least 90 percent must be examined. Nondestructive examination must be
impracticable for each girth weld not examined.
a.
At onshore locations where a loss of hazardous liquid (petroleum,
petroleum products, or anhydrous ammonia) could reasonably be
expected to pollute stream, river, lake, reservoir, or other body
of water, and any offshore area;
b.
Within railroad or public road rights-of-way;
c.
At overhead road crossings and within tunnels;
d.
Within the limits of any incorporated subdivision of a State
government; and
e.
Within populated areas, including, but not limited to, residential
subdivisions, shopping centers, schools, designated commercial
areas, industrial facilities, public institutions, and places of
public assembly.
3.5
ACCEPTANCE STANDARDS
**************************************************************************
NOTE: These acceptance standards are taken from
ASME B31.1 and are suitable for most jobs.
Evaluations of indications as given in ASME B31.1
are applicable to these standards. Visual
acceptance standards are given for some other piping
codes. It should be noted that specific project
design requirements may necessitate revision or
expansion to cover different items of work and
varying standards of acceptance.
**************************************************************************
3.5.1
Visual
The following indications are unacceptable:
a.
Cracks--external surface.
**************************************************************************
NOTE: In the text below, if only ASME B31.3 is
applicable, delete all text in brackets. For ASME
B31.3 under normal service conditions, use 25
percent with text in brackets and omit last sentence
in brackets. For ASME B31.4 use 12.5 percent, and
add the material in brackets pertaining to B31.4.
Consider use of ASME B31.1 acceptance standard for
codes other than B31.3 and B31.4.
**************************************************************************
b.
Undercut on surface which is greater than 1.00 mm 1/32 inchdeep
[or [25 percent for ASME B31.3] [and] [12.5 percent for ASME B31.4
and ASME B31.9] of the wall thickness, whichever is less,]
provided that the remaining wall thickness is not less than the
minimum design thickness. [For ASME B31.4 and in accordance with
API Std 1104, undercuts over 0.40 mm through 0.80 mm 1/64 inch
through 1/32 inch or over 6 to 12.5 percent of the pipe wall
thickness, whichever is smaller, shall not exceed 51 mm 2 inches
SECTION 15216N
Page 16
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