Radiographic inspection ratio for the butt welds between the flanges and shell sections of heat exchanger equipment
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The heat exchanger shell is made of seamless steel pipes. On the general layout, the weld joint factor for types A and B is set at 0.85. Should the butt welds between the equipment flanges and the connecting pipes in the shell be inspected using 100% RT or 20% RT? Which one is everyone following?
In our company, 0.85 corresponds to 20%, while 1.0 corresponds to 100%. For specific details, refer to GB150 P13 4. 5.2 The welding joint coefficients are described in great detail
In our company, 0.85 corresponds to 20%, while 1.0 corresponds to 100%. For specific details, refer to GB150 P13 4. 5.2 The welding joint coefficients are described in great detail
Under normal circumstances, except in cases where substances such as water and air are non-toxic and non-explosive, and where strict requirements regarding leakage sealing are not necessary, a 20% inspection rate can be applied for Type B seams, with Grade III considered acceptable； However, for special equipment (other than air tanks, water tanks, collectors, etc.), a 100% rate is still recommended, although the acceptance criteria for Grade II require a higher rating ； It doesn’t have many episodes either.
No longitudinal welds; Category A can be crossed out and not included. For Class B welds, circumferential welds generally do not play a controlling role. However, the pipes commonly used are usually quite thin, and there isn’t much difference between 100% and 20%. We have all set it to 100%, and the coefficient for Class B welds should be filled in as 1.
Is the butt weld between the equipment flange and the shell section classified as 47023? I believe that standard requires 100% inspection for such welds
Are there any other additional conditions under which 100% testing is required?