Proof Load Test
The test concerns the screws and involves subjecting the component to be tested to tension or compression by applying the load with a certain speed and for a certain time interval. The component and the thread must not break or crack and it must be possible to remove the screw manually, loosening it by a maximum of half a turn with a wrench.

Pull Out

This is a tensile or compression test performed on the tube sheets to check their welds.

Nick Break Test

It consists in subjecting to mechanical stresses (traction or percussion with a hammer) and breaking a specimen obtained near a suitably notched weld bead. At the end of this operation, the parts of the sample are examined in order to verify the full penetration and the possible presence of gas bubbles, porosity, slag or other defects that could, due to size and concentration, affect the quality of the weld.

Shear resistance

The shear test consists of applying a stress to a test specimen so that it produces a sliding failure along a plane parallel to the applied forces.