View Full Version : Sizing refrigeration Vavles by Kv

11-08-2012, 04:49 PM
Hello everyboy,

I discover this great website while googling for how to calculate Kv number of a valve.
I am not interested in any software, I would like to find some literature or book about it. My aim is to make my own Excel sheet.

I have not been able to find any reliable source of information for all valves: liquid line, suction line, superheated gas, etc.

Thank you very much in advanced for your help. ^^

11-08-2012, 10:47 PM
Does this help you?


11-08-2012, 11:44 PM
Thank you for your response. I found this document but I still have some doubts. This document is very usefull and I learn a lot of things about the issue. However, it is a quite general document for all valves and I was looking for somethins more especific for refrigeration.

Thank you very much anyway!

12-08-2012, 11:25 PM
OK, try this one, read page 11


18-08-2012, 09:27 AM
Dear Brian, I really appreciate your help. Do you know any book where this issue is treated deeply?
Considering the amount of books about refrigeration, it must be a book about how to size valves with kv. I have a lot of books of refrigeration and in all of them the issue is treated briefly.
I also checked Ashrae, but they use a different methodology.

Thank you very much for your help!

18-08-2012, 09:58 PM

Usually a valve supplier will give kv values, its up to you to select.
Danfoss Directcalc programme is good & gives options of each selection, as well as where valve in system is located ie gas, liquid or expansion device.

18-08-2012, 10:10 PM
http://www.samson.de/pdf en/t00040en.pdf

Ranger, this link doesn't seem to do anything useful, could you please try again, thanks.

19-08-2012, 02:00 AM
Stangely enough my link works sometimes, but your copy of mine does not?

Basically if you search for kv value of control valves & a lot of information is available.

19-08-2012, 04:48 AM
Sizing valves by Kv (or Cv) is a matter of fluids theory, related with orifice and energy conservation. Valve selection in refrigeration is a particular case of that. Please look at a couple of docs I upload , about :


Valves Sizing by Kv (http://bit.ly/Ny4FGi) link http://bit.ly/Ny4FGi (http://bit.ly/Ny4FGi)

Valves for Refrigeration Example (http://bit.ly/Ny4URO) link http://j.mp/P7djHH

Copy of docs via PM request

Josei , Eng:cool: