accordance with paragraph entitled "Welding Procedure Qualifications."
Include results of ultrasonic test and hardness tests. Welders
certification or procedure qualification may be substituted, pursuant to
paragraph entitled "Quality Assurance."
1.4
DELIVERY AND STORAGE
Deliver materials in the manufacturer's original unbroken packages or
containers plainly labeled with the manufacturer's name and brand.
1.4.1
Receipt Inspection of All Thermite Weld Kits
Shall consist of a visual inspection of the weld kit package for freedom
from damage and the recording of the thermite weld mix batch number and
manufacturing date. Do not use kits which have been manufactured more than
2 years before the date of use or show signs of having been wet.
1.4.2
Store materials in the original package and keep dry at all times until
used.
PART 2
PRODUCTS
2.1
MATERIALS
Provide in kit form including preformed mold, thermite powder, wicking
cord, luting material, and all necessary materials and accessories needed
to provide one welded rail joint per kit. Molds shall be factory-made,
moisture free, and of nonhygroscopic material.
PART 3
EXECUTION
3.1
SEQUENCE OF OPERATION
Perform work in strict accordance with the qualified procedure.
3.1.1
Rail Preparation
Cut rails which are battered, cracked or notched, or which contain bolt
holes so that these irregularities are removed. Rail surface shall be free
of grease, dirt, loose oxide, and moisture on the face of and for
approximately 125 mm 5 inches from the joint to be welded. Clean rail ends
by grinding or wire brushing. Use a torch to remove grease, oil, or
moisture in accordance with procedures in thermite manufacturers
instructions. Rail cutting, when necessary, shall be by the saw-cut
method. Remove all burrs, rolled-over edges, and loose oxide before
applying the mold. No flame cutting of rails is permitted. If the space
between the mold and the rail is unusually large on used or relayer rails,
fill this gap with a piece of wicking cord before luting or packing.
3.1.2
Rail Alignment
Separate rail ends as recommended by the welding process manufacturer.
Align rails as to both surface and gage, and raise the rails at the joint
to compensate for the greater thermal contraction that occurs in the rail
head during cooling relative to the web and base regions. Measure the
amount of joint elevation with a 900 mm 36 inch long straightedge centered
at the joint. The correct elevation is obtained when 2 mm 1/16 inch
SECTION 05652N
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