degrees F for 12 hours. Following the 12 hour soak, flush the system with
fresh water at not less than 15.50 degrees C 60 degrees F for 4 hours.
3.3
FIELD QUALITY CONTROL
3.3.1
Examinations
3.3.1.1
Welding Examinations
[The Contractor shall] [The Government will] perform visual examinations to
detect surface and internal discontinuities in completed welds. NDE on
piping welds covered by ASME B31.9 is visual inspection only. Verify
piping welds meet the acceptance criteria. Submit a NDE report meeting the
requirements specified in ASME B31.9. Visually examine all welds. When
examination indicates defects in a weld joint, the weld shall be repaired
by a qualified welder. Remove and replace defects as specified in ASME B31.1,
unless otherwise specified. Repair defects discovered between weld passes
before additional weld material is deposited. Whenever a defect is
removed, and repair by welding is not required, blend the affected area
into the surrounding surface, eliminating sharp notches, crevices, or
corners. After defect removal is complete and before rewelding, examine
the area by the same methods which first revealed the defect to ensure that
the defect has been eliminated. After rewelding, reexamine the repaired
area by the same test methods originally used for that area. Any
indication of a defect shall be regarded as a defect unless reevaluation by
surface conditioning and reexamination shows that no unacceptable defects
are present. The use of any foreign material to mask, fill in, seal, or
disguise welding defects will not be permitted.
3.3.1.2
Brazing Examinations
The Contractor shall perform brazing examinations.
Visually examine all
compressed air systems as follows:
a.
Check brazed joint fit-up. Diametrical clearances shall conform
to brazing procedure requirements.
b.
Check base material of pipe and fitting for conformance to the
applicable drawing or specification.
c.
Check grade of brazing alloy for conformance to the brazing
procedure before fit-up or brazing.
d.
Check completed brazed joint for a complete ring of brazing alloy
between the outside surface of the pipe and the face of the
fitting, and for a visible fillet.
e.
Check stainless steel and other susceptible material for evidence
of stress cracks. Check inside of joint if possible with
borescope or other aids.
Defective joints may be repaired. However, no more than two attempts to
repair by reheating and additional face feeding of brazing filler metal
will be permitted, after which the defective joint shall be unsweated,
reprepared as a new joint, examined for defects on pipe and fittings, and
rebrazed.
SECTION 15211N
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