Torch brazing uses a flame to melt filler metal and join metal parts, without melting the base metals. It can be used for repair work and manufacturing, and is cost-effective and portable. Automatic torch brazing is used for lap joints.
Torch brazing is one of the most versatile brazing processes and is used in a variety of industrial applications. Using air or oxygen in combination with flammable gases, such as propane or acetylene, torch brazing uses the heat from a flame to melt a filler metal to join two or more metal parts. This type of brazing can be used to join two pieces of metal with different properties because the process only melts the filler metal and does not melt the base metals. While torch brazing can be used for manufacturing processes, it is most commonly associated with repair work.
In acetylene or propane torch brazing, the metals used must be protected from the flux – an agent that removes oxidation from metals – or a vacuum chamber, unless the metal oxidizes in the temperature range required for the brazing process. The direct flame from the brazing torch is applied to the metal and pre-set filler metal in a heating process that heats the base metals and the flux. The filler metal, which may be a copper-zinc alloy, a silver-based alloy, or an aluminum-silicon alloy, is melted by the heat and capillary action causes the filler metal to flow between the two pieces to join. After cooling, the filler metal acts as an adhesive between the joined pieces, permanently bonding them together.
The most common method of torch brazing is hand torch brazing. This method is widely used because the equipment is easily portable and relatively low in cost compared to other welding methods. Requiring a relatively small setup of hoses and gauges, along with a torch and two portable tanks, this method requires less gas and creates less heat stress on metal parts than traditional welding, but it’s not appropriate for every situation. Torch brazing is useful for light work as it can be used to make proper, watertight repairs quickly. It is not a recommended repair method for projects that require the ability to withstand high amounts of mechanical stress.
In manufacturing situations, automatic torch brazing is sometimes used to seal lap joints. In this process, the product is assembled with pieces of filler metal and flux strategically placed in the joints. The entire product is then heated as it passes through the various workstations, melting the filler metal and causing it to flow into the joints and bond the metal parts together. The result is a cleanly welded joint with a uniform appearance and a watertight bond.
Protect your devices with Threat Protection by NordVPN
