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monkey spanners
07-05-2008, 08:08 PM
I have a small recovery bottle and two of the three welds holding the lifting hand have broken. Looking at the welds i think one of them wasn't doing anything in the first place and the handle has been moving about and hence the second weld has failed.

What do you think to getting it welded back on?

Or is it not worth the risk with it being a pressure vessel?

I hate throwing things away that can be fixed, my metal tool box for example has been welded up a couple of times, new catches put on, new handle. Its just about due its third refit as it has a couple of fatigue cracks developing:D

Jon

nike123
07-05-2008, 08:14 PM
I have a small recovery bottle and two of the three welds holding the lifting hand have broken. Looking at the welds i think one of them wasn't doing anything in the first place and the handle has been moving about and hence the second weld has failed.

What do you think to getting it welded back on?

Or is it not worth the risk with it being a pressure vessel?

I hate throwing things away that can be fixed, my metal tool box for example has been welded up a couple of times, new catches put on, new handle. Its just about due its third refit as it has a couple of fatigue cracks developing:D

Jon

Weld it, and pressure test it with water.

The Viking
07-05-2008, 09:02 PM
My first job after Uni was building steam boilers.
The babies there were pressure rated up to 30 Bar and we always welded feets/handles/lugs on to the original vessels.
(Mind you, due to H&S legislations we had to pressure test with water, in a reinforced concrete basin afterwards...)

Pooh
07-05-2008, 10:30 PM
No problem with welding as long as you get a test certificate from an authorised testing house. Personally for the sake of thirty quid is it worth it taking the hassle if anything goes wrong.

Ian

KevinRPS
07-05-2008, 10:32 PM
Weld away have done same job just remove hand valve so no presure can build up when welding, and presure test with nitrogen.

Brian_UK
07-05-2008, 11:52 PM
Just a word of caution with your pressure testing.

I know that we PT on systems up to high pressures but, on the whole, they have already been tested at the factory etc.

Please don't stand next to the bottle while you're doing it, just in case. Steel ruptures in a different fashion to copper.

monkey spanners
08-05-2008, 12:16 AM
I think its going in the bin, as pooh says not worth it for a few notes.
I've never much liked the idea behind pressure testing, basically lets see if it goes BANG! while i'm stood next to it, always seems to me a bit like a plumber checking for gas leaks with a match, BANG! "found one":confused:

Cheers Jon

Josip
08-05-2008, 11:37 AM
Hi, monkey spanners :)


I think its going in the bin, as pooh says not worth it for a few notes.
I've never much liked the idea behind pressure testing, basically lets see if it goes BANG! while i'm stood next to it, always seems to me a bit like a plumber checking for gas leaks with a match, BANG! "found one":confused:

Cheers Jon

.... you can do it with old clean oil or water - hydraulic test and NO BANG .... safety and the ONLY way to do it ... DO NOT USE ANY GAS FOR PRESSURE TEST OF VESSEL, EVER, PLEASE here I mean about strength test, for leak test it is ok;)

Best regards, Josip :)

monkey spanners
12-08-2008, 09:24 PM
That Araldite is wonderful stuff....

Peter_1
12-08-2008, 09:45 PM
Hi, monkey spanners :).... you can do it with old clean oil or water - hydraulic test and NO BANG .... safety and the ONLY way to do it ... DO NOT USE ANY GAS FOR PRESSURE TEST OF VESSEL, EVER, PLEASE here I mean about strength test, for leak test it is ok;)

Best regards, Josip :)

Was going to make the same comment Josip. If you pressurize with gas and it cracks, then you will have a serious explosion.
Not with a liquid because it doesn't expand.

knighty
15-08-2008, 02:12 AM
a bit like a plumber checking for gas leaks with a match, BANG! "found one":confused:Cheers Jon


there's another way to do it ?








(seriously tho... I do that all the time.....)