pei-POINT INVERTER AS25-13K Wartungsanleitungen Seite 17

3.3 GETTING READY TO WELD
WELDING CYCLE: The welding cycle consists of three basic times:
Squeeze time: it is the interval of time between the start of the cycle and the moment the electrodes, under the force exerted
on them, come into contact with the piece to be welded.
Weld time: this is the time during which the welding current passes through the electrode contact area.
Holding time: this is the time during which the force of the electrodes is maintained after weld time has finished.
The welding cycle can be divided in different times; for a more detailed explanation of this please read the paragraph relative to the
welding control unit.
3.4 INFLUENCE OF THE VARIOUS PARAMETERS ON THE WELDING RESULT
Force on the electrodes: The greater the force is on the electrodes, the weaker contact resistance will be between the electrodes
and the sheets and the less risk there will be of melted material being squirted. However, the force on the electrodes is limited by
the welding machine's capacity. The greater the force is on the electrodes, the greater the current value will be to achieve welding.
Weld time : Welding can be achieved with different weld times:
Short weld time:
(less than 200ms)
Long weld time: (400-1000ms)
Medium weld time: (200-400ms)
Current
Welding current influences the strength of the spot as does weld time but the influence is much stronger.
3.5 CHECKING SPOT QUALITY
There are different ways to check the quality of a welding spot. The best way, for the strength test, is the separation test of the
welded parts. This test entails gripping the welded sample pieces in a clamp and opening them with a scalpel. Strength is good if,
after the sheets have been separated, there is a hole on one sheet and the melted core on the other sheet.
3.6 OPERATING GUIDE
Prior to welding:
Turn the welding machine on with the main switch (6)
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Check that the "set value" display turns on and that all the signalling lights are tested.
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Check on the gauge for compressed air.
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- Check that the set welding parameters are ideal for the piece you are welding and for electrode aperture (squeeze time).
Wear individual protection gear (gloves, glasses, aprons, etc.).
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Starting:
Gun: Press the red push button to bring the electrodes to the point to be welded.
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Once squeeze time has elapsed, current will start passing between the sheets, determining the welding
spot. Press black push button in order to clamp work piece without welding, if clamping position is
correct, it is possible to complete the weld sequence pressing red button. If an extra opening is needed to
reach difficult welding point, use the side yellow push button to achieve it.
Spotter: Use the gun's lever switch to spot weld.
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Stopping the cycle and emergency stopping:
The cycle can be stopped at any time, when you take your foot off the pedal.
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To stop in an emergency, turn the main switch off and discharge the pneumatic circuit through the dump valve.
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INVERTER AS25-13K AS25-15K "R3.2"
it effects a small area of material being heated but the welding machine's performance
is superior.
it leaves a heavy electrode mark on the sheets and utilises the machine to the utmost
a good compromise between the two extremes
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Resistance Welding Solutions