Selecting your Cooling Equipment
What do we need to know?
1. Heat Load
(a) You may know this from existing equipment or experience.
(b) By calculation:-
Water flow in litres per hour x temperature rise across machine(s)
860 = Kilowatts
(c) If you know absorbed power (kilowatt rating) of equipment to be cooled (typically hydraulic cooling) we can sometimes calculate cooling requirement.
(d) It can be calculated from volume of material being worked/cooled, the reduction in temperature required and the time allowed to cool it.
(e) Power input to heaters/process.
2. The maximum water temperature recommended by machine manufacturer to achieve safe working temperature of machinery. Also does your system have a minimum allowable fluid on temperature as some equipment cannot accept condensation forming on the work?
Remember: the lower the water temperature the higher the capital cost.
3. The maximum ambient temperature in which you will expect the cooling equipment to work in and achieve cooling duty.
Remember: the higher the ambient the greater the cost.
4. Electrical supply for chiller i.e., single phase or three phase and if being exported 50Hz or 60Hz.
5. Siting of water chiller – internal or external.
Will ambients be below zero centigrade?
Can you use glycol or do you need mechanical frost protection?
6. Noise Level
If close to operatives or adjacent to housing, what noise level is acceptable?
7. Cooling Fluids
If your system can accept tap water that is fine but some applications require deionised/demineralised water, such as laser cooling. For these applications all wetted parts need to be stainless steel.
Or, perhaps your cooling fluid is a heat exchange fluid or oil, this being the case we need to know what it is (preferably including fluid properties).
8. Cooling fluid pressure
What pressure is required from the water cooling pump?
Some machines require a minimum pressure to drive the required flow rate through the process; plus, in some instances there may be a long pipe run which offers its own pressure losses.
9. Special signals / warnings / controls
10. Size restrictions
Are you limited to space on site?