Torsional deflection refers to the twisting of one end of a bellows relative to the other about its centerline. Metallic expansion joints are inherently not designed to absorb torsional movement, making it critical for piping designers to incorporate proper restraints that prevent torsional loading from reaching the expansion joint. Metallic Bellows elements are essentially inflexible in this direction, and should be avoided, as excessive torsional loads can cause serious damage if left unaddressed. At US Bellows, our catalog provides calculated torsional spring rates for each pipe expansion joint, giving designers accurate inputs for piping flexibility analysis. Where torsional loads cannot be eliminated, our engineers can incorporate anti-torsion features to protect the bellows element.
Torsion refers to twisting one end of the bellows with respect to the other end, about the bellows centerline. Pipe expansion joints are not normally expected to accept torsional deflection since the bellows are essentially inflexible in this direction. The piping designer should carefully provide the system with restraints so that the pipe expansion joint is not expected to accept TORSIONAL DEFLECTION. This catalog contains the calculated torsional spring rate for each pipe expansion joint so that piping designers and analysts can provide the proper inputs for piping flexibility computer programs. If it is not possible or economically practical to relieve the pipe expansion joint of excessive torsional loading, then PT&P’s designers can provide anti-torsion features to the pipe expansion joints which prevent these loads from damaging the bellows elements.