Capacity of Cooling Towers

Are you trying to decide on a style/size of cooling tower for a known load?

Or are you trying to determine the load you need to cool? Flowrates and temperatures of your cooling water?

dear,

yes, load of cooling tower,size of cooling tower & flow rate.

Yes, I need to know about it.

Hello harihara4u:

Can you tell me what product your factory makes, and, what size your factory is and its capacity for the product you make please?

Take care...................

We need more information such as your cooling water flow requirements, allowable temperature rise across the exchangers, ambient conditions, make up water quality, allowable cycles, etc. to answer this question. There are some good sources online and also in textbooks such as Perry's.

dear,

we are producing plastic automative part.so for that purpose we are having three plastic injection molding machines & require 8 to 10 bar water pressure to chill the tools .INLET water temp. should be 10 to 15deg.c.OUTLET water temp. will be 30 to 35deg.c.

Hello harihara4u:

Thank you for some extra info', though it would be preferable to have the make of machine for ref', and the ambient temp in your factory.

You mention 'cooling towers'. It this how you have cooled your tools in the past? I would have though a simple chiller unit where the water is pumped through a heat exchanger would do the job. But I need to know the temperature of the inlet water, and, are you cooling the tool to allow extraction of the vacuum formed piece or to keep the tool cooler?

I assume you have these machine running now, is that right?

Can you please read and let me know your thought on this? You must keep talking to us and answer as quick as possible.

Please tell me what machines you have now.

Cooling towers alone will not provide what you are looking for.

Local environment conditions will determine the limiting minimum outlet temperature of your cooling towers, but it will only be a few degrees below local ambient and that's unlikely to ever be 10 Degrees. I've seen cooling towers where the outlet temperature is as high as 35 Degrees (ambient 40 Degrees and around 80%RH) and those same towers with outlet temps around 4 Degrees C (Ambient 0 Degrees and frost levels) at differnet times of the year.

Also, the temperature difference that you have nominated is purely a matter of flow rate through your tools and the heat input from the plastic material in each shot.

Cooling towers are too variable for the level of temperature control that you are looking for. You will need inside your moulding shop heat exchanger units that are actual refrigeration devices that use the cooling tower water to transfer the heat away. Usually one for each tool (Or in bigger tools, one for each water path.) so that flow rate and heat exchange can be controlled.

From a personal interest, what palstic are you moulding and what wall thickness? I'll compare to our current situation here and give some feedback.

My first impression is that your temp difference across the tool is too big, and I would guess that you are trying to cool the parts very quickly using such cold material. This could lead to significant moulded in stress, warpage and part variation as well as surface defects due to premature cooling of the material as it fills the tool.