Welding a hydraulic reservoir frame

[weldermike]

Thank you Toby! Ditto on that. Same here do it all the time!

 

[deereman75]

Even though that would work, I would take the time and do it right. Empty the tank, purge it with co2, and get the joint as clean as you would if you were going to paint it. This will be more work, but it is less likely to fail again, and is the proper way to do it.

 

[rockinmywaypa]

I once used natural gas when brazing some refrigerant lines to prevent oxidation and scale inside. As someone already said, you just have to push out the oxygen.
I'd have to think about it some before I'd try it on the Frame/ Hyd tank. It should work fine, it just sounds scary.

are you sure it was natural gas and not nitrogen gas. I'm sure the results would be quite different.

 

[Mace Canute]

If you decide to use something to clean off the oil film, DO NOT use any chlorinated cleaner, like chlorinated brake cleaner. Even when it looks to be completely dried off the metal, enough remains to create phosgene gas when the heat of welding hits it and is enough to really choke you up if you get a whiff of it. A crack might hold quite a bit of it and would be much worse.

 

[deereman75]

If you decide to use something to clean off the oil film, DO NOT use any chlorinated cleaner, like chlorinated brake cleaner. Even when it looks to be completely dried off the metal, enough remains to create phosgene gas when the heat of welding hits it and is enough to really choke you up if you get a whiff of it. A crack might hold quite a bit of it and would be much worse.

I agree compleatly, the best chemical cleaner to use for this acording to welders handbook, is acetone. I would first use a grinder to expose the crack, and open it up a bit so that you can get it clean and get good penitration. Then use a wire wheel to get any rust, paint, or grime off. Then use acetone to get any oil film off, and make sure it is perfectly clean. Then I would purge it with co2 ( a co2 fire extinguisher would work well), and weld it with a 6011 or 6013 (depending on the thickness)

 

[yomax4]

Clean it with 80 water/ 20 dawn dish soap. Weld it with what ever. Very basic repair here.

 

[BXpanded]

are you sure it was natural gas and not nitrogen gas. I'm sure the results would be quite different.

Absolutely sure! I would have preferred nitrogen, but did not have any available. If you push out the oxygen, nothing happens inside the tube. Once it's purged you cut off the gas. What little leaks out while you are brazing the fitting is just burned by the torch. You can't even tell it's there. After brazing, you just blow the gas out with air.

BTW, some taps into existing gas mains are welded with the gas flowing to keep any oxygen from getting into the pipe and potentially causing an explosion. Called a "Hot Tap". I once worked for a company that had a crew that travelled all over the country doing hot taps. Very lucrative business although it apparently was not terribly dificult to do. The "fear factor" made it a valuable service.