MIG welding
01 Maintain 1/4-3/8 inch extension of the welding rod (the length of welding wire extending from the welding torch head).
02 Use small diameter welding wire when welding thin plates; Use large diameter welding wire and high current welding machine when welding thick plates.
03 Use the correct welding wire to weld the workpiece. Stainless steel wire welding stainless steel, aluminum wire welding aluminum, steel wire connecting steel.
04 Use the correct protective gas. Carbon dioxide is very suitable for welding steel, but the temperature may be too high when it is used to weld thin plates. The mixed gas of 75% argon and 25% carbon dioxide should be used to weld thin materials. Welding aluminum can only use argon gas. When welding steel, you can also use a mixture of three gases (helium+argon+carbon dioxide).
05 In order to achieve the best effect of controlling the weld bead, the welding wire should be kept directly aligned with the bonding edge of the weld pool.
06 When the welding operation is in an abnormal position (vertical welding, horizontal welding and overhead welding), the weld pool should be kept small to achieve the best control of the weld bead, and the welding wire with the smallest diameter should be used as much as possible.
07 Make sure that the size of the welding wire you use matches the bushing, bushing and driving roller.
08 Always clean the welding gun liner and drive roller to keep the gun muzzle free of splash. If the welding muzzle is blocked or the wire feeding is not smooth, replace it.
09 Try to keep the torch straight when welding to avoid wire feeding problems.
10 Use both hands at the same time during the welding operation to ensure the stability of the welding gun, and do so as much as possible. (This also applies to covered electrode welding, TIG welding and plasma cutting).
11 Adjust the tightness of welding wire reel and driving roller of wire feeder just enough to feed wire, not too tight.
12 When the welding wire is not in use, keep it in a clean and dry place to avoid pollution and affect the welding effect.
13 Dc reverse polarity DCEP power supply is used.
14 Deep penetration and narrow weld can be obtained by dragging (pulling) welding torch technique. Pushing gun technique can obtain shallow penetration and wide weld.
Aluminum welding
01 The most suitable welding torch for welding aluminum is wire drawing welding torch. If you can’t use this kind of welding torch, try to use the shortest welding torch to keep the welding torch straight. Only argon can be used as protective gas; Only the shotguns method can be used when welding aluminum.
02 If you find that there is a wire feeding problem, you can try a conductive head with a size larger than the welding wire.
03 The most commonly used welding wire for welding aluminum is the soft standard welding wire. The other is harder (easier to feed wire), and it is mainly used in welding operations with higher hardness and strength requirements.
04 Before welding, the oxide layer on the aluminum surface should be removed, and a special stainless steel brush should be used to remove the oxide layer.
05 Fill the arc pit at the end of welding to prevent cracks. One way is to leave the torch in the molten pool for a few seconds after welding.
Self-shielded flux-cored wire welding
01 Use the drawing (or dragging) gun technique when welding.
02 Keep the welding wire clean and dry to achieve the best welding effect.
03 This kind of welding is similar to covered electrode welding, because the slag layer on the weld surface after welding must be cleaned up after welding. Slag hammer and wire brush can be used for slag removal.
04 Self-shielded flux-cored wire welding does not need redundant protective gas container. (The protective agent is inside the welding wire). This feature makes it very suitable for outdoor operation, because the protective gas used outdoors is easy to be blown away.
05 Self-shielded flux-cored wire welding is more difficult than MIG welding in welding thin plates.
TIG Welding
01 Very suitable for thin plate welding-a clean welding process can obtain a beautiful welding appearance.
02 Argon is used as shielding gas when welding steel and aluminum.
03 Direct current positive polarity (DCEN) is used to weld steel and stainless steel, and alternating current is used to weld aluminum.
04 Push gun technique has been used in TIG welding.
05 Match the size of the tungsten electrode with the size of the sleeve nozzle.
06 Welding aluminum-pure tungsten electrode should be used. In this way, tungsten can easily form a spherical tip during AC welding.
07 Welding steel and stainless steel-Tungsten electrode containing 2% thorium shall be used. The tungsten electrode should be sharpened during DC positive electrode welding.
Covered electrode arc welding
01 Most of the time, the gun-dragging technique is used.
02 Be prepared to prevent welding slag from splashing.
03 Keep covered electrode clean and dry-follow the manufacturer’s recommendations.
04 Penetration: negative direct current-maximum penetration, alternating current-medium penetration (or more splash), positive direct current-minimum penetration.
Resistance welding
01 Resistance welding is not suitable for welding aluminum, copper or copper alloys. But only for welding steel and stainless steel.
02 To get more heat (current output), shorter electrode arms should be used.
03 If it is a welding machine without heat control function, it should be controlled by the length of the electrode arm. For example, a long electrode arm is used when welding thin plates that require low heat.
04 Note that the longer electrode arm may bend, and you may also lose the pressure on the weld.
05 Make sure there is no gap between welding workpieces, otherwise the welding effect will be greatly affected.
06 Keep the two electrode arms aligned so that the electrodes are aligned with each other. Also, keep adjusting the appropriate pressure, not too big or too small.
07 If you need one side of the workpiece to have a good appearance after welding, you can grind (use a machine) the electrode side.
08 Clean the electrodes frequently, otherwise the output (current) will decrease. Appropriate protective covers should also be put on the electrodes.
