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wilsoncheung
09-02-2012, 08:48 AM
Hello,

Anybody know about the limit of pressure drop in discharge line?

Some one told me that is 2 bar, but coolpack software recommends 3 bar as the maximum pressure drop.

What's the consideration? Discharge temperature?

Thanks!

Sandro Baptista
10-02-2012, 10:13 AM
Hi wilson,

3 bar or even 2 bar is too much!! I think we are talking about a gas compression system on a refrigerant plant, right?

Of course it will work if is inside the operating limits envelope. However the compressor will spend more energy, delivery less capacity and more wear will occur on the compressor parts. Also, as you said the discharge temperature will increase which will promote the wear and oil damage. If you accept so much pressure loss you can buy a smaller condenser and increase one or two discharge pipe sections.

Also all depends of the length of the pipe but I usual use a total pressure loss of 0,5K...0,8K equivalent temperature. The correspondent pressure depends of the refrigerant but whatever it is it is lower than 2 bar.

If I was you I would consider a value around 0,5 bar, as maximum. But this is my criterion.


Regards

Peter_1
10-02-2012, 11:18 AM
I count with the equivalent of only 1K!! As Sandro stated, your compressor will be consuming ways too much with even 0,5 bar pressure drop. The less the better is my advice.

Aik
20-02-2012, 02:16 PM
Apart from Sandro and Peter_1 recomendations, there is also factor such noise, witch partly depends on gas velocity. As regards me, I count velocity not more 16 m/s at full capacity.

Sandro Baptista
22-02-2012, 11:20 AM
16 m/s...I only use for large diameters.