Selection of water-cooled water pump:
The pump is generally centrifugal, so it is a problem to determine its flow rate and head.
Determination of pump flow:
We can use the chiller as a system to calculate the energy balance. The heat entering the system is: the cooling capacity plus the motor power, the heat from the cooling water removed from the system and the heat released in the environment, and is sent to the environment. According to the process requirements (inlet water temperature and outlet water temperature), the flow rate of circulating water can be determined. For example, the total cooling capacity of a centrifugal chiller and a screw chiller is 2637+1231=3947KW. The motor power is: 467+256=723KW, and the total amount of heat (cold) generated by 4670KW is removed. If the cooling water is changed from 37°C to 32°C according to the design requirements, the heat is taken out. The amount of water should be: 4670 ÷ 1.163 × 1000 ÷ (37-32) = 803.1m3 / h, (1.163 is the conversion coefficient of kW and KCal), so the flow rate of the pump should be determined, generally consider the operation of the two pumps, one pump standby The way to benefit is not to run during the high temperature period.
The second is the lift of the pump, which should be based on the flow rate of the water in the pipe (determined by the pipe size) and the length of the pipe, the local resistance (the condenser in the chiller (can be found in the specification), the control piece calculates the resistance loss, due to Cooling water is a circulation system, regardless of the high position difference, just add the high position difference of the cooling tower. The flow rate of the pipeline can generally be about 1m / s, you can press: (pressure drop per meter of pipe pressure MPa / m) i = 0.0000107 × V × V ÷ d ^ 1.3 formula is calculated, where V is the average flow rate (m / s), so the lift of the pump is also determined.
The above calculations are a bit cumbersome, and sometimes they are quite different from the actual ones. The company has several options to choose from:
1, small water cooler
DC40-2470 This pump is very commonly used. It is commonly used on small chillers. Voltage DC 24V, power 28W, head 7M, flow rate 600L/H, this pump can be equipped with water shortage protection function.
2, medium water cooler
DC50E-24150S can be used with large water coolers, and other similar models can be selected. This pump voltage 24V power can be up to 86W head 15M flow 1200L / H (and 1500L / H). This pump is recommended to select the speed control series DC50E-24150A to test the match in the previous period, because the system needs to match the power selection of the pump. The best condition is to meet the requirement. The smaller the power, the better. The customer can purchase the speed control pump and go back to adjust the potentiometer. Adjust the pump power and communicate with us to find the best parameters.
In addition, we have the following models to choose from: DC50C-2465S Voltage 24V Head 6.5M Flow 2500L/H DC50B-24130S Voltage 24V Head 13M Flow 1800L/H
3, large water cooler
If you feel that the pump pressure is still not enough, you can choose to use the pump in series so that the pump head can be doubled.