Flexibility analysis is an analysis of the ability of pipe to change its length and deform elastically. This condition occurs because of load which is affected by high temperature during operation in piping system. Piping system must be enough flexible so thermal expansion or movement of support or end point of pipe will not cause as follow:
- Leakage in welded joint pipe.
- High stress or distortion which cause damage to connected equipment such as pump, tank or valve because excessive force and moment in the pipe.
Furthermore, if the piping system has enough flexibility, so the pipe will experience changes in length due to thermal expansion or contraction and able to return to the initial length when the load due to expansion or contraction is eliminated.
In the Code ASME B31.3 flexibility analysis in the piping system is regulated in paragraph 319.4. Code ASME B31.3 specify special requirement of flexibility in the piping system as follow:
- Range calculation stress because of displacement in every point of piping system should not exceed the allowable stress.
- The calculation of reaction force should not damage to support or connected equipment in piping system.
- The calculation of displacement should not exceed the limitation range in ASME Code B31.3