Welding technology is crucial to manufacturing; good welding techniques are essential for producing top-notch industrial products. Welding skills are familiar to any welder, but have you ever seen these specific techniques?
1. Maintain a wire rod extension of 1/4 to 3/8 inch (the length of the wire extending from the welding torch tip). 2. Use small-diameter wire when welding thin plates; use large-diameter wire and a high-current welding machine when welding thick plates. See the welding machine's specifications for detailed information.
MIG welding 1. Maintain a wire rod extension of 1/4 to 3/8 inch (the length of the wire extending from the welding torch tip).
2. Use small-diameter welding wire when welding thin plates; use large-diameter welding wire and a high-current welding machine when welding thick plates. See the welding machine's specifications for details.
3. Use the correct welding wire to weld the workpiece. Stainless steel welding wire is used for welding stainless steel, aluminum welding wire is used for welding aluminum, and steel welding wire is used for welding steel.
4. Use the correct shielding gas. Carbon dioxide is excellent for welding steel, but it may cause excessive heat when welding thin sheets. A mixture of 75% argon and 25% carbon dioxide should be used for welding thinner materials. For welding aluminum, only argon can be used. When welding steel, you can also use a mixture of all three gases (helium + argon + carbon dioxide).
5. To achieve optimal control of the weld bead, the welding wire should be kept directly aligned with the joint edge of the molten pool.
6. When welding is performed in an abnormal position (vertical welding, horizontal welding, overhead welding), a smaller molten pool should be maintained to achieve optimal control of the weld bead, and the smallest diameter welding wire should be used whenever possible.
7. Ensure that the size of the welding wire you are using matches the welding nozzle, bushing, and drive roller.
8. Regularly clean the welding torch liner and drive rollers to prevent spatter from the torch nozzle. Replace the torch if it becomes clogged or the wire feed is uneven.
9. Keep the welding torch as straight as possible during welding to avoid wire feeding problems.
10. Use both hands simultaneously during welding to ensure the welding torch is stable, and do so whenever possible. (This also applies to shielded metal arc welding, TIG welding, and plasma cutting.)
11. Adjust the tension of the wire feeder's wire spool and drive roller to just enough for wire feeding, not too tight.
12. When not in use, store the welding wire in a clean and dry place to avoid contamination that could affect the welding results.
13. Use a DC-EP power supply with reverse polarity.
14. The dragging (pulling) welding torch technique can achieve deeper penetration and narrower welds. The pushing torch technique can achieve shallower penetration and wider welds.
Aluminum welding: 1. The best welding torch for aluminum is a wire-drawing torch. If you cannot use this type of torch, use the shortest torch possible to keep it straight; only argon gas can be used as the shielding gas; and only the push-pull technique can be used when welding aluminum.
2. If you encounter wire feeding problems, you can try using a contact tip that is one size larger than the welding wire.
3. The most commonly used welding wire for welding aluminum is the softer standard welding wire. Another type is harder (easier to feed), and it is mainly used in welding operations that require higher hardness and strength.
4. Before welding begins, the oxide layer on the surface of the aluminum material must be removed using a special stainless steel brush.
5. Fill the crater properly after welding to prevent cracking. One way to do this is to leave the welding torch in the molten pool for a few seconds after welding.
Self-shielded flux-cored wire welding: 1. Use the pull (or drag) torch technique during welding.
2. Keep the welding wire clean and dry to achieve the best welding results.
3. This type of welding is similar to shielded metal arc welding because the slag layer on the weld surface must be thoroughly cleaned after welding. A slag hammer and wire brush can be used for slag removal.
4. Self-shielded flux-cored welding wire does not require a separate shielding gas container (the shielding agent is inside the welding wire). This feature makes it ideal for outdoor operations, as the shielding gas is easily dispersed outdoors.
5. Self-shielded flux-cored welding wire is more difficult than MIG welding when welding thin plates.
TIG welding is ideal for welding thin plates – the clean welding process produces a beautiful weld appearance.
2. Argon is used as a protective gas when welding steel and aluminum.
3. Use DC positive polarity (DCEN) for welding steel and stainless steel, and AC polarity for welding aluminum.
4. The push torch technique has always been used in TIG welding.
5. Match the size of the tungsten electrode to the size of the electrode fitting.
6. Welding aluminum materials – Pure tungsten electrodes should be used. This allows the tungsten to easily form a spherical tip during AC welding.
7. Welding steel and stainless steel – Tungsten electrodes containing 2% thorium should be used. When welding with DC positive electrodes, the tungsten electrodes should be sharpened.
1. Most of the time, the dragging torch technique is used in shielded metal arc welding.
2. Take precautions to prevent welding slag spatter.
3. Keep the welding rods clean and dry – follow the manufacturer’s recommendations.
4. Penetration: Negative DC - maximum penetration, AC - medium penetration (may also result in more splashing), positive DC - minimum penetration.
Resistance welding is not suitable for welding aluminum, copper, or copper alloys. It is only used for welding steel and stainless steel.
2. To obtain greater heat (current output), a shorter electrode arm should be used.
3. If the welding machine does not have heat control, the length of the electrode arm should be used for control. For example, a longer electrode arm should be used when welding thin plates that require low heat.
4. Be aware that longer electrode arms may bend, and you may also lose pressure applied to the weld.
5. Ensure there are no gaps between the workpieces being welded, otherwise the welding effect will be greatly affected.
6. Keep the two electrode arms aligned so that the electrodes are aligned with each other. Also, maintain appropriate pressure; do not apply too much or too little pressure.
7. If you need a good appearance on a certain side of the workpiece after welding, you can grind (with a machine) the side with the electrode.
8. Clean the electrodes frequently, otherwise the output (current) will decrease. Appropriate protective covers should also be placed on the electrodes.
