Page 71 - CITS - Welder - Trade Theory

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