Resistance Welding Electrodes Can Be Custom Made
Many types of materials are joined daily though out the world to make consumer items and machinery. A variety of processes are used to join two pieces of materials together. Here we discuss metal to metal and steel to steel welding.
Wire feed, Arc welding, TIG welding, Gas welding, and Spot welding are the most common types of welding methods used these days. Arc welding is also called as stick welding while gasless welding or flux covered or MIG and gas also are known as wire feed welding.
MIG welding is also called as Gas Metal Arc Welding. It is cost-effective but does not give you precision-based results. The welders have to hold a torch in their hand and squeeze a trigger to bring the wire out of the torch. The wire then heats up and welds the spot you want to weld.
The temperature of around 6,300 degrees F can be achieved when acetylene or hydrogen is mixed inside a welding torch with oxygen to make the flame that melts the two materials to be joined. Thermodes or filler rods are melted into the puddle of molten metal to support the weld. Aluminum has to be shielded with gas to exclude oxygen from the molten so oxides do not form as this can decrease the strength of the joint.
Arc welding is also known as MMAW or SMAW welding. Manual or shielded arc welding uses an electrode that is a foot long and is covered with flux. When the rod is used it burns off the flux and creates a gas that shields the weld. SMAW welding is a common way of welding two metal pieces is also known as stick welding. Heavy electric cables are used during the process and the stick is clamped in an electrode holder which is connected to the power supply. The metal you want to weld is also connected to the power supply so it can take a current. The current can be high or low voltage. Depending on the type of weld you need it could be either AC or DC.
The arc is struck between the work pieces and heat of more than 10,000°F is produced. As a result, the rod and the material both get melted. In the process, the gas is used to protect the site of the weld by keeping out the oxygen. Oxygen has an oxidation effect which is eliminated by the use of gas that is released from the flux when it melts. Molten flux creates an airtight slag which protects the joint. Welders need to chop off the slag to check the weld.
TIG, on the other hand, is a more delicate method. It requires more concentration and attention. The welder has to hold the torch in one hand and the filler in the other hand. The rod is slowly fed to the weld to make a stable joint. If you do not want to hold a filler rod in your hand you can do your welds using the TIG or Gas Tungsten Arc Welding (GTAW). It will melt two pieces of metal together with heat. The metals are fused by the heat that emanates from the arc.
In aircraft maintenance, GTAW is used. It is also called as TIG welding. In it, the original gas used for welding was helium. Most welding processes use consumable electrodes, but with TIG the tungsten rods are used which are not consumable. In this form of welding a 250+ amp arc is created between the electrode and the work pieces. This arc melts the metal at 5,432 degrees F while the filler rod is fed into the molten puddle. Inert gases such as argon or helium flow from the torch to shield the arc. This way oxidation is prevented in the puddle.
For sheet metal fabrication the best method of welding is the spot welding. It uses electrodes to make the weld. The two metals to be joined are placed in an ideal position and then pressure and heat are used o make the weld. It takes only a few seconds to join strong metal together using this technique. Spot welding, for this reason, is now more popular. Many manufacturers are making modern equipment to make the task of spot welding much easier. Users can control the temperature and the amount of pressure required to make a strong weld. The settings can be saved in the software and this way you can make hundreds of joints within a minute.
In the manufacture and repairs of cars and aircrafts spot welding is used. For aircraft repair, NADCAP approved welding processes are used. Welders have to be certified and qualified enough to do the job. These welders have to be certified in Torch / Induction braze, Fusion (GTAW) welding, Electron Beam welding or Resistance welding. The aerospace industry continues to work towards raising its standards and improving quality.
The best resistance welding electrodes are Tungsten and molybdenum. These can be bought in various shapes and sizes. Electrodes are used to transfer heat and apply pressure to work pieces. There are various types of thermodes available on the market to choose from. Electrodes can be made of various metals. The choice depends on the type of metal you want to join. You can also get a custom made electrode to meet your unique needs.