Online Pipe Weight Calculator
Pipe Weight Calculator
MLTI Private Limited manufactures stainless steel pipe from 1/8 inch to 10 inch NB. This pipe weight calculator returns the theoretical weight of a round pipe from three inputs: outside diameter, wall thickness and length. It is a very simple and easy-to-use weight calculator of pipes. Selecting the material applies the density, and results are reported in kilograms per metre and pounds per foot. The pipe weight formula, the constant for each material family and a worked calculation are given below.
How to Use the Pipe Weight Calculator
Follow the four steps given below for the calculation of pipe weight. The same steps apply to seamless and welded (ERW) pipe, because calculating weight of pipe depends only on geometry and density.
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1
Enter the outside diameter: Use the true OD in millimetres or inches, not the nominal bore: a 2 inch NB pipe measures 60.3 mm.
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2
Enter the wall thickness: Where only the schedule is known, read the wall from ASME B36.19M or our SS pipe schedule table.
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3
Enter the length: One metre is the default; entering the full batch length returns the consignment weight.
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4
Read the output: The tool reports kilograms per metre, pipe weight per foot and total weight, for freight and costing.
Pipe Weight Formula
Weight calculation for pipe reduces to one geometric relationship: the metal occupies a ring of constant thickness, and that ring's volume multiplied by density gives mass. Subtracting wall thickness from outside diameter gives the ring's mean diameter, which is why (OD - WT) appears in every form of the formula.
Weight (kg/m) = π × (OD − WT) × WT × Density ÷ 1,000,000
OD and WT are in millimetres, density in kg/m³. Fixing the density for a material family collapses the leading term into one constant:
Weight (kg/m) = (OD − WT) × WT × Constant
- Austenitic stainless (304, 304L, 316, 316L, 321, 347)0.02513
- Duplex S31803 and S322050.02450
- Hastelloy C2760.02793
Weight (lb/ft) = (OD − WT) × WT × 10.90
Both dimensions are in inches. The constant 10.90 applies to austenitic stainless at 0.2891 lb/in³ and moves with density.
Worked example, 4 inch SCH 40S pipe in 316L. Outside diameter is 114.3 mm (4.500 in) and wall 6.02 mm (0.237 in). Subtraction gives 108.28, multiplied by 6.02 gives 651.85, and by 0.02513 gives 16.38 kg per metre. A 6 metre length weighs 98.3 kg, or 11.01 lb/ft.
Frequently Asked Questions about Pipe Weight Calculator
Here’s how to do the calculation of pipe weight: Multiply (OD - WT) by WT and by the material's density constant. For austenitic stainless in millimetres, the constant is 0.02513, returning kilograms per metre.
Schedule 40 wall thickness varies with bore: 2.77 mm at 1/2 inch NB, 3.91 mm at 2 inch, 6.02 mm at 4 inch and 9.27 mm at 10 inch.
Across the 1/8 inch to 10 inch range the two walls are identical. They separate at 12 inch and above, where SCH 40S is lighter.
Theoretical weight assumes nominal dimensions, while ASTM A312 (through A999/A999M) permits the wall to run up to 12.5% under nominal, with no plus limit on wall thickness, and allows seamless pipe mass to vary +10% and −3.5%.
Our SS Pipe weight calculator uses a 7,700 kg/m³ density for austenitic Stainless Steel Pipes.