Control Valves in Helium 1

[JohnPritchard]

Has anyone had experience using control valves in a helium environment? If so, I am interested in understanding what the issues are around using standard control valves for this application. People have mentioned to me that "cold welding" is an issue in a helium environment and for this reason state that "sliding" type valves (e.g. gate valves) are unsuitable. Is this true? Also, do I need to worry about valve stem packing etc.? The kind of application we have in mind is at inlet pressures of around 90 bars, flow rates of the order of 20kg/s, outlet pressures of around 30 bars (pressure drop across valve is 60 bars) and inlet temperatures of between 100 to 200 degrees C.

 

[GGOSCO]

There are several things to consider when looking at a control valve for helium.

The stem packing configuratiuon will be your primary concern. Typically, helium is used as a test medium for stem leakage, for the simple fact that its is a very difficult gas to seal.

The issue of 'cold welding' is not unique to helium. Metals will gall and sieze when they are not chosen carefully. Many manufacturers neglect to use materials with an acceptable galling threshold and the sliding parts 'cold weld'.

If you are looking for a control valve capable of handling these conditions contact GGOSCO Enginnering at,

1272 Speers Rd. unit 4
Oakville, ON, Canada
L6L 5T9
P:905-825-2627
F:905-825-4051
sales@ggosco.com

http://www.ggosco.com

Speak to Chris and I am sure that they will be able to offer you a practical solution for your control valve needs. They have had valves tested by TUV that have been cerified to be a fraction of the EPA's acceptable leakage rates.

 

[TKCHANG]

GGOSCO,
As you mention, i am intersted in you helium test method for control valve. I know that TUV test according to Ta-Luft. It's different from EPA 21. What's your test procedure?

 

[NGiLuzzu]

TKCHANG,
if you're interested in the measurement of fugitive emissions, please go to Thread408-48808 in this forum...
Thanks, 'NGL