Page 263 - CITS - Welder - Trade Practical

WELDER - CITS

EXERCISE 64: Construct Lap joint on MS sheet 1.6 mm in

Vertical position by GTAW.

Objectives

At the end of this exercise you shall be able to
• produce molten pool of required size by the manipulation of torch
• add filler metal at the required rate and place by manipulation the filler rod
• deposit fusion run with filler rod in flat position and maintain uniform arc travel speed
• clean and inspect the deposited beads for surface defects.

Job Sequence

• Cut the plate by using hacksaw cutting as per drawing
• Set the sheets and tack weld in the form of a “Square butt” joint on the welding in flat position
• Fill the crater
• Manipulate the torch and filler rod in the correct position with respect job

• Stop the weld at the left-hand edge of the joint after filling up in the crater at the end of the weld
• The angular distortion between the vertical and horizontal sheets of the Tee joint is automatically controlled
• The current set is 10 to 15 ampere
• At the end of the welding perform the carter filler treatment by repeating the torch switch ON-OFF

• Cut the arc and hold at the finishing point unit molten metal solidifies
• Visual inspection: slight convexity ,uniform width ,uniform ripples And free from under cut at the toes of the
weld indicate a smooth

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