Tightening Method
Bolted flanges connections - TBSS Method (Tight Between Seal and Strength)

Tightening is the method used to apply tensile force to bolted joints. It must be adapted to sealing requirements, the materials used, the geometry of the joint, as well as accessibility and environmental constraints.

Several methods can be used to apply this preload: torque tightening, elongation tightening, hydraulic tensioning, or deformation control. In the context of standard bolted flange assemblies, the two most common approaches are:

• torque tightening, based on the application of a controlled torque;

• elongation-based tightening, based on the direct measurement of the elastic deformation of the threaded rods.

Each method has its advantages, uncertainties, and limitations. Understanding these methods is essential to ensuring the proper implementation...