Calculate volumes for vertical, horizontal and spherical vessels with all head types. Correct equations for each head. Live vessel drawing updates as you type. Full partial fill strapping table included.
UPDATES LIVE WITH INPUTS
Volume at each liquid level — for level transmitter calibration, inventory management and alarm setpoint engineering.
| Level % | Level (mm) | Volume (m³) | Volume (Litres) | Fluid Mass (kg) |
|---|
A vessel volume calculator determines the total internal volume of a pressure vessel, storage tank or process vessel based on its geometry. For process engineers and mechanical engineers, accurate vessel volume is required for level transmitter calibration, fluid inventory calculations, hydrotest planning, relief valve sizing and alarm setpoint engineering.
This tool handles vertical vessels, horizontal vessels and spherical vessels, with all standard dish head types — 2:1 ellipsoidal, hemispherical, torispherical (Klopper), conical and flat. It also generates a partial fill strapping table showing volume at every 5% level increment, which is essential for level transmitter calibration and custody transfer applications.
The choice of dish head type significantly affects vessel volume, especially for smaller vessels with a large head-to-shell ratio. Each head type has a specific volume formula based on its geometry.
The partial fill strapping table gives volume at each liquid level, used to calibrate differential pressure transmitters, guided wave radar and displacer level instruments.
Calculate the exact water volume required to fill a vessel to 100% for hydrostatic pressure testing per ASME VIII or PED requirements. Plan water supply and disposal logistics.
Convert between liquid level in millimetres and volume in litres to calculate high level alarm (HH/H) and low level alarm (LL/L) setpoints for the vessel control philosophy.
Determine the vapour space volume above the operating liquid level — an input parameter for fire case and blocked outlet relief valve sizing calculations per API 520/521.
Enter the tangent-to-tangent (T-T) length — the length of the cylindrical shell section only, measured from the tangent lines where the heads begin to curve. Do not include the head depths in this measurement.
The strapping table uses the theoretical geometric equations for each head type. For custody transfer applications, always use the vendor-certified strapping table from the vessel manufacturer, which accounts for actual head geometry, nozzle penetrations and shell thickness.
Yes — select Horizontal Vessel and choose your head type. The tool correctly calculates total vessel volume for horizontal orientation. The strapping table for horizontal vessels uses a simplified linear approximation; for precise horizontal partial-fill calculations, a dedicated horizontal vessel strapping tool is recommended.
Head volume equations are based on standard fabrication geometry per ASME BPVC Section VIII Division 1 — Rules for Construction of Pressure Vessels, and EN 13445 — Unfired Pressure Vessels. Torispherical head volume uses the Klopper approximation widely referenced in process engineering literature. Results are for preliminary engineering estimation — always verify with the vessel manufacturer's certified data sheet and drawing.