What are the tips for purchasing a screw chiller for the first time

What are the tips for purchasing a screw chiller for the first time

Screw chiller is named screw chiller because of its key component-the compressor adopts screw type. The state of the unit from the evaporator is gas refrigerant; after adiabatic compression by the compressor, it becomes a high temperature and high pressure state.

　　 1. When using a screw chiller to choose a chiller, pay attention to the conditions of the nominal working condition.

　　①The cold water outlet temperature and flow rate;

　　②The inlet temperature, flow rate and fouling coefficient of the cooling water.

　　2. When selecting a chiller, pay attention to the normal operating range of this type of unit, mainly because the current limit of the main motor is the current value of the shaft power under the nominal operating condition.

　　3. Attention should be paid in design and selection: under the nominal working condition flow, the outlet temperature of the cold water should not exceed 15℃, and the outdoor dry bulb temperature of the air-cooled unit should not exceed 43℃. If it is necessary to exceed the above range, it should be understood whether the compressor is allowed to use and whether the power of the main motor is sufficient.

　　4. The selection of chillers should be considered according to the cooling load and purpose. For refrigeration systems that operate under low load conditions for a long time, multi-head piston compressor units or screw compressor units should be selected for easy adjustment and energy saving.

　　5. When selecting chillers, give priority to units with higher coefficient of performance. According to statistics, the average operating time of chillers at 100% load throughout the year accounts for less than 1/4 of the total operating time. At the same time, the load adjustment range of the chiller should be considered when designing and selecting. Multi-head screw chillers have excellent partial load performance and can be selected according to actual conditions.