.Welding on a single workpiece using multiple welding power sources can cause arc blow and arc impedance to develop or intensify.
5-4. Using Multiple Welding Power Sources
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| 1 | Welding Power Source |
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| 2 | Electrode Cable |
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| 3 | Feeder Cable | |
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| 4 | Work Cable |
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| 5 | Voltage Sensing Lead |
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| 6 | Wire Feeder |
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| 7 | Workpiece | |
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| Each welding power source should | |
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| have a separate work cable connection | |
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| to the workpiece. Do not stack or join | |
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| work cables together at the workpiece. | |
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| This is very important for pulse welding | ||
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| applications. | |
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| It is important to connect the voltage | |
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| sensing lead as near to the weld as | |
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| possible, but not in the return current | |
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| path. | |
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| Connect voltage sensing lead at the end | |
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| of the weld joint. | |
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| The direction of the welding path should | |
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| be away from the work cable | ||
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| connections. | |
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| Connect work clamp at the beginning of | |
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| the weld joint. | |
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| Each welding gun should have its own | |
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| source of shielding gas. Use a separate | |
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| 1 | shielding gas regulator and shielding | |
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| gas connection for each welding gun. | ||
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| Arc blow is the deflection of a welding | ||
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| arc from its normal path due to magnetic | |
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| forces. It will adversely affect the | |
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| appearance of a weld, cause excessive | |
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| spatter, and impair the quality of a weld. | |
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| Arc blow occurs primarily during the | |
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| welding of steel or ferromagnetic | |
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| metals. Weld current will take the path of | |
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| least resistance, but not always the | ||
Gun |
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| most direct path through the workpiece | ||
Travel |
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| to the work lead connection. The most | ||
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| intense magnet force will be around the | ||
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| arc due to a difference in resistance for | |
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| the magnetic path in the base metal. | ||
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| The work clamp connection is important | ||
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| and should be placed at the starting | |
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| point of a weld. It is recommended to | |
4
Current Flow Path
have as short of an arc as possible so that there is less of an arc for the magnetic forces to control. Conditions affecting the magnetic force acting on the arc vary so widely that the reference
here is only about cabling connections
and arc preferences.
Ref. 804