The tanks in question are a 50 pound argon/helium mix for welding and a 25 pound CO2 tank. Are there any laws regarding the transport of these tanks? Im assuming that I can tie them down in the bed. The Ar/He mix is 50% full and the Co2 is about 75% full.

 

No special laws that I know of, just make sure they can't roll and that the valves are protected. The CO2 isn't a hazzard but I don't remember on the Argon/Helium mix if their ubber high pressure gas or not. If so they'll have a screw on cap to protect the valve.

Some stores sell wedges with a curve in them specifically for hauling gas tanks. They're worth spending a couple $$ on to keep everything in place.

 

I've been told by professional welders (I'm just an amateur) that cylinders of welding gases (empty, partial or full) should always be transported upright, chained in place and valve covers installed.

 

It would be wise to have an MSDS for all compressed gases.
Better to have and not need, than to need and not have.

You can obtain them at Air Products web site.

 

The short answer is transporting those cylinder's is not regulated. The slightly longer answer is, if welding is part of your job, The Code of Federal Regulations Part 49 (CFR49) which covers the transportation of hazardous materials would consider your 50lb cylinder of Helium/Argon, and 25lb cylinder of Carbon Dioxide to be a "Material of Trade". And they are basically not regulated. You still need to have the proper markings on the He/Ar and CO2 cylinder's though. The green diamond shaped labels that contain a picture of a cylinder at the top, the words "NON-FLAMMABLE GAS" in the middle and a #2 at the bottom. The cylinders also need to have the cylinder owner's name on them. If you were transporting cylinder's that were more than 220 pounds a piece it would be a whole other ball game. In which case, since He, Ar, and CO2 are all listed hazardous materials by the DOT, they would be regulated.

 

always carry them up right valves covered and chained in place.

 

I see people mention transporting upright and chained all the time but if you're in a pickup those suckers get top heavy and can be next to impossible to keep up and stable unless you have a rack to tie them to.

I'm not sure about the large CO2 tanks but the shorter tanks don't have a cap on them. If I remember correctly CO2 is a liquid in the tank and evaporates when depressurized giving you the gas. Because of this it is not explosive if ruptured like an oxygen tank.

 

Argon/CO2 mix cylinders, like used in MIG welding ARE most definately under pressure. Two ex-employees managed to launch one through the wall at my old job. Luckily it shot out into a truck dock area, hitting a concrete barricade and nothing else.

 

There's nothing wrong with laying the cylinders down as long as they are secure. The only cylinders I aware of that should be transported and used in a vertical position are those containing acetylene.

 

OKST1 is right about the acetylene cylinders. When you lay them down, the acetone inside flows just like any liquid, and if you operate them this way it will be sucked into your acetylene hose. When I've had to lay mine down, I always made sure the acetylene was the first one I stood back up and the last line hooked up, just to give everything more time to settle down. This doesn't mean the cylinder has a lot of acetone in it, but there's enough there to mess things up if you use the cylinders when they're horizontal.