Gas Tanks - Oxygen and Propane
Usually rented at your local welding shop. Tank size can vary between 20 cubic feet of oxygen to about 300 cubic feet of oxygen. The larger the tank, the cheaper the price is per cubic foot. Prices can vary a lot depending on location and store and are usually negotiable. Shop around. I have seen prices for large tanks under $10 to over $40. We pay $25. Each time you refill, you will pay this fee (tanks are actually exchanged, empty for full, ). There is also a monthly rental fee for each tank, usually between $3 and $5 and oftentimes requiring a deposit, around $100. You can bring the tank to the welding shop for exchange or have the welding shop deliver it to you, for a fee of course. Don't forget to find out what this fee is when you are like residential neighborhoods. Ask them. Also consider how heavy the tank will be if you have to move it yourself or up stairs.
How about buying your tank instead of paying a monthly rental fee? Sure! The "break even" point may be 4 years. Tanks are running around $300 to purchase. But no monthly rental fee. Run the numbers. How long does the tank last? It depends on the torch and is the torch setting high or low. Typically a Minor Burner Torch set at a medium setting will use about 15 cubic feet of oxygen per hour or approx $1 per hour. We have been talking about a compressed gas tank. There is also another type of oxygen available, liquid Oxygen. When Oxygen is couled it turns from a gas into a liquid. You can use a tank of liquid Oxygen. It will last a long time and would cost much less to run your torch. Cost of a 160 liter tank is about $100 to $200. Also a $1.50 to $2 per DAY rental fee. We pay $45 per month. Once again, shop around.
liquid compared to Compressed Tanks of Oxygen
|Advantages of liquid||Disadvantages of liquid|
|2 to 3 times less expensive than compressed||Large heavy tank needs to be delivered. Neighbors may get upset seeing a "scary" looking tank being delivered to you.|
|May not be available in all areas|
|Some suppliers do not want to sell and deliver to residences or homes, only businesses.|
|Within hours or a day after the tank not being used, the oxygen leaks, bleeds off, and continues to bleed until you begin to use it again. It is designed to bleed off. Remember the liquid is warming and turning to a gas and it needs to go somewhere. You must use the tank often, almost daily to take advantage of the cheaper price.|
Simply use a standard 5 gallon (or larger) Barbecue Propane Tank that can be purchased at your local hardware store. Costco has a good price but sells only in the BBQ season.
|14.1 Ounce Disposable Cylinder||19,000 BTU's|
|16.4 Ounce Disposable Cylinder||22,000 BTU's|
|7 Pound Refillable Cylinder||150,000 BTU's|
The BTU's of a torch can vary a lot a lot depending if the flame setting is low or high.
There are 96,000 BTU's in one gallon of Propane.
Another option is to use Propylene Fuel which is a little hotter than propane. Propylene Fuel is also called Brazing Fuel or a common brand name is MAPP Gas. You can purchase Propylene two ways:
- Disposable Cylinders - Around $9. You can usually find them at your local hardware store.
- Refillable Cylinders - Sometimes difficult to find. Check with your local welding shops. Air Gas, a large supplier of, welding supplies, sells Propylene in 3 sizes:
|Size of Tank||Who Owns Tank||Daily Rental Fee||Refill Charge|
|7-1/2 LB||Tank ownership||none||$22.50|
|30 LB||Rental||27 cents||$32.76|
|60 LB||Rental||27 cents||$109.50|
Most torches work with natural Gas. Cost of the gas is about the same.
|Advantages of Natural||Disadvantages of Natural|
|More convenient, you do not have to refill tanks.||Propane has a hotter flame than natural gas. This is the big reason not to use natural gas unless you have to.|
|You never run out of gas.||May require a plumber to make the gas outlet near your work area, where the propane setup is easily moveable.|
|You don't need a Propane Regulator||Nature Gas pressure is not adjustable. You are stuck with the barely minimum pressure available.|