OPERATING & MAINTENANCE INSTRUCTION MANUAL
MODELS 427A (R-1), 428A (R-2), AND 429A (R-3) WELD HEADS
REV. AB
MODEL 514 TUBEMASTER OR 515/516 PIPEMASTER POWER SUPPLY
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THESE DOCUMENTS, AND THE CONTAINED INFORMATION HEREIN, ARE PROPRIETARY AND ARE NOT TO BE REPRODUCED, USED OR DISCLOSED TO
OTHERS FOR MANUFACTURE OR FOR ANY OTHER PURPOSE, EXCEPT AS SPECIFICALLY AUTHORIZED, IN WRITING, BY MAGNATECH, LLC
12.0
DEVELOPING WELD PROCEDURES/PROCESS PARAMETERS
12.1
Goal
The following will hopefully assist the customer in development of process parameters which will meet the
requisite weld quality requirements in the most economical fashion. A second, but equally important, goal is
to develop procedures/parameters that will be as "forgiving" as possible to real-world tolerances in
variations such as:
Joint fit up
Bevel geometry tolerances
Gravity position
Torch tracking errors
Specific problems associated with the work piece alloy
The comments in this section are general, and some of them may not be applicable, depending on the
actual model of power source/controller supplied with the Weld Head.
12.2
MECHANIZED VERSUS MANUAL: IMPLICATIONS TO WPS/PQR
Summary:
If a WPS/PQR exists for manual welding, a change to mechanized welding does not require a
new WPS/PQR to be established. Welders will qualify as "welding operators" instead of welders under the
Welder Performance Qualification test.
There is a misconception by many people that the substitution of mechanized pipe welding for manual
techniques requires that a new Procedure Qualification Record (PQR) be done (as well as the Weld
Procedure specification that it supports). This is not the case. The ASME code, Section IX, defines welding
variables under Section QW-250. Nonessential variables are subsequently defined in Section QW-251.3.
Nonessential variables:
“Nonessential variables are those in which a change, as described in the specific variables, may be made in
the WPS without requalification.”
The specific variables for gas metal arc welding (GMAW) are defined under QW-255. Nonessential
variables are listed under 255.2 for GMAW. Variables for gas tungsten arc welding (GTAW) are listed under
QW-256. Nonessential variables are listed under the subheading 256.2. Both QW-255 and QW-256 list
QW-410.25 as a nonessential variable.
QW-410.25: "A change from manual to semi-automatic to machine automatic welding and vice-versa."
Joint design including bevel geometry and fit-up gap are nonessential variables for both GTAW and GMAW
weld processes as defined by QW-415 welding variables.
In summary, the use of Magnatech's Mechanized Orbital TIG and MIG Pipe Welding Systems do not require
a new Procedure Qualification Record and attendant Weld Procedure Specification. For the individual
Welder Performance Qualification test, the welder would qualify as a "Welding Operator" instead of as a
"Welder".
