Oxy/AC tanks, hauling safely, and storage

[Glenn]

The sign on the front glass double door to the welding supply dealer says "we will not load any gas tanks into a closed vehicle." This would mean that I can not use a utility van, wife's car, etc to transport the gas cylinders.

If I use "the truck", standing a 4 foot tall cylinder up next to the cab just invites it to tip over on the first corner. Lay it down in the bed of the truck and it rolls from side to side.

This brings up a couple of questions.

(1) What is a SAFE way to transport cylinders?
Is it better to transport the cylinder valve to the front or valve to the back? How do you tie the cylinders down to keep them from rolling around?

(2) If a cylinder is on it's side, how long do you have to wait before you can use the cylinder after you stand it upright?

(3) While we are on a roll, what is a safe way to store the cylinders upright while they are in the shop?

YES I do put a cap on over the valve when ever the tank is not in use, including during transport.

[Dodge]

I stand cylinders with caps up in my truck and use a nylon ratchet type cargo strap to secure. I put cylinder(s) in the front passenger side corner (so I can keep my eye on it/them) and hook the strap to the tie down eye, then wrap around tanks, then back to the eye. Ratchet the strap tight and they stay put. I don't engage in any drag racing or off-road excursions while transporting, of course.
I have laid them down before and wedged something under them (wooden wedge, angle iron, etc) to keep them from rolling in a pinch. A "cradle" could be easily made from many different materials to allow bottles to ride without rolling.
NOTE: Acetylene bottles shouldn't be laid down, but if you must, a rule of thumb is to stand bottle back up for the same period of time (or longer) as the bottle was laying down before use so the contents can settle.

[HWooldridge]

I tie mine upright to the headache rack in the truck bed. I don't like them rolling or lying down so I take special pains to keep them more or less immobile.

Our welding store WILL NOT put them in a closed vehicle. My wife tried to do me a favor and swap out my O2 in her Suburban one day and they told her "No", which was perfectly fine with me.

[Ice Czar]

(1) What is a SAFE way to transport cylinders?
Is it better to transport the cylinder valve to the front or valve to the back? How do you tie the cylinders down to keep them from rolling around?

upright only and chained

(2) If a cylinder is on it's side, how long do you have to wait before you can use the cylinder after you stand it upright?

dont put the cylinder on its side, you do not want the acetylene and acetone to separate, unless there is someone you really dont like

(3) While we are on a roll, what is a safe way to store the cylinders upright while they are in the shop?

to a wall, post or cart with a safety chain preventing it (them) from tipping over

http://www.depweb.state.pa.us/deepmi...yacetylene.ppt

[R Funk]

I usually lay my cylinders down as I feel it is safer than hauling them upright unless you have a very good way of securing them upright.

There is nothing wrong with laying O2 cylinders down and I go through O2 much faster than fuel.

Dodge is exaclty correct on the Accetylene. They must be stored upright for period of time equal to amount of time they were layed on their side and longer is better.

I have spare cylinders so I am in no time pressure to use the cylinder I just got so leaving them upright at least overnite before usage is not an issue.

By the way per DOT rules you can haul 1000 lbs of compressed gas cylinders before you need a "placard" on your vehicle, so for most of us that will not be an issue. Of course toxic or corrosive gases have smaller limit. Your insurance company will be very unhappy with you if you need a placard, especially if you have an accident.

[Ice Czar]

Acetylene

Due to the carbon-to-carbon triple bond, acetylene gas is fundamentally unstable, and will decompose in an exothermic reaction if compressed to any great extent. Acetylene can explode with extreme violence if the pressure of the gas exceeds about 100 kPa (≈14.5 psi) as a gas or when in liquid or solid form, so it is shipped and stored dissolved in acetone or dimethylformamide (DMF), contained in a metal cylinder with porous filling (Agamassan), which renders it safe to transport and use.

