Page 215 - CITS - Welder - Trade Practical

WELDER - CITS

EXERCISE 53 : Make single ‘V’ butt joint on M.S. (10mm.

thick plate) in horizontal position by GMAW

Objectives

At the end of this exercise you shall be able to
• set the plate as a Tee joint in Horizontal position
• deposit the root run using 0.8mm diameter Co2 filler wire to get a root penetration and fusion
• deposit the 2nd and 3rd run using the stringer bead technique and maintain an equal leg length of 8mm
• avoid overlap on the bottom plate and undercut on the vertical plate
• maintain a good contour and weld reinforcement of 1.5 to 2.0mm.

Job Sequence

• Prepare the plates to size (i.e 150 x 50 x 10mm) using gas cutting, grinding and filing.
• Clean the base metal surface along the welding line with a carbon steel wire brush.
• Set the plates in the form of an inverted “T”.
• Wear all protective devices.

• Tack weld the 2 plates on either end keeping the T joint in Horizontal position.
• Set the welding parameters as done in earlier exercises.
• Strike the arc keeping proper angles for the torch.
• Deposit the root run without weaving and ensure proper penetration and fill the crater.

• Clean the root run.
• Deposit the 2nd run using stringer bead.
• Clean the 2nd run with wire brush.
• Deposit the 3rd run using stringer bead.
• Clean the 3rd run.

• Check for defects like overlap, undercut, porosity and check for corret leg size and throat thickness.

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