The theoretical bursting pressure of a pipe determines how much pressure the pipe can withstand without bursting. Theoretical yielding pressure determines how much pressure it can withstand before deforming, though this is typically when a pipe is about to burst. This value is critical knowledge when designing piping systems or determining how much pressure a current pipe can withstand.
Things You'll Need
- Method of measuring pipe thickness and diameter
- Reference materials (American Society of Mechanical Engineers tables or tensile strength charts)
Determine the wall thickness and exterior pipe diameter.
Determine the pipe material strength. This value can be found in the material specifications or in material standards tables by the American Society of Mechanical Engineers (ASME).
Determine the desired safety factor to be used in the equation. For safety purposes, this value should be at least 1.5. Depending on local design codes and the application, the required safety factor may be higher than 1.5. Building codes may mandate safety factors of 2 or higher to prevent property damage caused by burst pipes.
Multiply the wall thickness in inches by the material strength in pounds per square inch by 2.
Divide this value by the outside diameter in inches.
Divide this value by the safety factor. The result is the theoretical pipe bursting pressure at that safety factor.
Tips & Warnings
- If the equation of theoretical bursting or yielding pressure is performed with the safety factor of 1, this is called the bursting pressure. At this pressure and given pipe characteristics, the pipe is certain to burst.
- These equations determine the piping burst pressure based on the piping characteristics. If a piping weld is weaker than the pipe, the weld can give and cause a rupture before mechanical failure of the pipe.
- Rupture disks and pressure relief valves installed in piping will fail at a predetermined pressure and release pressure before piping deforms or bursts. If rupture disks or pressure relief valves have been installed, they will fail at their predetermined pressure rating, regardless of the piping burst pressure. Both of these devices provide a planned point of failure to prevent catastrophe during failure.
- "High Pressure Vessels"; Donald Fryer, John F. Harvey; 1998
- "Companion Guide to the ASME Boiler & Pressure Vessel Code"; K. R. Rao; 2001
- "Standard Handbook of Petroleum and Natural Gas Engineering"; William Lyons, Gary Plisga; 2004
- "Piping and Pipeline Assessment Guide"; A. Keith Escoe; 2006
- "Mechanical Engineering Reference Manual for the PE Exam"; 2006
- Photo Credit burst hose image by Allyson Ricketts from Fotolia.com
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