Plane repair and fabrication of structural components and hot temperature components like exhaust systems and ducting components often necessitates NADCAP approved welded. exothermic welding
A gasoline gas such as acetylene or hydrogen is combined in an exceedingly welding torch with oxygen to produce a flame with a heat of around 6, three hundred degrees F. (3, 482 degrees C). This fire can be used to melt the materials to be welded. A filler rod is melted into the mess of molten metal to strengthen the weld. When highly-reactive metals such as lightweight aluminum are gas welded, they need to be covered with débordement to exclude oxygen from the molten metal and maintain oxides from creating which would decrease the strength of the welds.
Shielded Metal Arc Welded (SMAW).
This approach is the most familiar and common type and is known in the trade as stay welding. A metal line rod coated with a welding flux is clamped in an electrode holder linked to the electric power supply with a heavy electrical cable. The metallic to be welded is also attached to the ability supply. The electrical electric power comes to the work at a minimal voltage and high current and may be either AC or DC, depending after the sort of welding being done. A great arc is struck between rod and the work and produces heat in excess of 10, 500? F, which melts both the material and the rod. As the débordement melts, it releases an inert gas which protects the molten puddle from oxygen in the air and prevents oxidation. The molten flux covers the weld and hardens to an airtight slag cover that protects the welds bead as it lowers. This slag must be chipped off to evaluate the weld.
Gas Metallic Arc Welding (GMAW).
This technique of welding was earlier known as called Metal Inert Gas (MIG) welding and is a noticable difference over stick welded because an uncoated cable electrode is fed into the torch and an inert gas such as argon, helium, or and also carbon dioxide flows out around the wire to protect the puddle from o2. The strength supply connects between the torch and the work, and the arc produces the strong temperature needed to melt the effort and the electrode. Low voltage highcurrent DC is employed almost exclusively with GMAW welded. GMAW can be used more for large-volume production work than for aircraft repair.
Gas Tungsten Arc Welding (GTAW).
This is the form of electric arc welded that fills almost all of the needs in aircraft maintenance. It is more commonly known as Tungsten Inert Gas (TIG) welding and by the trade titles of Heliarc or Heliweld. These trade names were derived from the simple fact that the inert gas formerly used was helium.
Alternatively than by using a consumable electrode such as is employed in both of the other two methods we have discussed, the electrode in TIG welding is a tungsten rod. (In prior procedures making use of this form of welding, a carbon electrode was used, but it has been replaced almost exclusively with tungsten. )
The 250+ amp arc between your electrode and the work melts the material at 5, 432 certifications F, and a filler rod is manually raised on into the molten mess. A stream of inert gas such as argon (ar) or helium flows away of the torch and envelopes the arc, thus protecting against the formation of oxides in the mess.