Is it possible to calibrate/test a nitrogen pressure gauge (4000 psi max)using a deadweight tester. Just wondering what solvent safe to clean fluid residue within bourdon tube.
You can calibrate the gauge with fluid. The big problem is getting the residual fluid back out. If the gauge has a bleed hole on the end of the bourdon tube, you're in good shape. The thing is the dead weight tester will be made and cal'd on a specific fluid. You can't just randomly change that
dr
By far the best cleaning solvent is Freon; however, environmental concerns have made a lot of companies stop using it. Right now we use HFE. It cleans well enough; but, takes about 3 times as long as Freon to get a gage clean. If you have tight restrictions on gage clean levels the cleaning process itself can take nearly as long as the calibration; especially, using HFE. One other note, once a gage is introduced to HFE, it will not pass a Freon clean level. The HFE leaves some sort of residue in your entire system. I am far from being an expert; but, these are things I have come across here at the Space Center.
We use ECOLINK 2005, CFC free. Not quite as good as Freon, but
fairly close. Will cut greases & oils, also some plastics. Be careful. They have a web site.
Question: Couldn't the OP use a fluid separator and distilled water in the gauge?
you guys are great. I didn't realise that removing oil from a bourdon tube is complex. Any other suggestions ?
A fluid seperator with water is OK, but, nitrogen would be better. There are HP seperator assemblies that will support oil on one side, and gas on the other up to 15k psi, at ppm level of "balance". but you first have to ask, is the cost worth the need. DOS (sebacate)cleans nicely with alcohol, and if the gauge has a cleanout, its pretty simple stuff. much harder to adjust the linearity of the gauge. . . lol
dr
Thankfully Nitrogen is an inert gas... it does not sit around looking to explode like oxygen or hydrogen might want too......GIDEP has calibration and cleaning requirements that should be followed....I doubt anyone still uses freon to clean a gage, If they do they might have special requirements.
The main concern is system contamination.
Usually if you are testing nitrogen up to 4K PSI, you are testing gages on a regulator.
I believe you could test these safely with water.