Today, manufacturing companies and especially those that focus on automotive, aerospace and consumer needs to apply precise and validated torque to the large number of bolted joints they have in their products. For the application of torque there are several theories very complete because it is a very critical process for the final quality of the product.
Torque theories can become complex because you need to have a preliminary engineering knowledge, just like a company education for the application of this. Each torque needs to enter certain specifications of applied force so that to know if the applied torque is inside these, it is necessary to audit the residual torque. The residual torque refers to knowing the force that is in the bolted union after being tightened.