Telwin MasterMIG 405i Bedienungsanleitung Seite 8

Carbon, low-alloy steel
- Usable wire diameter:
- Usable gas:
Stainless steel
- Usable wire diameter:
- Usable gas:
Aluminium and CuSi/CuAl
- Usable wire diameter:
- Usable gas:
PROTECTION GAS
See TAB. 2.
7. MIG-MAG OPERATION MODE
The wire feeding speed and the welding voltage are adjusted separately. The knob (Fig. C-5)
adjusts the welding voltage, while the knob (Fig. C-6) adjusts the wire feeding speed. The
voltage value set is indicated on display V (Fig. C-7), as is the wire feeding speed (Fig. C-9).
NOTE: when setting the welding voltage, an approximate current value is also displayed for
a few seconds on display A (Fig. C-8). The real welding current will be shown on the display
only during welding.
When welding is complete, the current remains visible for a few seconds.
With reference to the table available on the machine (Tab. 2) set the knobs (Fig. C-5 and
C-6) according to the material, wire, gas and thickness you intend welding (approximate
values for the most used wires and with the welding machine connected to a 400V - 3ph
power system).
The secondary knob (Fig. C-4) adjusts the inductance value. The lower the inductance level
( ) the harder the arc, the higher the inductance level (
little projection. For welding of carbon and low-alloy types of steel with Ar/CO
gas, use an intermediate inductance value (
7.1 Torch push-button control mode (Fig. C-3)
It is possible to set 2 different torch push-button control modes:
2T Mode
welding begins when the torch push-button is pressed and ends when the push-button is
released.
4T Mode
welding begins when the torch push-button is pressed and released, and ends only when the
torch push-button is pressed and released a second time. This mode is useful for long welding
operations.
8. MMA WELDING: PROCESS DESCRIPTION
8.1 GENERAL PRINCIPLES
- It is essential to follow the recommendations provided by the manufacturer on the electrode
packaging which indicates the correct electrode polarity and relative rated current.
- Welding current is regulated to suit the diameter of the electrode being used and the type
of soldering to be performed; an example of the currents used for the various electrode
diameters can be seen below:
Ø Electrode (mm)
1.6
2.0
2.5
3.2
4.0
5.0
6.0
8.0
- One can see that for the same diameter electrode, high levels of current will be used for flat
welding, whilst lower current levels will be used for vertical or overhead welding.
- The mechanical characteristics of the welded joint are determined by the intensity of the
selected current and also other welding parameters such as the length of the arc, the
operating speed and position, the diameter and quality of the electrodes (to ensure correct
conservation, use special packaging or containers to store and protect the electrodes against
humidity).
ATTENTION:
Instability of the arc due to the composition of the electrode can occur, depending on
the brand, type and thickness of the electrode coatings.
8.2 PROCEDURE
- Keeping the mask IN FRONT OF YOUR FACE, rub the tip of the electrode on the piece to be
welded, moving as if striking a match; this is the most correct method for igniting the arc.
ATTENTION: DO NOT TAP the electrode against the workpiece, which could damage the
coating and make arc striking difficult.
- As soon as the arc has struck, try to keep the electrode at a distance from the workpiece that
is equivalent to the diameter of the electrode being used, and keep this distance as constant
as possible while welding; remember that the electrode angle while moving forward must
be approx. 20-30 degrees.
- At the end of the welding seam, take the electrode end slightly back as to the forward
direction, above the crater to fill it, then quickly lift the electrode from the weld pool to
switch off the arc (Aspects of the welding seam - FIG. I).
8.3 Setting of parameters
Machine setting selector (Fig. C-3):
: MMA mode.
- Adjust the welding current to the desired value using knob C-5;
- The set value is shown on the display A (Fig. C-8);
- The welding voltage is shown on the display V (Fig. C-7) only during welding;
- When welding is complete, the voltage remains visible for a few seconds;
- Adjust the value of the "DYNAMIC ARC" dynamic overcurrent using the secondary knob C-4.
With low arc force levels (DYNAMIC ARC) the arc will be softer (
high arc force levels (DYNAMIC ARC) the overcurrent in welding will be higher (
setting improves welding fluidity, prevents the electrode from sticking to the workpiece and
makes it possible to use different types of electrodes.
9. TIG DC WELDING: PROCESS DESCRIPTION
9.1 GENERAL PRINCIPLES
TIG DC welding is suitable for all types of low-alloy and high carbon steel, and heavy metals
0.6 - 0.8 - 0.9 - 1.0 - 1.2 mm (1.6 mm version 400A only)
CO or Ar/CO
2
0.8 - 0.9 - 1.0 - 1.2 mm (1.6 mm version 400A only)
Ar/O or Ar/CO mixtures (1 - 2%)
2 2
0.8 - 1.0 - 1.2 mm
) the softer the arc with
).
Welding current (A)
Min. Max.
30
40
60 110
90 140
120 180
170 250
230 350
320 500
), on the contrary with
such as copper, nickel, titanium and their alloys (FIG. L). An electrode with 2% Cerium (grey
band) is normally used for TIG DC welding with electrode at the (-) pole. The tungsten electrode
must be axially sharpened using a grinding wheel, see FIG. M; make sure the tip is perfectly
mixtures
2
concentric to prevent arc deviation. The electrode must be ground along its length. This
operation must be repeated periodically according to the use and wear state of the electrode,
or when the electrode itself has been accidentally contaminated, oxidised or used incorrectly.
