Following proper procedures can make drawn arc welding aluminum an efficient and straightforward process, however the quality of welding results can still be affected by many variables.
Aluminum differs from its alloys in having narrower tolerances for set up and welding parameters, necessitating careful preparation and cleaning of the workpiece prior to welding.
Drawn Arc Welding
Northland Fastening Systems can equip you with all of the tools, studs and expertise you need to effectively weld aluminum surfaces using various stud welding methods. Aluminum has a lower melting point than most metals but using effective processes can produce strong welds that stand up under harsh environments and critical applications.
Drawn arc welding is an efficient solution for most applications. The method uses a drawn stud with a collar to eliminate punching, drilling or tapping from one side only – ideal for tamper proof applications requiring single point welds from only one side of an object. Furthermore, drawn arc welding reduces manufacturing costs by eliminating pre-grinding or recoating processes, and can even be applied on painted surfaces.
A stud gun is activated and produces an arc with a pilot arc to lift and melt studs to set heights before returning pressure forges them together to produce stronger welds than their surrounding material.
Shielding gas is essential when welding aluminum using drawn arc welding techniques, to protect workers from toxic fumes that may contaminate the weld zone and keep toxic fumes out of workers’ lungs. A mixture of argon and helium (Ar/He) is recommended, due to He’s superior arc ionization energy than pure Ar, leading to greater thermal conductivity at the weld zone.
Shielding Gas
Shielding gas used in stud welding has an immense influence on weld quality. It can alter how the arc behaves, whether slag-free welds are produced and their overall aesthetic. Furthermore, it affects how quickly aluminum melts down as well as strength of joints created.
Choose the ideal shielding gas for each project carefully, as various types of aluminum require specific shielding gases, while copper- and nickel-based alloys require different ones as well. Pure argon works best as it’s inert while for ferrous metals like steel and cast iron an oxidizing blend might be better suited.
Another factor affecting weld quality is the type of welding gun. Some stud welding guns utilize capacitor discharge (CD) technology; in this system, a capacitor charges up to its preset power source setting before “discharging,” creating an electric burst that vaporizes stud tips while simultaneously creating a molten pool on base metal and stud that the spring of gun pushes down into.
CD welding methods offer many advantages for aluminum stud applications, such as shorter arc duration and lower heat generation. However, high plunging speeds can result in cold plunges which reduce load-bearing capabilities of welds; to prevent this happening it is essential that thorough surface preparation as well as adjustments are made accordingly to accommodate various weld and framework conditions before beginning welding operations.
Welding Parameters
Aluminum studs are used in numerous manufacturing applications. Within the food industry, they can be welded into tabletops or counters to avoid contamination from loose components and provide an attractive yet clean appearance – ideal in catering settings where hygiene is of utmost importance.
To ensure the quality of welds, aluminum surfaces must be thoroughly prepared before welding. Oxides may accumulate on them and impede with the weld process; for optimal surface preparation, brush off oxides before wiping down with non-VOC cleaner.
Recommended Weld Time for CD and Drawn Arc Studs | CMC Group Ltd. For optimal results, it is advised that weld times be kept under 10 milliseconds. A shorter weld time will help limit unwanted conduction of heat away from the weld point and help limit unwanted heat conduction away from it.
Polarization of welds should also be carefully considered. Aluminum is more conductive than steel and therefore needs to be positively polarized in order for welds to penetrate deeper into its sheet metal and build their full strength.
Cleaning
Stud welding is an efficient and economical means of attaching threaded or unthreaded metal fasteners to various base metals and substrates, including threaded or unthreaded fasteners that have threads. Stud welding has many applications across industries including manufacturing, construction, mining and more – from assembly lines to medical facilities stud welding can help increase productivity while decreasing costs.
This stud welding method allows manufacturers to speed up production for larger and more complex products by eliminating tedious hand-welding processes, creating stronger connections that withstand everyday stress without corrosion issues.
Stud welding can also be used to attach essential equipment, like refrigeration units and food processing machines, securely to buildings or vehicles, creating an airtight seal against contaminants and pathogens entering. Furthermore, this form of welding can be employed underground to secure sewer pipes or electrical conduits against leakage or structural failure that could potentially present hazardous situations.
To achieve optimal results from drawn arc stud welding, it is crucial that the work piece be properly prepared prior to welding. This includes stripping away any coatings not appropriate for welding such as paint, rust or grease and leaving only clean and metallically bright surfaces for welding – this is particularly important with aluminum which quickly forms an oxide surface layer which prevents good welds.