(b) Unless otherwise noted, oxide folds and suckbacks are
acceptable if the thickness in the area is not lss than the minimum sheet or
plate thickness allowed in the material specification and/or the drawing tolerance
for machined or formed sheets or parts, whichever is applicable.
(c) Discontinuities exposed to the surface are acceptable
providing the linear dimension and total area values do not exceed the corres-
ponding radiographic limits specified for allnternal discontinuities.
Internal defects - (Radiographic Requirements) The following
internal defects are rejectable:
(a) Cracks are not acceptable in the weld or adjacent base
(b) Porosity, voids and oxide inclusion defects shall be
limited as follows:
(1) Maximum Pore Size: Unconnected voids shall not
exceed a linear dimension greater than 50% of the weld bead thickness or shall
not exceed a diameter of .050 (1/20) inches, whichever is smaller.
(2) The summation of all unconnected void areas in any
linear inch of weld shall not exceed 7% of an area equal to (1 in x T) sq. in.
Aligned porosity shall not exceed 3.5% of an area equal to (1 in. X T) sq. in.
(3) Porosity pores smaller than 0.00008 sq. in. in
area are considered non-detrimental and need not be evaluated.
(4) Weld metal radiograph images which appear to have
pores that overlap, but each pore can be differentiated from the outer by
Radiographic Triangulation, shall be evaluated as separate pores.
Stringer discontinuity- A stringer discontinuity is defined,
for the purpose of X-Ray interpretation, as an oxide stringer, or a series of
stringers in a linear distribution when the ratio of the major dimension to the
minor dimension of an individual discontinuity is 5:1 or greater. The stringer
discontinuity shall be considered a single stringer where the adjacent discontinuities
are not separated by a length equal to or greater than 15% of "T".
A stringer discontinuity is permissible if: The summation
of all connected or aligned stringers do not exceed a total area of 0.060 (60/1000)
sq. in. in any 6.0 inch length of weld and occurs in the weld bead reinforcement
area (root and face).