Operation Manual
12
A5 TIG Orbital System 75© Kemppi Oy 2016 1615
OPERATING MANUAL
3.2.2 Installing the tungsten electrode and holder
To install the tungsten electrode and holder, do the
following:
1. Turn the controller power switch ON.
2. Using the +/- rotation jog on the weld head
handle, rotate the rotor to the open throat area of
the weld head.
3. Using 3 mm x 6 mm cap screws, install the block
and tungsten electrode into desired position. The
tungsten electrode mount block is a split block.
4. Leave screws loose and push tungsten against
the back-up wall on the rotor.
5. Tighten screws, solid side rst, then split side.
The standard position of tungsten electrode as
viewed from the side along the tube centerline is a
5° down from 3 o’clock. This is to avoid breaking of
tungsten when installing on pre-tacked tube. You can use
alternative tapped holes in rotor (8 or 6 o’clock position)
e.g. in case of stripped threads in rotor.
3.2.3 Tungsten electrode geometry guidelines
Tungsten electrode diameter
Use the smallest diameter tungsten electrode suitable
for the weld current range for positive arc ignition and
a stable arc. Thicker diameters handle high currents
and have a greater life at the expense of arc starting.
Recommended Tungsten electrode diameters for
dierent tube wall thicknesses.
Tube wall thickness Tungsten electrode diameter
Up to 1.0 mm 1.0 mm
1.0–2.4 mm 1.6 mm (.062")
2.4–4.0 mm
2.4 mm (0.094”)
Arc gap
The tungsten electrode tip-to-work distance, or arc length
when kept to a minimum, produces a more stable arc and
deeper penetration. For general tube welding, the arc gap
should be adjusted between 0.75 mm and 1.8mm. Table
below is presented recommended tip-to-work distance.
Tube wall thickness Recommended arc length
0.5–1.0 mm 0.75 mm
1.0–2.0 mm 1.3 mm
2.0–4.0 mm
1.8 mm
Tungsten electrode tip angle and at diameter
Tungsten electrode angles (inclination angle) between 15° to 30° enable the most automated welding. Kemppi
recommends 20° for autogenous welding in the general current range used with the 150 series weld heads.
Electrode
Diameter mm
Flat diameter
mm
Included
Angle (deg)
Constant current
Range (amp)
Pulsed current
Range (amp)
1.0 mm 0.25 mm 20° 1
1.6 mm 0.5 mm 20° 8–50 8–100
1.6 mm 0.75 mm 20° 10–70 10–140
2.4 mm 0.75 mm 30° 12–90 12–180
2.4 mm 1.0 mm 30° 15–150 15–250
3.2 mm 1.0 mm 30° 20–200
20–300