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==== ==== Norton Internet Security 2012, 3 Computers, 1 Year Subscription (PC) by Norton from Symantec http://tiny.cc/utry7 ==== ==== HOWTOWELD.CO.UK What is arc welding. Arc welding is a fusion welding process that utilizes a welding power supply (direct or alternating current) to generate a continuous electric arc between a coated metal electrode and the base weld material that heats to create coalescence and bonds the metals at the tip of the welding point. The electrode functions as a filler metal and the welding region may be protected by shielding gas or vapor or slag. Arc welding is also referred to as Shielded Metal Arc Welding (SMAW) or manual metal arc welding process or stick welding or electric arc welding. Fusion occurs due to the heat of the electric arc maintained between the end of the coated electrode and the work piece. This melts the base metal, the tip of the electrode rod, and also the coating. The metal drops are transferred into the molten weld area across the arc and is shielded from the external atmosphere by the flux gases. Solidification of the weld metal starts with the molten slag protective coating on top. Types of Arc Welding: Arc welding, the most common kinds of welding has different forms, such as Flux, MIG or stick welding. * Shielded metal arc welding (SMAW), the most simple, oldest, prevalent and versatile type of Arc Welding that uses concentrated heat of an electric arc to joins metals. * Flux-cored arc welding (FCAW) that uses tubular electrodes filled with flux. * Gas metal arc welding (GMAW), or MIG welding that shields the welding arc with a inert gas; useful for thin sheets. * Gas tungsten arc welding (GTAW) or TIG welding that uses tungsten electrodes and inert gases. * Plasma arc welding (PAW) uses ionized gases and electrodes to generate extremely hot plasma jets. * Submerged arc welding (SAW) that has a granular flux fed into the weld zone to form a thick layer. What do you need? Arc Welding is popular because of the simplicity of the equipment needed. It can be done professionally or as a garage hobby too with minimal equipment. Equipments needed: 1. Welding power unit and Electrical Current. Both DC and AC current is used depending on the electrode. 2. Electrode holder and electrode or the welding stick. 3. Heavy duty metal ground clamps 4. Welding cables and connectors. 5. Accessory equipment (chipping hammer, wire brush)


6. Protective equipment (welding mask, fireproof clothing, helmet, gloves, fire extinguisher, etc.)

How to Arc Weld 1) Set up your work area and make sure the work piece is clean before the welding starts. Ground the base metal with the metal clamp attached to the arc welding unit to create a steady electrical current loop necessary for the welding. 2) Plug in the electrode or welding stick into the electrode holder. This forms the other end of the electrical current loop. 3) Set the required amps and voltage on the welder based on the size of the electrode and the thickness of the base metal. 4) Use correct length of electrodes and optimum arc distance based on experience. Welding current begins to flow as soon as the metals strike each other. To start, gently tap or scrap the electrode on the metal. 5) Steadily move the electrode with an eye on the weld puddle till the weld joint is complete. Move the electrode along the work piece at correct speed to deposit metal in a uniform layer called the bead. Generally welding is done on flat or horizontal position. If vertical or overhead welding is required, the amps has to be reduced. Best results are achieved with short welding arcs and uniform speed. 6) Once solidification is complete, remove the slag coating with a chipping hammer or wire brush. Advantages and Disadvantages of Arc Welding: Advantages * Versatile - can be used for a variety of applications with a wide range of electrodes. * Simple, portable equipment, and used for a long time. * Lower costs of equipment and process * Can be done in small garages and confined spaces and even remote locations * Out-of-position welding is possible Disadvantages * Other latest processes like continuous wire processes are more productive * Slower due to Frequent stop and starts to change electrodes * Relatively high metal wastage from electrode stubs and high costs for depositing low metal welds The power in the welding unit is measured in terms of voltage and current. The voltage or Volts is based on the arc length and electrode diameter. Current is measured in amperes (Amps), and the Amps needed depends on the electrode diameter, and the size and thickness of the work pieces, the and also the position of the welding. Thick metals require more Amps than thin sheets, and small electrodes require less Amps than the large ones. Arc welding is popular at construction sites, offshore oil rigs, and in most repair shops. It's quite


easy pick it up as a hobby, but it will be a while to master it skillfully. HOWTOWELD.CO.UK ==== ==== Norton Internet Security 2012, 3 Computers, 1 Year Subscription (PC) by Norton from Symantec http://tiny.cc/utry7 ==== ====

how to arc weld | what is arc welding  
how to arc weld | what is arc welding  

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