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ACA-384
Unitor ACA-384 is a DC electrode for gouging by the air-arc method. In this process, the arc is used to melt the metal, and the molten metal is then blown away by a jet of compressed air. This method has several advantages – it can be used for cutting stainless steel and other materials which are difficult to cut with an oxyacetylene torch. Most of those who have had some welding or cutting experience should be able to master the gouging technique by practising 2 or 3 times a day for about a week. A typical application of the air-arc method is the removal of sections which have been welded to the deck for securing deck cargo (flushing). Hold the electrode holder so that the electrode slopes back from the direction of travel. The air blast is directed along the rear of the electrode towards the arc. The depth and contour of the groove is controlled by the electrode angle and speed of travel. It is possible to cut grooves with a depth of up to 25 mm. A combination of wide electrode angle and slow speed of travel will produce a narrow, deep groove. The width of the groove will usually be about 3 mm wider than the electrode diameter. An electrode angle of approx. 35° will provide a normal groove depth and highest speed of travel. An electrode angle of 45–70° is used to obtain the deepest groove. Adjust the speed of travel to obtain an even, hissing sound and clean, smooth groove surface. The amount of metal which can be removed increases with increasing current. However, every electrode has an ideal current level which is slightly below its maximum. If the ideal level is exceeded, the welder will notice a considerable increase in electrode consumption.
When air-arc gouging with 8 mm electrodes and using 100 m cable, the cable size should be minimum 95 mm2.
WARNING!
Wet or damp air-carbon-arc electrodes will give off splinters and are dangerous in use. Damp electrodes must be dried out in a drying oven at 180 °C (356 °F) for 10 hours before use. The fumes from air-carbon-arc electrodes are dangerous and must not be inhaled. Arrange for suitable ventilation or use an air mask. Use approved ear protectors when working with air-arc electrodes and protect your body and head against molten metal spray.
3.01
The electrode held at a narrow angle to the groove (approx. 35°)
The position of the electrode when gouging in the overhead position
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