Survey request...

Date 01-29-2003 12:08

We are a structural fabricator and we use 5" - 7"/day. I'm not sure how that computes into a quantity. We have a 1500gal bulk storage tank. We use it primarily for Oxy-Mapp cutting and heat cambering/straightening. The gauge gets checked daily and the gauge reads in [inches of water].
Bulk Oxygen trucks deliver every two weeks.
We fabricate between 500 to 750 tons of structural steel weekly.
Is this the type of info you are looking for?
John Wright

By msulrich Date 01-29-2003 14:12

Your info is very helpful John. Thanks.
I'm not too familiar with the welding industry. When you mention, 5"-7"/day, what unit of measure are you referring to?
Then is the O2 distributed from the bulk storage tank using pressurized lines to multiple weldingstations?
Thanks.
Scott

By jwright650 (*****)

Date 01-29-2003 15:19

Yes, every fitting/welding table has two sets of torches, all hard piped into the building from a manifold that is supplied by the bulk storage tank. The gauge reads in "inches of water", that would be 5"-7" used each day, I'm not sure how to convert that to gallons or some volumetric unit that would make sense. I was assuming it refered to inches of water column(pressure, like a specific gravity). O2 has a weight of .0892/cu.ft. and a specific gravity of 1.1056 @ 0 degrees celcius. I could be wrong and probably am. Maybe someone could help us out with this. I'll check back for any other responses to this post.
John Wright

By billvanderhoof (****)

Date 01-30-2003 05:24

Inches of water is usually a pressure- the difference in height on the two tubes of a water filled manometer. 6" would be about 1/4 psi.
Bill

By dee

Date 01-30-2003 14:04

John,
I think you guys know how to relate the pressure to the physical data of the gas. Ed's got some physical data posted at weldreality.com gas section for handy reference. Note Acetylene is dissolved in acetone and consequently has a unique pressure/temperature/volume formula somewhat different from Boyle's.

I use inches of water as a vacuum standard, and according to what I was told (not specifically TAUGHT) several decades ago, understand it to be an "absolute" scale, rather than a gauge value (PSIG) which (I WAS taught) is the difference between test pressure and atmospheric (which depends on the variable barometer readings) but I have no reference to convert it to PSI which I can find (gotta be here somewhere).
In reality the meter is probably reading gauge pressure anyway and merely calibrated in inches; there should be some internal compensation for barometric variable, however.

I believe your meters, according to the scale in which they are calibrated, are approximating absolute pressure. It provides greater precision for laboratory calculations but the vessell may actually draw a slight vacuum if readings are quite near zero and the barometer is high.

Regards,
d

BTW Scott, we typically use more O2 in our shop breathing than we do welding or cutting; it's not our mainstay and the scale of our work is rather small. Sorry our field isnt the right one to be able to help your research.