Can I weld to a compressor tank

[Gittyup]

Wow! Amazing how this little question has started quite a conversation. Didn't expect. I can weld good enough that my welds are strong, if not always pretty, and I know how not to blow a hole in thin metal. But, I'm not going to chance it here.

I came up with a way to attach some unistrut between the axle shaft and the top handle. I'll mount my reel to that, along with a filter and lubricator. It won't be a pretty thing, but it'll function quite well. Just gotta be careful when welding the heavy unistrut to the thin metal tubing that forms the handle. I might also add a small u-bolt too. At the axle shaft, I'll simple cut a slot in the unistrut for the axle shaft. Let it rest on the shaft and tack weld it.

I want the complete rig to be mobile so I can take it to my barn or use it in my garage. That is why I don't want to mount the reel to the wall.

 

[greenmule]

Tom,makes sense how that works,just never heard of a hydro test done in that fashon[well,it wouldn't be a hydro test,it would be pnematic test really].
The way power plant boilers,pipelines,and anything else I been involved in are tested,is you put a vent in high spot,pump water in low spot,when water comes out high spot,you close valve and keep pumping generally to 1 1/2 times design pressure,hold for a cerain period,check calibrated gage or dead weights,etc,etc,
May be at nassa they do a test like that,don't know.
Bet somebody was right most of these cheapo's ain't even to asme 8,so probably an air test at 50 lbs of some sort.probably not even that.

 

[mbohuntr]

Good idea gittyup, there's not much room for error on a thin 150 psi tank. No, it's not a 3000 psi cylinder, but imagine it letting loose in your car, or when your or a neighbor kid has their hands on it. I've been certified quite a few times, and i'd never do it. Way too much liability.

 

[greenmule]

gittyup,no,thanks for that question,led to alot of good stuff. But yeah,I wouldn't weld on the compressor air tank either,

So whats your next one,can't wait!

 

[greenmule]

Tom,do you put air in the tank thats in the tank,or do you put water in the tank?

Cause if you put water,than it would be a hydro,under the hydro.

 

[Gittyup]

OK. A follow-up question: My welder has a chart for setting the current and feed speed based on metal thickness and composition. But what setting do you use when the parts to be welded are of drastically different thicknesses?

Another question: How or can you weld aluminum to steel?

Obviously, I'm new at this welding thing.

 

[greenmule]

You just do the best you can there gittyup,turn it up.

 

[tommu56]

Tom,do you put air in the tank thats in the tank,or do you put water in the tank?

Cause if you put water,than it would be a hydro,under the hydro.

Water goes in side Don't ask me why I use to have my scuba cylinders done and a friend did them while I was there.

I don't think most air compressor tanks are done under water.

We had a deairartor (part on a steam system) at work modified to get to the nozzles that were malfunctioning and that modification was engineered by and engineer and welded by a certified welder and a new asme plate was welded on to amend the change and we had to pump it up to 150% of working pressure which was only 30 psi tested to a whopping 45 psi.

But at 10' diameter that would be 508,938 lbs of pressure on that 10ft area.
I wouldn't want to be around if it came apart.

As a comparison a scuba cylinder at 6" diameter would have about 84,823 lbs at 3000 psi

tom

 

[greenmule]

Well,thick to thin/thin to thick,if you got her set to hot,you'll burn up the thin,so its just practice on something like that[depends on how thick to thin],but you put your puddle on the thick mostly,and let it come onto the thin,and depending on how thin,you gotta go fast,you'll just have to experiment,

Aluminum to steel,can't do it far as I know,you would need one or two middle metals in there somewheres. Braze/solder,would be the thing to do there I think[or screws].

Come on there men,tell him how to weld alumn. to steel.

 

[greenmule]

Tom,scuba tank tests are done under water with pressureized water!,I knew this was something different.
yeah,psi and gas stuff= big bad boom,thats the reason for hydro,it might kill you if your standing next to it,but it won't blow the whole damned building up.