Gas Cylinder Duration Calculator

About the Gas Cylinder Duration Calculator

Estimates how long a compressed gas cylinder will last from its content volume (at the regulated flow) and the consumption flow rate.

How to use this calculator

1. Enter the cylinder content, usually in units like liters of gas or a filled amount converted to the same unit as the flow rate.
2. Enter the flow rate, such as liters per hour, making sure the units match the cylinder content.
3. Use the calculator to divide the cylinder content by the flow rate.
4. Read the result as the number of hours the cylinder should last at that constant rate.

The formula explained

The formula computes the number of hours the gas supply will last. It works by dividing the total cylinder content by the amount used each hour, so the units cancel correctly to give time.

• hours = the estimated time the cylinder will last, in hours
• \(cylinder\ content\) = the total amount of gas available in the cylinder
• \(flow\ rate\) = how much gas is used each hour

Step by step method

1. Write the known values for cylinder content and flow rate with matching units.
2. Divide the cylinder content by the flow rate, using \(hours = \\frac{cylinder\\ content}{flow\\ rate}\).
3. Check that the answer is in hours, and convert to minutes if needed by multiplying the decimal part of an hour by \(60\).

Worked example

Problem. A cylinder contains \(180\) liters of gas and the flow rate is \(12\) liters per hour. How long will it last?

1. Use the formula \(hours = \\frac{cylinder\\ content}{flow\\ rate}\).
2. Substitute the values, \(hours = \\frac{180}{12}\).
3. Compute the result, \(hours = 15\).

Tips and common mistakes

• Make sure the units match before dividing, for example liters and liters per hour, or cubic feet and cubic feet per hour.
• This gives an estimate for a constant flow rate, so changing the setting will change the result.

Frequently asked questions