# Calculate Pipe Weight

## Weight calculating formula for steel pipes

### Weight of Empty Pipe

Weight of empty pipe per unit length can be calculated as

w_{p}=ρ_{m}A_{m}

=ρ_{m}π(d- d_{o}^{2 }_{i}^{2}) / 4

(4)=(/ 4)πρ_{m}(d- d_{o}^{2 }_{i}^{2})

where

w_{p}=weightof empty pipe per unit length (kg/m, lb/in)

= density of pipe material (kg/mρ_{m}^{3}, lb/in^{3})

A_{m}= cross-sectional wall area of pipe (m^{2}, in^{2})

d_{o}= outside diameter (m, in)

d_{i}=dinside diameter (m, in)_{o}- 2 t =

t = wall thickness (m, in)

### Weight of Liquid in Pipe

Weight of liquid in pipes per unit length can be calculated as

w_{l}=ρ_{l}A_{i}

=ρ_{l}π (d_{i}/ 2)^{2}

= (π/ 4)ρ_{l}(5)d_{i}^{2}

where

w_{l}= weight of liquid in pipe per unit length of pipe (kg, lb)

A_{i}= cross-sectional inside area of pipe (m^{2}, in^{2})

= density of liquid (kg/mρ_{l}^{3}, lb/in^{3})

### Weight of Pipe with Liquid

Weight of pipe with liquid can be calculated as

*w = w _{p} + w_{i} *

* = ρ _{m} A_{m} + ρ_{l} A_{i} *

* = (ρ _{m} π (d_{o}^{2 } - d_{i}^{2}) / 4) + (ρ_{l} π d_{i}^{2} / 4)*

* = (π / 4) [ρ _{m} (d_{o}^{2 } - d_{i}^{2}) + ρ_{l} d_{i}^{2}] (6) *

#### Weight of Pipe Calculator

This calculator can be used to calculate the weight of a pipe with - or without - liquid. The calculator is generic and can be used for both SI and Imperial units as long as the use of units are consistent.

*d _{o} - outside diameter (m, in)*

*d _{i} - inside diameter (m, in)*

* ρ _{m} - density of piping material (kg/m^{3}, lb/in^{3})*

* ρ _{l} - density of liquid (kg/m^{3,} lb/in^{3}) (zero for empty pipe)*

*1 m = 10*^{3}mm*1 m*^{2}= 10^{6}mm^{2}*1 in = 1/12 ft**1 in*^{2}= 1/144 ft^{2}*1 lb/in*^{3}= 1728 lb/ft^{2}

### Example - Weight of 4" Schedule 40 Steel Pipe

The outside diameter of 4" Schedule 40 Steel Pipe is *4.500 inches.* The wall thickness is *0.237 inches* and the inside diameter is *4.026 in*. The density of steel is *490 lb/ft ^{3} (0.28 lb/in^{3})*. The weight per inch length of empty pipe can be calculated as

m=(0.28(/ 4)π) (lb/in^{3}(4.500 in)-^{2}(4.026 in))^{2}

= 0.89 lb/in

= 10.7 lb/ft

### Example - Weight of 4" Schedule 40 Steel Pipe with Water - SI Units

The outside diameter of 4" Schedule 40 Steel Pipe is *114.3 mm.* The inside diameter is *102.3 mm*. The density of steel is 7*850 kg/m ^{3}*. The density of water is

*1000 kg/m*. The weight per m length of pipe filled with water can be calculated as

^{3}

m=(π / 4) [(7850 kg/m)((0.1143 m)^{3}^{2 }- (0.1023 m)^{2}) + (1000 kg/m) (^{3})0.1023 m^{2}]

= 26.3 kg/m