Page 71 - CITS - Welder - Trade Theory
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WELDER - CITS




                  Fig 2












                  Fig 3










           Uses: Useful for stylizing (hard facing),‘Lined ’welding of steel pipes, and flame cleaning.

           These lection of the flame is based on the metal to be welded
           The neutral flame is the most commonly used flame. (See the chart given below.)
           Metal Flame
           Mild steel  Neutral

           Copper (de- oxidized) Neutral
           Brass  Oxidizing
           Cast iron  Neutral
           Stain less steel Neutral
           Aluminum (Pure) Neutral
           Satellite Carburizing


           Production of calcium carbide
           Objectives : At the end of this lesson you shall be able to
           •   state the ingredients and grades of calcium carbide
           •   describe the properties of calcium carbide
           •   explain the method of production of calcium carbide
           •   explain the safe storage and handling of calcium carbide.


           Introduction
           Calcium  carbide  is  a  chemical  compound  consisting  of  calcium  62.5  %    and  carbon  37.5  %    by  weight.  Its
           chemical symbol is cac2
           Properties of Calcium Carbide
           1  It is a solid chemical compound of dark grey colour.
           2  It  is brittle.

           3  Its density it 2.22 to 2.26 gmlc.c.
           4  It easily absorbs moisture from the atmosphere and gradually changes into slaked line.
           5  It is not soluble in kerosene.




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                                            CITS : C G & M - Welder - Lesson 14-26                                                                              CITS : C G & M - Welder - Lesson 14-26
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