Pressure carrying capacity of a hose

[Marts12]

Hi There,

Why is a pipe with a smaller diameter able to withstand a greater internal pressure than a pipe made from the exact same material and wall thickness but larger diameter?

Thank you

 

[boneh3ad]

Are you familiar with the concept of hoop stress? Basically, there is more internal area upon which the pressure acts, which means a larger total pressure force. If the wall thickness is the same, that larger force is distributed over the same amount of tubing material, so it experiences higher stress.

 

[stockzahn]

Calculate it! Let's do the tangential stresses:

$d$ ... inner diameter of the pipe
$l$ ... length of the pipe
$t$ ... wall thickness
$\Delta p$ ... pressure above ambient pressure in the pipe

The force taken by the pipe walls equal the force due to the (over)pressure in the pipe.

 

[Marts12]

Thank you both this is exactly what I needed.