(4) Stamp identification on steel so film may be easily
identified and matched to identification mark.
b.
Ultrasonic Testing of Welds
(1)
Inspection methods shall be in accordance with ASTM E 164.
(2) Size of defects will be determined by relating amplitude of
oscilloscope traces to hole in ASTM reference weldment.
(3)
Diameter of reference holes shall be 2.4 mm 3/32-inch.
(4) Weld defects which are cause for rejection include cracks,
lack of fusion, incomplete penetration, porosity, or slag
inclusions which produce reflections equal to or greater than 80
percent of reference hole reflection and have linear dimensions as
indicated by transducer movement exceeding following:
(a) 6 mm 1/4-inch for material thickness up to and including 19
mm 3/4-inch.
(b) 8 mm 1/3-inch for material thickness over 19 mm 3/4-inch up
to and including 57 mm 2-1/4 inch.
(c)
19 mm 3/4-inch for thickness over 57 mm 2-1/4 inch.
3.1.2.2
Correction of Defective Welds
Repair weld areas containing defects; additional tests of repaired areas
shall be made at Contractor's expense. If 20 percent or more of welds made
by a given welder contain defects requiring repair, 100 percent
nondestructive inspection of that welder's work will be required at
Contractor's expense.
3.2
TREATMENT PLANT CONSTRUCTION
All work not absolutely required to be performed in the field shall be
performed in a factory under controlled conditions. The treatment plant
shall be fabricated from not less than 6 mm 1/4-inch steel plate with
welded joints and shall be reinforced as necessary with steel angles, tees,
or other structural members. The units shall be designed and constructed
for transportation, installation, and operation without detrimental
buckling, distortion, or other defects. Tanks shall not leak when filled
with water or sewage.
3.2.1
Pipe and Valve Installation
Piping shall be installed in a neat manner with all joints tight and with
no undue marring of finishes. Installed piping, valves, and fittings shall
be free from strain and excessive stresses caused by weight or misalignment.
3.2.1.1
Bolts shall be tightened uniformly to prevent overstressing flanges and
misalignment.
SECTION 11390
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