UT Should carried out as per article 5 of ASME Sec.
V.
UT examination shall be performed in accordance with
the written procedure certified by Manufacturer to be in accordance with the
requirements of T-150 of ASME Sec. V
UT Personnel shall be qualified and certified in accordance
with employer’s acceptance, as per SNT- TC-1A
Acceptance standards (UT)
These standards shall apply unless other standards
are specified for specific application as specified in the PO Specifications.
Imperfections which produce a response greater than
20% of the reference level shall be investigated to the extent that operator
can determine shape, identity and location of all such imperfections and
evaluate them in terms of the acceptance standards given below.
Indications characterized as cracks, lack of fusion
or incomplete fusion are unacceptable regardless of length.
Other imperfections are unacceptable if the
indications exceed the reference level amplitude and have lengths which exceed:
¼” for t up to ¾”
1/3t from ¾” to 2 ¼”
¾” for t over 2 ¼
Where, t is the thickness of the weld excluding
allowable reinforcement.
For a butt weld joining two members having different
thickness at the weld, t is the thinner of those two thicknesses. If a full penetration
weld includes a fillet weld, the thickness of the throat of the fillet weld
shall be included in t.
Report of UT including repaired areas and results of
reexamination, duly verified by the inspector shall be retained by the
manufacturer and incorporated in MDR
Comments
Post a Comment