are sleeve type, shell and tube type, and plate type.
Casing condenser for refrigeration of combined cold storage: one or several small diameter copper tubes (smooth tubes or low rib tubes) are sheathed in a large diameter steel tube or copper tube, and then bent into a circular or U-shaped spiral type according to the requirements of the unit layout. The refrigerant vapor enters the outer tube from the upper part, and the condensate flows out from the lower part of the outer tube; the cooling water enters the inner tube from the lower part, flows in reverse with the refrigerant, absorbs the heat of the refrigerant vapor along the way, and finally flows out from the upper part. This type of condenser is commonly used in the freon refrigeration system of the combined refrigerator and the small refrigerator with a cooling load less than 40kW.
Shell and tube condensing unit for cold room can be divided into vertical and horizontal type. The shell of vertical shell and tube condenser is a cylinder made of steel plate rolled and welded. Porous tube plates are welded at both ends of the cylinder, and heat transfer tubes are correspondingly arranged in the holes for cooling the refrigerant. It is characterized by large structures, many consumables, low cooling water flow rate, easy scaling and large consumption of cooling water, which is suitable for areas with sufficient water sources and poor water quality. The structure of horizontal shell and tube condenser is similar to that of vertical condenser. When the refrigerant is ammonia, a seamless steel tube is used as a heat transfer tube, and when the refrigerant is freon, a low rib copper tube is used as a heat transfer tube. Horizontal shell and tube condenser has a higher heat transfer coefficient and less cooling water consumption, but it has higher requirements for water quality. It is widely used in ammonia and freon refrigeration systems of large, medium and small refrigerators.