Lpg Tank Relief Valve Capacity

Overview

Engineering reference data for Lpg Tank Relief Valve Capacity in gases and compressed air.

Key Formulas

Ideal Gas Law

$PV = nRT$

Pressure × Volume = moles × gas constant × temperature.

Boyle's Law

$P_1 V_1 = P_2 V_2$

At constant temperature.

Charles's Law

$\frac{V_1}{T_1} = \frac{V_2}{T_2}$

At constant pressure.

Variables

Capacity Diagrams & Unit Conversion

The required relief valve capacity for LPG tanks and vaporizers is determined by the surface area of the equipment. The relationships are visualized in the diagrams referenced in the Overview.

Imperial & Metric Flow Relationships

The capacity can be expressed by the following relationships, which are the basis for the referenced charts:

For above-ground and below-ground tanks: $Q_{air} = f(A)$

Where:

• $Q_{air}$ is the required air flow rate for relief valve capacity.
• $A$ is the surface area of the vessel or vaporizer.
• The function $f$ is defined by the specific diagram curves.

Unit Conversions for the Charts:

• Imperial: Area in square feet ($ft^2$), Flow Rate in cubic feet per minute of air ($cfm_{air}$).
• Metric: Area in square meters ($m^2$), Flow Rate in liters per second of air ($l/s_{air}$).

Example Conversion: $1 \, cfm \approx 0.472 \, l/s$

References

• Original Source