1. The most suitable for welding aluminum is the wire-type welding torch. If you can not use this welding torch, try to use the shortest welding torch to keep the welding torch straight; only use argon as shielding gas; in welding aluminum (automatic pipe welding) Only when using the gun method.
2. If you find a wire feed problem, try a conductive head that is one size larger than the wire.
3. The most commonly used wire for welding aluminum is a softer standard wire. The other is harder (easier to feed the wire), which is mainly used in welding operations where hardness and strength are required.
4. Before the welding starts, the aluminum oxide layer should be removed. Use a special stainless steel brush to remove the oxide layer.
5. Fill the crater at the end of the weld to prevent cracks. One way is to leave the torch in the bath for a few seconds after soldering.
Aspect 02 Aluminum profile welding precautions
1. Welding of aluminum
Welding characteristics: aluminum and aluminum alloy have strong thermal conductivity, large heat capacity, large coefficient of linear expansion, low melting point and low temperature strength. The welding is difficult, and certain measures should be taken to ensure the welding quality.
Pipe and wire cleaning, the surface of the wire and the 50mm sides of the wire are cleaned with acetone, and the surface oxide film is removed by brush with stainless steel to expose the metal luster. The cleaned hole must be welded within 2 hours. The wire is placed in an unused cylinder and must be used within 8 hours, otherwise it will be reprocessed.
The tungsten rod is made of tantalum tungsten rod, the argon gas is not less than 99.96%, and the water content should not be more than 50mg/m3.
The ambient temperature should not be lower than 5 °C, otherwise it should be preheated to 100~200 °C before welding, relative humidity control.
2. Required equipment
You need to have at least a $4,000 welder and superb welding techniques to weld the aluminum; you can do a good job without the need for practice; you need to buy an expensive torch that is suitable for aluminum welding.
3. Successfully welded aluminum
The fact is that a compact small MIG welder can also perform temporary aluminum welding operations after training, using the right welding equipment and performing the correct parameter settings. You will be able to use the MIG welder to complete the welding of various materials in your home, such as grills, backyard storage rooms, docks, and even decorative parts. Even home welding enthusiasts who often weld steel will feel that welding aluminum is a great challenge. The reason is: the aluminum wire is very soft and the wire feeding is quite difficult. In addition, the wire diameter and welder settings typically used for steel may not be suitable for welding aluminum.
Aspect 03 To successfully weld aluminum, understand the following questions
1. What kind of equipment do I need?
The first decision you need to make is what kind of equipment you need to achieve your goals. Keep in mind that the 115 volt wire feeder is capable of handling 22 to 12 gauge welds and you may be able to weld 1/8 inch thick material with proper preheating. But be careful, the maximum preheating is limited to 250 degrees Fahrenheit. The other is a 230 volt machine that can weld materials from size 22 up to 3/16 inch. Proper warm-up can increase the range to 1/4 inch. If you need to weld plates of various thicknesses, consider a 230 volt welder.
Remember, if you are going to do very regular aluminum machining, you will need a heavy-duty welder. The 115 and 230 volt compact MIG welders can be used for occasional aluminum welding, but it is not recommended to use them for complex and heavy aluminum welding, otherwise welding equipment exceeding 200 amps should be considered. After you have determined the input voltage, the other question you usually ask when choosing a welder is, do I need a continuous voltage regulation model or a tapped coil model? The continuous voltage regulation model allows you to steplessly adjust the set voltage within the machine's voltage limits, making it more adaptable, allowing for more efficient adjustment and precise control. This allows you to adjust more easily during welding operations.
2. What kind of protective gas?
The shielding gas required for MIG welding of aluminum and welded steel is different. For welding aluminum, 100% argon should be chosen. However, steel welding requires mixed gas or 100% carbon dioxide gas. The good news is that we don't need any special equipment - your existing regulators (except carbon dioxide regulators) and the air tubes can be used in pure or mixed gases.
3. What kind of polarity is set?
All MIG welding, including aluminum welding, requires a positive electrode, while the core welding process is typically a negative electrode. If you want to switch the welder in a different process, first determine the polarity of the switch. This is a mistake that novices usually make.
