Page 161 - CITS - Welder - Trade Practical

WELDER - CITS

Job Sequence

• Keep the template firmly on the vertical and horizontal pipes
• Mark the pipe by using a template.

• Mark and punch it.
• Cut the marked pipe with an oxy-acetylene cutting blowpipe or a hand hacksaw.
• Grind the cutting edges and set for tack-welding the pipe Tee joint with the 1.6 mm root gap.
• Round off the cutting edges.
• Set and tack weld the 90 pipe Tee joint with the 1.6 mm root gap and in correct alignment by using a try square.

Deposition of weld beads
• Divide the pipe welding into 4 segments and mark them 1, 2, 3, and 4.
• Start the root run with a 3.15 mm electrode and use 130 amps current. Complete the welding on side number
1. Then start on side number 2 and complete it. Then start on side number 3 and complete it. Finally start on
side number 4 and complete. This will minimize distortion.
• Use the keyhole method and keep the welding electrode position slightly uphill so as to obtain uniform
penetration.
• After cleaning the root run, weld the final run with a 3.15 mm o electrode and use 130 amps current.
• Complete the welds with slight sideways movement of the electrode and clean it with a chipping hammer and
wire brush.
Inspect the welds
• Check root penetration, undercut, reinforcement height and bead appearance.

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CITS : C G & M - Welder - Exercise 34 CITS : C G & M - Welder - Exercise 34