Horizontal tank (bullet tank) volume calculator

Calculating the volume of an inclined tank with hemispherical heads (caps) is a complex problem because the liquid level is not uniform. This tool uses a numerical integration method to digitally "slice" the tank into thousands of small sections and sum their individual volumes. This allows for high accuracy even when the tank has an angle of inclination. However, it is not based on standards such as ISO 12917-1, as it does not account for deductions due to welds, deformations, pressure changes, or temperature variations. The volume obtained is the actual volume, not corrected to reference conditions.

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Why is it important to know the volume?
Knowing the exact volume of a tank is not just a matter of measurement; it is a fundamental pillar for operational management, safety, and profitability. Accurate calculation is vital for several key reasons:

Inventory and Logistics Management: It allows for precise stock control. Knowing how much product (fuel, raw materials, finished goods) remains in the tank is essential for planning purchases, production, and distribution logistics.

Safety and Regulatory Compliance: Avoiding overfilling is critical. An inaccurate calculation can lead to spills, resulting in safety risks, costly environmental damage, and potential legal penalties. Knowing the available volume prevents these accidents.

Custody Transfer and Trade: When the tank's contents are bought or sold (such as at fuel terminals or in the food industry), the exact volume is the basis of the commercial transaction. Accurate calculation ensures fair trade and is often a requirement for tax certification.

The calculation is based on the disk method, an integral calculus technique. Instead of using a single geometric formula, the script treats the tank as the sum of thousands of small disks or "slices."

 

Decomposition: First, the tank is digitally divided into its three main components: the lower head (lid), the cylindrical body, and the upper head (lid).

1. Slicing: Each of these three sections is divided into thousands of very thin vertical slices (specifically for this calculation, we use 2000 slices per section).

2. Calculation per Slice: For each individual slice, the calculator performs the following:

3. It determines the exact radius of that slice (in the heads, this radius changes; in the cylinder, it is constant).

4. It calculates the precise height of the liquid within that specific slice, compensating for the tank's tilt angle (θ).

5. Using a function, it calculates the exact area that the liquid occupies in that slice.

6. Total Sum: Finally, the area of ​​each slice is multiplied by its thickness to obtain its volume. The sum of the volumes of these thousands of slices (from the three sections) results in the precise total volume shown.

 

If you need to convert that volume to other units, you can go to our volume unit converter by clicking here.