controlled temperature storage oven shall be used at the job site
as prescribed by AWS D1.1/D1.1M, Subsection 4.5 to maintain low
moisture of low hydrogen electrodes.
(2) Preheat and Interpass Temperature - Preheating shall be
performed as required by AWS D1.1/D1.1M, Subsection 4.2 and 4.3 or
as otherwise specified except that the temperature of the base
metal shall be at least 20 degrees C 70 degrees F. The weldments
to be preheated shall be slowly and uniformly heated by approved
means to the prescribed temperature, held at that temperature
until the welding is completed and then permitted to cool slowly
in still air.
(3) Stress-Relief Heat Treatment - Where stress relief heat
treatment is specified or shown, it shall be in accordance with
the requirements of AWS D1.1/D1.1M, Subsection 4.4 unless
otherwise authorized or directed.
d. Workmanship - Workmanship for welding shall be in accordance with
AWS D1.1/D1.1M, Section 3 and other applicable requirements of these
specifications.
(1) Preparation of Base Metal - Prior to welding the Contractor
shall inspect surfaces to be welded to assure compliance with AWS
D1.1/D1.1M, Subsection 3.2.
(2) Temporary Welds - Temporary welds required for fabrication
and erection shall be made under the controlled conditions
prescribed for permanent work. Temporary welds shall be made
using low-hydrogen welding electrodes and by welders qualified for
permanent work as specified in these specifications. Preheating
for temporary welds shall be as required by AWS D1.1/D1.1M for
permanent welds except that the minimum temperature shall be 50
degrees C 120 degrees F in any case. In making temporary welds
arcs shall not be struck in other than weld locations. Each
temporary weld shall be removed and ground flush with adjacent
surfaces after serving its purpose.
(3) Tack Welds - Tacks welds that are to be incorporated into the
permanent work shall be subject to the same quality requirements
as the permanent welds and shall be cleaned and thoroughly fused
with permanent welds. Preheating shall be performed as specified
above for temporary welds. Multiple-pass tack welds shall have
cascaded ends. Defective tack welds shall be removed before
permanent welding.
2.2.2.2
Welding of Steel Castings
Unsound material shall be removed from the surfaces of steel castings to be
incorporated into welded connections by chipping, machining, air-arc
gouging or grinding. Major connections designed for transfer of stresses
shall not be welded if the temperature of the casting is lower than 40
degrees C 100 degrees F. Castings containing over 0.35 percent carbon or
over 0.75 percent manganese shall be preheated to a temperature not to
exceed 230 degrees C 450 degrees F and welding shall be accomplished while
the castings are maintained at a temperature above 180 degrees C 350
degrees F. Welding will not be permitted on castings containing carbon in
excess of 0.45 percent except on written authorization. Castings requiring
welding repairs after the first annealing and castings involving welding
SECTION 05055A
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