History - Acetylene dissolved in acetone

In 1896 the French scientists Claude and Hess discovered a way to store and transport acetylene without the risk of explosion. This method is based on the fact that acetone can dissolve many times its own volume of acetylene. The French call acetylene dissolved in acetone acétylène-dissous. At a pressure of 10 atmosphere one liter of acetone dissolves approximately 250 liters of acetylene.

But the near-accidents continued. Claude and Hess filled the containers with a porous compound which formed a system of small capillaries. The compound was drenched in acetone and then filled with acetylene. Since an explosion cannot spread in a tube with a diameter of a fraction of a millimeter, the inventors considered the problem solved. But the compound failed to meet expectations. Over time large holes could appear and explosions could occur.

Pennsylvania Dept of Environmental Protection , Deep Mine Safety, Oxy-Acetylene Safety Awareness ppt

it is an unstable gas, will violently decompose when in a pure state above 15 psi

Auto-ignition temperature is 763-824F, this means if Acetylene reaches 30 psi in a free state, it can explode by itself without a spark or flame being present

the firebrick also helps by minimizing the free volume of the cylinder, cooling and controlling any thermal decomosition before it gets out of control (each decomposition of acetylene gives off heat)

porous filler 8-10%, Acetone 42% Acetylene 36%
Must always be stored upright, this prevents the acetone and acetylene from seperating

Acetylene, the Principles of Its Generation and Use by Butterfield and Leeds - Project Gutenberg

[Tyler Murch]

I heard that an acetylene cylinder laid on its side can blow the top off. Is that true?

[Ice Czar]

it would take several unfortunate variables to coincide for that to occur


http://www.hse.gov.uk/pubns/indg327.pdf
this pdf starts with the tale of a cylinder spliting in two and sprouting wings (and a million pounds of damage to a UK factory)

An acetylene cylinder has a different design from most other gas cylinders. The porous mass is a cellular structure which completely fills the cylinder. The acetylene gas in the cylinder is dissolved in acetone which is absorbed by the porous mass. Decomposition of the acetylene is usually triggered by heat. For example if the cylinder is:

involved in a fire
scorched by flames from a blowtorch
involved in a flashback

the porous mass is designed to slow down or stifle any decomposition of the gas. From start of decomposition to the cylinder exploding should take several hours. This will usually (but not always) provide time for emergency action.

Decomposition can be triggered more easily and can proceed more rapidly if:

the porous mass has been damaged by repeated flashbacks or by mishandling or dropping the cylinder

the cylinder vavle is leaking gas (an open or leaking valve increases the rate of decomposition within the cylinder)

the acetylene in the hoses is above the pressure recommended by the supplier.

--------------

Handling acetylene cylinders with care

do not drop them
do not roll them across the floor
keep them in an upright position

in and of itself, horizontal storage will not cause an explosion,
but you also cant see inside the cylinder to ascertain the integrity of the filler
and it is a vital component to the stability of the storage
any decomposition in a damaged cylinder can progress to thermal runaway

[Ten Hammers]

I haul bottles laying down in the back of the truck. I have angle iron to secure the rolling issues. 19 mi for the torch set ( acetelyne o2 ) and I guess one mile for the hundred lb propane for forge. Acetelyne is set upright and not used until next day ( but valve still cracked before hooking up regulator as in all bottles ). As Scott said, good driving habits. I have no real way to build a secure upright setup to haul bottles in the Nissan ( with toolbox in back ). My welding supplier has no issues with hauling bottles laying down. No reputable supplier ( welding or LP ) will let you haul bottles in an enclosed space. Good reasons. I might also add that if you do not have training to handle and or haul bottles, get the training.

[Paragon]

You can lay acetylene down bet even for a short 20-30 minute short trip, I would let it sit for at least an hour before use. The place I go has one that is cut in half. The inside is totally filled with a porus material.

I made a carrier out of wood that I put behind the passenger set of the car. I set the cylinders in that and tie it up and wedge it in with the front seat. It is not moving anywhere and it is better than having them in the trunk. I don't have a truck so I do the best I can.

The thing you have to remember with acetylene is that it is heavier than air so can settle in low areas. I usually drive with the window open and drive straight home.