The 'tricks of the trade' column...

[stew]

Originally Posted by A. Berk

Most commercial operations use Dr Broco's all-purpose releasing agent these days. Broco, being 'oxy-thermic' will go through just about anything you need to cut, though mostly you're going to be cutting steel.

guess what im doing tomorrow for the first time in my life...
nice timing..

[Madfish]

Good luck Stew!

Di

[A. Berk]

OK, it's time for the safety stuff now..

The greatest hazard to a diver using u/water burning gear is; EXPLOSION! Sadly, the number of fatalities caused through burning runs in the 100's.

For an explosion to occure three elements are needed; Oxygen, Heat and Fuel - the 'Fire Triangle'. Two of these the diver holds in his hand, Oxygen and Heat - both supplied by the cutting torch. The third - Fuel, is generated by the oxy-thermic process itself which creates a number of gases such as Hydrogen, Oxygen and Methane. For an explosion to happen it takes nothing more than a pocket of these gases to be hit by a stray spark from the cutting torch. Its worth baring in mind that 100 litres of hydrogen has the explosive equivalent of 0.5 pounds of TNT. Before starting a cut be sure that pockets of gas cannot collect either within the material you are cutting or in overhead areas. When cutting a sealed container such as a tank or pipe make sure you have good vent holes to allow gases to escape. It may be necessary to make vent holes by 'cold' methods like drilling or grinding (use a hacksaw/hammer and chisle if you have to) - extra hassle I know but better the hassle than having your helmet blown off your head. Make sure that heavy marine growth is removed from the cut site - although Broco will zapp through barnacles etc, when marine organisms burn they too give off Methane - besides, its easier to get a clean cut without all that crap in the way. If you're cutting a bulkhead make sure you know what's on the other side and that no gas can build up there either.

Be sure that the polarity of the rig is correct - put the gun (with rod fitted) and the 'earth' clamp in a bucket of water. Hold the end of the rod about 50mm below the earth clamp and with power 'on' you should get a stream of bubbles rising from the rod tip. If not - reverse the polarity and try again. Ensure that DC current is used - NEVER use AC for u/water burning or welding.

Always wear a visor - you only get one set of eyes and it makes for better cutting.

Always wear heavy rubber gloves - you may still get the odd belt though!

Don't get between the gun and earth clamp when burning.

Always make the gun 'Cold' when changing rods, changing position or when not actually burning.

If you're burning or cold cutting a vent hole into a sealed space beware that it may have suction behind it - a 20mm hole with 3 bar differential can suck the flesh off your hand.

Tape over sleeves of wet-suits or coveralls to prevent the migration of gas into your suit - this has caused fatalities.

Remember - If in doubt, there is no doubt - cut it cold!

Safe diving,

Berko

PS; A BIG thanks to the Mods for making this thread sticky... I kicked it off but it's open to all and I'm sure there are old hands out there who have some gems of info to help the new guys along - lets have 'em!

[BigHairyAl]

Originally Posted by A.Berk

OK, it's time for the safety stuff now..

Always wear heavy rubber gloves - you may still get the odd belt though!

Indeed - it feels like Hatton did after that right hand from Mayweather at the weekend

You often get a warning sign when welding - a warm tingling feeling in the fingers, giving you plenty of time to rethink your positioning. Not so with the broco, it kicks like a mule before you know anything about it.

[Iain Hamilton]

Originally Posted by BigHairyAl

Indeed - it feels like Hatton did after that right hand from Mayweather at the weekend

You often get a warning sign when welding - a warm tingling feeling in the fingers, giving you plenty of time to rethink your positioning. Not so with the broco, it kicks like a mule before you know anything about it.

yeah strange one that, when i practiced wet welding at school i was happy with my normal latex palmed work gloves, once it was hot it stayed hot, changed rods out hot etc, used to get the tingling in the fingers and especialy in any little cuts and nicks in my fingers, but the broco was awfull, top side couldnt "make it cold" quick enough for my liking.

I heartily recomend the full rubber gloves.

[bruno007]

Hi all this info is great, much appreciated.....

Has anyone else out there got any more tricks of the trade to hand to help us out????

[A. Berk]

Originally Posted by bruno007

Hi all this info is great, much appreciated.....

Has anyone else out there got any more tricks of the trade to hand to help us out????

When walking down Copacabana at night, jam your wallet down by your nuts. Troops of 'drop-dead gorgeous' honies roam Rio and 'dip' unsuspecting Gallago's (that's us) by distracting them with subtle tricks like sticking the 'lip-lock' on yer or poking their tongues in yer ears - allegedly

Anyhow, a serious one to follow below in the next posting........

kroBe

[A. Berk]

Pneumo's are the device we use to register a divers depth. They are nothing more than an extended 'Bourdon Tube' (remember those from physics class?) and are extremely accurate when used correctly. Strangely, using them correctly seems to be a problem for quite a few divers and also supervisors who don't understand the principal.

The divers umbilical bundle is made up from various hoses and cables for a number of functions; Air/Gas hose obviously, hot-water hose, gas reclaim hose (sat divers), comms cable, light and camera cables and........... the 'Pneumo' hose. This is simply a small bore open-ended hose through which air/gas is blown from the control panel, once bubbles are seen to emitt from the end the diver reports, "Got bubbles!" and the supply valve is shut. When the bubble flow stops the diver reports, "Bubbles stopped!". The resultant back-pressure created at the end of the hose is read by the dive supervisor on a gauge in either metric or imperial - we now know you're at 123.5 metres - easy peesy!

Now, in an ideal world when dressing a diver, the 'tenders' should ensure that the pneumo hose is coiled on the divers harness at chest level - that way your chest level is monitored and because of the coiled hose the Bourdon Tube effect works fine. However, on occassion you as a diver may be asked to give a 'pneumo' of an item such as the top of a pipeline or a certain position on a platform leg perhaps. To do this may require you to un-coil the pneumo hose from the front of your harness to give you enough spare hose to hold the end where you want to take the depth reading. Now this is where some folk f*ck-^p.

For the reading to register accurately at the hose-end, that hose-end has to be pointing downward. If it isn't the gauge on the surface will register the deepest point at which your pneumo hose takes a bend - which could be 2 - 3 metres below you - no good. In the last couple of years I have seen so many divers (some experienced ones too) attempt to give a pneumo reading while holding the hose 'end-up' and often this hasn't been noticed by the supervisor. Remember that although in this instance we are talking about accurately recording the depth of an item of work (and that accuracy is important to the project) the pneumo also tells the supervisor your depth - which to you as the diver is more important than anything else right? So, point the end down and recoil the hose back to your chest when done - it doesn't have to be pretty, just make sure there is some kind of loop there.

The 'pneumofathometer' to give its full name is also known as a 'Kluge' on the other side of the pond - not the one with ducks on, the big one! In an out-of-air/gas emergency the pneumo hose can sometimes be used as a source of gas by jamming the end up through your neck-dam and into your helmet - the supervisor should react by automatically giving 'bubbles' to your hose but in such an instance I wouldn't be offended if the diver yelled "PNEUMO!!!!!" at me.

Berko

[Iain Hamilton]

heres a pic of the pneumo.

[spongebobb]

matching hose and suit !!!
ian thats twee ,