Commonly used chillers are classified into piston type, screw type, centrifugal type, and scroll type chillers according to the type of refrigeration compressors used. Their evaporators and condensers generally use shell-and-tube heat exchangers, the throttling device uses thermal expansion valves, the refrigerant is freon, piston type, screw type, centrifugal type and scroll type R22 or R134a, and the operation control adopts full Automatic control with multi-level energy regulation.
The cooling capacity of water-cooled screw chillers is generally 125-1800kw, and most compressors use semi-closed screw.
The centrifugal chiller has a large single-unit refrigeration capacity, the cooling capacity is generally greater than 1000kw, the floor space is small, the energy consumption is low, and the reliability is high. It is mainly used for office buildings, hotels, theaters, shopping malls, hospitals, etc. that require large and medium cooling capacity.
Under normal circumstances, most manufacturers will use high-efficiency condensing heat transfer tubes, multi-head spiral ribs on the outer surface of the tube and spiral protrusions to improve the heat transfer coefficient and heat transfer capacity. The internal structure optimization design greatly improves the anti-corrosion and anti-fouling ability of the condenser, and fully exerts the heat exchange effect of the condenser, thereby ensuring that the chiller reaches a higher performance level. Safety valves, bleed valves, etc. are also installed on the shell-and-tube condenser to ensure the safety of the shell-and-tube condenser and the convenience of cleaning and maintenance.