ICE PLUGGING AIR LINES
ICE PLUGGING AIR LINES
(OP)
Is it possible to form an ice plug in a 1/2"nps steel pipe carrying air at 125 psig and 70 degF by installing a nitrogen freeze jacket and throttling the air flow as required to condense and freeze the water vapour?
Our instrument air system has a diaphragm vent valve with a body/bonnet gasket leak and we would like to isolate this valve to replace the gasket. I am looking for an alternative to installing a heavy encapsulating sealant injected valve enclosure or jury rigging a rubber patch with clamps.
Our instrument air system has a diaphragm vent valve with a body/bonnet gasket leak and we would like to isolate this valve to replace the gasket. I am looking for an alternative to installing a heavy encapsulating sealant injected valve enclosure or jury rigging a rubber patch with clamps.





RE: ICE PLUGGING AIR LINES
I looked at using an ice plug on a water line we had to install a downstream isolation valve on. I talked to a couple of companies who do it, they said you need to have no flow, absolutely no flow through the line. If there was even a small water flow you couldn't get enough heat out of the system with the liquid N2 faster than the water was essentially bringing it in.
With your system, you have to have an air flow bringing in 'new' water vapor to build the plug. I think the air flow would be a problem in chilling it down (though the mass flow would be quite a bit less than for a water line) and I wonder if you did manage to freeze off most of the opening and then get the final freeze in place, how good of a plug you would have given the dynamics. I'd also be worried about cutting out and replacing a valve with 125 psig air pressure on the side of that plug.
Couldn't hurt though to talk to some companies, I can't remember who I used, likely just looked up someone using Google.
RE: ICE PLUGGING AIR LINES
RE: ICE PLUGGING AIR LINES
RE: ICE PLUGGING AIR LINES
"People will work for you with blood and sweat and tears if they work for what they believe in......" - Simon Sinek
RE: ICE PLUGGING AIR LINES
RE: ICE PLUGGING AIR LINES
Seems that you can't establish the no-flow condition.
Mock it up an try it, then you'll know.
RE: ICE PLUGGING AIR LINES
I can't understand how you have a pneumatic line to a control valve that you can't isolate. How do you operate it?
RE: ICE PLUGGING AIR LINES
BigInch, is it "snow" that causes aircraft engines to quit in flight?
RE: ICE PLUGGING AIR LINES
"People will work for you with blood and sweat and tears if they work for what they believe in......" - Simon Sinek
RE: ICE PLUGGING AIR LINES
RE: ICE PLUGGING AIR LINES