For good welding, it is indispensable to refer to TAB. 6 which indicates the diameter of the
electrode, current and gas flow based on the thickness you intend welding. The electrode
normally projects from the ceramic nozzle by 2 - 3mm, but can reach 8 mm for welding edges.
Ar
The weld is created by the edges that melt. Filler metal is not needed when welding suitably
prepared thin material (up to about 1 mm) (FIG. N).
A greater thickness requires rods made from the same material as the basic material and with
a suitable diameter, with edges that have been suitably prepared (FIG. O).
For welding to be successful, the pieces must be carefully cleaned and free from oxide, grease,
oil, solvent, etc.
9.2 PROCEDURE (LIFT STRIKE)
Machine setting selector (Fig. C-3):
: TIG mode.
- Use the knob C-5 to adjust the welding current to the required rate; adjust this value during
welding processes to adapt to the actual heat transfer required.
- The set value is shown on the display A (Fig. C-8).
- The welding voltage is shown on the display V (Fig. C-7) only during welding.
- When welding is complete, the voltage remains visible for a few seconds.
- Make sure the gas is flowing correctly.
The arc ignites through contact, distancing the tungsten electrode from the workpiece.
Igniting in this manner causes less electric-irradiated disturbances and reduces tungsten
protection
2
inclusions and electrode wear to a minimum.
- Place the tip of the electrode on the workpiece, pressing gently.
- Immediately lift the electrode by 2 - 3mm to obtain the arc strike.
The welding machine initially supplies reduced current. After a few seconds, the set welding
current is issued.
- Quickly lift the electrode from the workpiece to interrupt welding.
10. MAINTENANCE
WARNING! BEFORE CARRYING OUT MAINTENANCE OPERATIONS MAKE SURE
THE WELDING MACHINE IS SWITCHED OFF AND DISCONNECTED FROM THE
MAIN POWER SUPPLY.
10.1 ROUTINE MAINTENANCE:
ROUTINE MAINTENANCE OPERATIONS CAN BE CARRIED OUT BY THE OPERATOR.
10.1.1 Torch
- Do not put the torch or its cable on hot pieces; this would cause the insulating materials to
melt, making the torch unusable after a very short time.
- Make regular checks on the gas pipe and connector seals.
- Accurately match collet and collet body with the selected electrode diameter in order to
avoid overheating, bad gas diffusion and poor performance.
- At least once a day check the terminal parts of the torch for wear and make sure they are
assembled correctly: nozzle, electrode, electrode-holder clamp, gas diffuser.
- Before using the welding machine, always check the terminal parts of the torch for wear
50
and make sure they are assembled correctly: nozzle, electrode, electrode-holder clamp, gas
80
diffuser.
10.1.2 Wire feeder
- Make frequent checks on the state of wear of the wire feeder rollers, regularly remove the
metal dust deposited in the feeder area (rollers and wire-guide infeed and outfeed).
10.2 EXTRAORDINARY MAINTENANCE
EXTRAORDINARY MAINTENANCE MUST ONLY BE CARRIED OUT BY TECHNICIANS WHO
ARE EXPERT OR QUALIFIED IN THE ELECTRIC-MECHANICAL FIELD, AND IN FULL RESPECT
OF THE IEC/EN 60974-4 TECHNICAL DIRECTIVE.
WARNING! BEFORE REMOVING THE WELDING MACHINE PANELS AND
WORKING INSIDE THE MACHINE MAKE SURE THE WELDING MACHINE IS
SWITCHED OFF AND DISCONNECTED FROM THE MAIN POWER SUPPLY
OUTLET.
If checks are made inside the welding machine while it is live, this may cause serious
electric shock due to direct contact with live parts and/or injury due to direct contact
with moving parts.
- Inspect the welding machine regularly, with a frequency depending on use and the
dustiness of the environment, and remove the dust deposited on the transformer, reactance
and rectifier using a jet of dry compressed air (max. 10 bar).
- Do not direct the jet of compressed air on the electronic boards; these can be cleaned with a
very soft brush or suitable solvents.
- At the same time make sure the electrical connections are tight and check the wiring for
damage to the insulation.
- At the end of these operations re-assemble the panels of the welding machine and screw the
fastening screws right down.
- Never, ever carry out welding operations while the welding machine is open.
- After having carried out maintenance or repairs, restore the connections and wiring as they
were before, making sure they do not come into contact with moving parts or parts that can
reach high temperatures. Tie all the wires as they were before, being careful to keep the high
voltage connections of the primary transformer separate from the low voltage ones of the
secondary transformer.
Use all the original washers and screws when closing the casing.
11. TROUBLESHOOTING
IN CASE OF UNSATISFACTORY FUNCTIONING, BEFORE SERVICING MACHINE OR REQUESTING
ASSISTANCE, CARRY OUT THE FOLLOWING CHECK:
- Check that when general switch is ON the relative lamp is ON. If this is not the case then the
problem is located on the mains (cables, plugs, outlets, fuses, etc.)
- There is no alarm signalling intervention of the thermostat safeguard, over or undervoltage
or short-circuit.
- Check that the nominal intermittance ratio is correct. In case there is a thermal protection
interruption, wait for the machine to cool down, check that the fan is working properly.
- Check the mains voltage: if the value is too high or too low the welding machine will be
stopped.
). This
- Check that there is no short-circuit at the output of the machine: if this is the case eliminate
the incovenience.
- Check that all connections of the welding circuit are correct, particularly that the work clamp
is well attached to the workpiece, with no interferring material or surface-coverings (ie.
Paint).
- Protective gas must be of appropriate type and quantity.
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