Nelson Nelweld 4000, Руководство по эксплуатации и обслуживанию

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Nelweld Operations and Service Manual
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reports (CMTR) for each heat and diameter of
steel supplied. These mill test reports certify
compliance to welding code specified material
grades and chemistry, and are available from the
stud manufacturer as part of their certification
package on every shipment of studs made when
requested at the time of purchase.
At the time of manufacture, studs are also tested
to determine that their mechanical properties are
in compliance with welding code requirements.
A certificate of compliance (COC) for each stud
shipment can be made at the time of shipment,
certifying chemical and physical property
compliance
to customer or engineering
specifications sent with the stud purchase order.
COC’s can certify compliance with steel
specifications, such as:
• ASTM – A108
• ASTM – A276
• AWS D1.1, Structural Welding Code – Steel
•
AWS D1.6, Structural Welding Code – Stainless Steel
• Canadian Welding Bureau W59 – Welded Steel
Construction
•
International Standards Organization ISO –13918
Welding Studs and Ceramic Ferrules for Arc Stud
Welding, etc.
Similarly, the weld plate fabricator should require
certified mill test reports from its vendors on steel
purchased for use as base materials in its welding
operations to verify compliance to welding code
approved materials.
Stud manufacturers are
required by welding codes to weld test and
qualify their weld base diameters and materials.
Along with the stud certificates of compliance
and material certified test reports for both studs
and weld plates, the stud weld base qualifications
should be kept on file at the weld plate fabricators
location to verify compliance with quality
programs and welding codes.
2.7.3 Operator Training and Qualification
Operator Training: Introductory training of
operators in the stud welding process is the first
step in successful production stud welding. This
familiarizes the operators with the general
principles of the process, proper set up of the
equipment, weld set up for the studs being used,
general guidelines and inspection techniques.
Highly skilled representatives of Nelson Stud
Welding, Inc. can provide both written and visual
materials as part of a complete program
concluding in formal qualification of both the
operators and the stud welding process.
Process Qualification: Stud welding is a
prequalified process, unique among the many
welding processes due to the many millions of
studs that have been successfully welded with the
process.
When studs are welded in the downhand
position to approved base plate materials,
only two (2) studs are required to be
welded and tested. The test consists of both a
visual inspection and a physical inspection by
bending the studs 30º from the vertical position
by hammering on the unwelded end or bending
with a pipe or other bending device.
If the bend test and visual inspection are both
satisfactory, both the process and the operator are
considered qualified for those stud diameters
welded downhand as long as there are no process
changes. Such changes include those made in the
studs, settings, equipment, welding cables,
ceramic ferrules, or from an approved to a non-
approved base material qualified by the test. The
two-stud test is required at the start of
every
production period such a shift change or operator
change, and if any process changes are made.
Studs welded to a non-approved base plate
material, in the vertical or overhead position, to
the fillet or heel of an angle, etc., must be
application qualification approved by welding ten
(10) of each of the stud styles and diameters to be
used in production in the position(s) and base
materials to be used in production with the same
Stud Qualification Testing
Welding Procedure
No. of Studs to
be Tested
•
Downhand, standard welding
configuration
•
To approved base plate
2
•
Special welding position
• Welding through metal deck
• To non-approved base plate material
10