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INTRODUCTION TO STUDWELDING
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The Taylor Studwelding 800DA Drawn Arc controller when matched with an appropriate
pistol and earth cables is intended for precision stud welding up to 12 mm diameter
reduced base studs. The controller is easily transportable and has been designed to
operate with a minimum amount of maintenance.
The energy required to carry out the welding operation is derived from a fully micro-
processor controlled transformer-rectifier inside the controller.
Taylor Studwelding Systems Ltd pistols are modern, ergonomically designed and offer
maximum comfort in handling with minimum operator fatigue.
THE PROCESS
The process of drawn arc studwelding is long established and well proven. The basic steps
are as follows :
•
A measured amount of weld stud protrusion is set at the welding pistol.
•
Once in position, the pistol lifts the stud away from the work-piece, simultaneously
striking an arc between the two.
•
Both the tip of the weld stud and the surface of the work-piece melt as the arc is
sustained for a pre-determined interval.
•
At the completion of the pre-determined interval, the pistol returns the weld stud to
the molten pool on the work-piece, thus forming a weld.
The most common and traditional drawn arc welds have a weld duration greater than
100ms and employ the use of a single use ceramic arc shield, commonly referred to as a
ferrule. This ferrule helps to protect the arc during the weld and assists in formation of the
final fillet. Post welding the ferrule is removed and disposed of.
It is possible to stud weld without a ferrule. This method is more commonly employed with
welds having a duration of less than 100 ms and this type of weld is referred to as short
cycle stud welding. Although no ferrule is employed, it is recommended practice in short
cycle welding to employ a suitable shielding gas to reduce the amount of porosity in the
completed weld and improve weld quality.