4. What kind of aluminum alloy electrode should I buy?
If you try to use steel electrodes when welding aluminum, you will get very bad results. Instead, we recommend that the compact MIG welder use a 4043 aluminum alloy filler metal that is limited to 0.035 inch diameter. The 5336 aluminum alloy electrode may be recommended to retailers and distributors because it is harder and easier to wire.
However, with this wire feeder, the 5356 aluminum alloy usually has insufficient current to achieve a good welding effect. Although the 4030 is relatively soft, better wire feed performance can be achieved by following the appropriate steps described below. Do not use welding wires of other diameters. In particular, avoid 0.030 inch wire (very difficult to wire feed) and 3/64 inch wire (the compact small welder does not provide enough current to reliably melt the wire of this diameter).
5. How do I set up my welder to weld aluminum?
Since you know the type and performance/limitation of the welder, the next very important step is how to set the parameters. Follow the tips below: Buy a set of aluminum wire feeding tools; pay attention to the wire feeding when welding aluminum It is even more important, so it is highly recommended to purchase a special set of aluminum wire feeding tools. The set of tools will contain the following items:
Non-metallic liner - designed to minimize delivery
Wire Friction 2. U-groove drive roller - used to prevent the soft aluminum wire from breaking or deforming. These drive rollers do not scratch the aluminum wire like the V-groove roller. If the V-groove roller is used, the wire scraping liner will be blocked and the wire feeding failure will occur.
Import and export guides - designed to avoid wire scratches
Contact Head - The contact used in the welding of aluminum has a larger diameter opening because it produces more expansion than steel when the aluminum wire heats up. Therefore, the size of the aluminum wire-specific contact head is small enough to allow electrical expansion while being sufficiently large to allow expansion.
Loading wire to welder
There is a trick to properly insert the aluminum wire. (The same applies to steel wire) It is very important to load the aluminum wire and avoid the failure during welding. Hold the wire shaft securely with one hand to ensure that it does not loosen. Once you have removed the cellophane package, hold the loose one of the wire with the other hand - do not put it in the drive roller let go. People who are inexperienced usually do not grip the loose one, and the entire bundle of wires begins to loosen. If such a thing happens, it will not be remedied, and the welding operation will be greatly affected - you have to buy another bundle of welding wire.
Set the tightness of the wire brake
The tightness only needs to ensure that the welding wire will not just loosen, but it should not be too tight, otherwise it will cause drag on the welding wire.
To set it up correctly, first tighten the tightness, then install the wire and let it pass the drive roller. If the roller is moving except the wire, and the other parts are stopped, it is not tight enough. Be careful when handling, as too much tension will cause too much force on the wire. In addition, do not be nervous when the last few turns of the wire are not fed; usually because the wire is too hard to be loose.
Set the driving roller tightness
This is probably the most important step in the entire setup process. Experts recommend placing the wire at a slight angle 1 inch from the surface of the insulation. Then, set the roller tightness to a minimum. Press the switch on the torch to observe its operation - it should slide when the wire touches the surface of the insulation. From that point on, tighten the tightness until the wire stops sliding.
Again, be aware that too tight will cause the wire to break. This means that the welding wire stays in the welding torch, and the wire driving roller is still rotating. The final result is that the wire breaks after running out of the roller, or the back pressure causes the welding wire to become a mess, including the guiding liner, the welding gun liner and the like. Keep in mind that when you set the wheel tightness as described above, press the torch switch and the wire is hot, so always wear good quality welding gloves.
Ensure a good power connection
In the first step, the fixture for welding should be securely clamped in areas where the workpiece is not painted and contaminated. To clean the workpiece, use a degreasing solvent to remove all grease. Also ensure that the surface of the workpiece is dry before welding. Also, do not weld in the presence of flammable materials, such as solvents or paint containers. In the second step, the surface oxide of the aluminum is cleaned with a clean stainless steel wire brush.
Positioning is very important
When soldering, try to keep the torch cable straight to minimize wire feed constraints on softer aluminum wire. Bending of the torch cable can cause the wire to knot, resulting in poor wire feed.