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Showing posts from November, 2015

Lathe Operations: Facing

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Facing Operations Facing is the process of removing metal from the end of a workpiece to produce a flat surface. Most often, the workpiece is cylindrical, but using a 4-jaw chuck you can face rectangular or odd-shaped work to form cubes and other non-cylindrical shapes.

When a lathe cutting tool removes metal it applies considerable tangential (i.e. lateral or sideways) force to the workpiece. To safely perform a facing operation the end of the workpiece must be positioned close to the jaws of the chuck. The workpiece should not extend more than 2-3 times its diameter from the chuck jaws unless a steady rest is used to support the free end. Cutting Speeds

If you read many books on machining you will find a lot of information about the correct cutting speed for the movement of the cutting tool in relation to the workpiece. You must consider the rotational speed of the workpiece and the movement of the tool relative to the workpiece. Basically, the softer the metal the faster the cutting. D…

Brief details about 'Advanced Welding Process'

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While welding with oxy-acetylene or arc welding the welder faces main difficulty of oxidation. To avoid oxidation fluxes are used but fluxes are also corrosive in nature that’s why these welding process (oxy-Acetylene and electric arc) can’t be used on A/C equipment. For A/C equipment advanced welding techniques are used. These techniques are TIG, MIG, EBW, etc.

Gas Tungsten Arc Welding (GTAW)
Gas tungsten arc welding uses the heat of an electric arc between a tungsten electrode and the base metal. A Separate welding filler rod is fed into the molten base metal, if needed. A shielding gas flows around the arc to keep away air and other harmful materials. This process is called as TIG (Tungsten Inert Gas) welding.
Gas tungsten arc welding is particularly desirable when welding stainless steel, aluminum, titanium, and many other nonferrous metals.
Figure "Gas Tungsten Arc Welding Plant" illustrates a typical station for gas tungsten arc welding. An AC-DC welding machine may be…