CHEMICAL WELDING. •••••••••••••••••••••••••••• A. Chemical Welding :- Acetone is used for absorbing C2H2 and storing in cylinders at high pressure. Cast iron is best welded by using gas welding with neutral or slightly Oxidizing flame. If acetone comes out and participate in reaction colour of flame will be purple for complete combustion of mole of C2H2, 2.5 moles of oxygen is required. B. Types of Flame :- * Neutral Flame - For this flame use both the gases in the ratio of 1:1 by volume. This flame is used for welding of cast iron, mild steel, low carbon steel, Aluminium. (C2H2 = O2) Outer blue flame → 1275°C. Inner white core → 3100° C. * Carburizing Flame - For this flame excess fuel gas (C2H2) is used. It is used for welding medium carbon steel, nickel etc. (C2H2> O2). Intermediate flame → 2900°C. * Oxidizing Flame - For this type of flame excess oxygen (O2) is used. This type of flame is used for welding oxygen free copper (Cu) alloys, brass, bronze and zinc base materials. (C2H2
Posted on: Mon, 01 Sep 2014 15:47:34 +0000
Trending Topics
Recently Viewed Topics
© 2015