Is 100% radiographic inspection required for welds of fittings smaller than DN150?
Thread Content
The cylinder is subject to 100% radiographic inspection. The cylinder has nozzles, with diameters less than DN150. Are the Class B welds of the nozzles and elbows also required to undergo 100% radiographic inspection?
Determined by the designer; surface inspection in accordance with the requirements of GB150 standard is sufficient.
The standard only requires surface inspection; a 100% RT check is not mandatory
What if it’s not specified on the drawing? In my opinion, the Class AB welds specified in the technical parameters table refer only to the cylinder body and do not include the nozzles, right?
Designers generally need to consider the effects of medium properties, pressure, temperature, etc., requiring stringent radiographic inspection for critical applications and routine surface inspection for others.
For DN250 and below, surface probes are generally used; controlling the construction process is key!
For pipe fittings below DN250, Class B joints are used; if not specified in the design documents, RT is not required
For pipe fittings below DN250, Class B joints are used; if not specified in the design documents, RT is not required
It should also include fittings with DN≥250.