gas question

**l921428x** · 10-01-2014, 10:59 AM

the other day I was out and heard someone say the gas had gone flat.
he was talking about acetylene. now I was a pipefitter for more than 20 years
and I have never heard that term. to me it was weird.
any insight?

**N/A** · 10-01-2014, 11:22 AM

When you screw up, blame the equipment.

**Krupski** · 10-01-2014, 12:12 PM

Originally Posted by l921428x

the other day I was out and heard someone say the gas had gone flat.
he was talking about acetylene. now I was a pipefitter for more than 20 years
and I have never heard that term. to me it was weird.
any insight?

Don't see how acetylene can "go flat".

Acetylene C-H≡H-C has a triple bond between the carbons, it releases a LOT of energy when it's burned and that triple bond breaks (making acetylene burn hotter than other hydrocarbon fuels).

This triple bond also makes acetylene dangerous. If compressed beyond 15 PSIG, it can spontaneously decompose (break that triple bond) and detonate with a very powerful blast.

To make it safe, acetylene for welding is stored in cylinders filled with acetone or other solvent (and sometimes with chunks of balsa wood in the tank to minimize sloshing) and the acetylene is dissolved in the solvent (same as carbon dioxide is dissolved in water to make carbonated soda).

To release the acetylene, the tank valve is opened and acetylene bubbles out of solution and out the tank (just like CO2 comes out of a new soda bottle when opened).

It's possible the person you overheard was talking about MAPP gas which used to be awesome and now sucks.

MAPP (Methyl Acetylene ProPadiene) was basically acetylene mixed with other hydrocarbons (diluted really) in order to make it safe to store as a high pressure liquefied gas.

Unfortunately, real MAPP is no longer produced (they stopped making it in 2008) and now they sell stuff called "MAP Pro" which is a shit mixture of propane LPG and propylene.

It burns hotter than plain propane LPG, but it's nowhere near as good as MAPP was.

Maybe that's what the guy was talking about? MAPP?

**Helen Keller** · 10-01-2014, 01:48 PM

Mapp/Pro sucks ass, IIRC there was only one place in the country making the original MAPP
i found a place locally that still had some in stock and it was 2X what it was originally.

other than sweating solder off of barrel sleeves/sights and older copper pipe work , shits worthless.
not even hot enough to bring small parts into hardening temps.

Krupski if you want to be a millionaire, figure out the magic on how to chemically create helium VS the bombardment process.

**Krupski** · 10-01-2014, 02:56 PM

Originally Posted by Helen Keller

Mapp/Pro sucks ass, IIRC there was only one place in the country making the original MAPP
i found a place locally that still had some in stock and it was 2X what it was originally.

other than sweating solder off of barrel sleeves/sights and older copper pipe work , shits worthless.
not even hot enough to bring small parts into hardening temps.

Krupski if you want to be a millionaire, figure out the magic on how to chemically create helium VS the bombardment process.

Easy: Fill a 55 gallon drum with hydrogen, then have Rosie O'Donnell sit on it. The immense pressure exerted on the gas will heat it to fusion temperatures and not only create helium, but also a lot of energy to help with that oil dependence problem we have........