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9 Welding Process
9
Welding Process
Stud welding with a drawn arc process is divided into drawn-arc stud welding with
ceramic ferrule and drawn-arc stud welding with shielding gas. This power unit must
be used exclusively for stud welding with drawn arc.
The face of a stud-shaped welding element and the opposite surface of the workpie-
ce are molten by an arc. Stud welding is suitable for the welding of joining elements
across the entire cross-section, mainly using pin-shaped metallic welding elements
with metallic workpieces.
The various processes of arc stud welding are distinguished by:
– The method of weld pool protection (shielding gas - SG, ceramic ferrule - CF or no
protection - NP)
– The length of welding time (standard ARC or short-cycle drawn-arc stud wel-
ding - SC)
–
The energy source (welding rectifier supplied by mains, inverter, capacitor battery).
Drawn-Arc Stud Welding
The HBS stud welding unit operates by process of ‘arc stud welding with drawn-arc
ignition’ according to the current standards. The standards assign this method of
joining pin-shaped elements with plane workpieces to the so called ‘Arc Pressure
Welding’ (code BH).
Joining is carried out in plastic or liquefied condition of the welding zone. The pro
-
cess can be carried out mechanically or automatically, depending on the used wel-
ding guns/welding heads.
Generally, the positive pole of the power unit is connected to the workpiece. The
welding element is manually or automatically inserted into the chuck of the welding
gun or of the welding head. Then it is placed onto the workpiece - possibly equipped
with a ceramic ferrule (see figure,
position 1
). When the button of the welding gun
is triggered, the automated welding process starts, which works as follows:
Summary of Contents for 93-10-1552A
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