The load cases displayed below are only for wind acting in one direction, that is, +X. Depending on the system, the most critical loads could occur in any direction +/-X, +/-Z, or skewed in XZ. The intention of the load case construction is to find the effect of the occasional load on the piping system in the operating condition. Determining the proper load ratings for underground pull boxes is critical to ensuring public safety. The following article is designed to help you understand what factors to consider in choosing the proper traffic rating for pull boxes and covers. The wall thickness of pipe is nearly always selected based on the thickness required for internal pressure and allowances. The piping is then supported sufficiently such that the longitudinal stress (this is the stress in the axial direction of the pipe) is within Code limits and deflection is within acceptable limits.

1. Natural phenomena such as hurricanes and earthquakes will cause excitation force against the pipe that is dynamic. Dynamic analysis on piping system is needed to get the stress distribution caused by dynamic loads which occur in piping system.
2. Snow, occur in the piping system located on the earth which experience winter. Concentration buildup of snow is very thick in certain parts along the piping system will lead to the imposition of excessive weight that must be retained by the piping system.
3. Postulate plant accident, an accident occurred on the piping system that arise by certain causes whether from the operator or from a third party (third party damage).
4. Unusual plant operation, an error occurs in the operating conditions are made possible by negligence of the operator or procedural error in operating the piping system.

Occasional loads B31.3

Occasional loads B31.3

Occasional Load Shedding

Occasional Loader