5. Modifications and repairs

Repairs or modifications to pressure equipment mainly involve welding.

These operations require knowledge of the manufacturing characteristics of the ESP concerned (materials used, any heat treatments, minimum design thicknesses, controls, service conditions).

They are carried out in accordance with the rules applicable to new equipment (design, construction, inspections).

In certain special cases (e.g. work on ESPs which have undergone an initial heat treatment which cannot be repeated under conditions which do not affect the metallurgical characteristics of the steel), specific procedures may be used (see, for example, the American ASME PCC2 Post Construction Code).

In the case of major equipment (such as LPG storage vessels), the pre-intervention study should give priority to solutions...