Page 229 - CITS - Welder - Trade Practical

WELDER - CITS

- Complete the joint using the bead sequence. Use as light weave to help the weld flow and to use to the side
walls of the groove and the previous beads
- When you have completed the weld, cool it and examine it. The root should show full penetration along the
entire length. The root reinforcement should protrude beyond the joint from 0.5 to 1mm. The face of the weld
should merge smoothly with the base metal. The reinforcement should be at least 1mm above the surface of
the base metal and also should not exceed beyond 1.5.
Note: Wear protective clothing.

• Tack-weld on both ends.
• Set the lap joint in a flat position.
• Deposit root run with 100-110 amps current.

Note: Ensure an electrode angle of 45° with the fillet corner and 80° with the welding line.
• Remove the slag with a chipping hammer and clean with a wire brush.
• Use tongs to hold the job.

• Wear chipping goggle for the protection of eyes.
• Deposit the final covering run with a weave motion with150-160amps welding current.

Note: Prevent the upper edge of the plate from melting off.
• Remove the slag from the final weld and clean thoroughly.

Note: Use a weld gauge to check the fillet size.
• Inspect the butt fillet weld for surface defects and size.

Skill Sequence

Make single V butt joint on M.S. (10 mm. thick plate) in
vertical position by GMAW

Objectives: At the end of this exercise you shall be able to
• make single v butt joint on m.s. (10 mm. thick plate) in vertical position by GMAW.

Setting and tacking the butt joint.

Set the butt joint with an overlap of 25mm.
The overlap may vary based on the plate thickness.
Tack-weld on both ends. Ensure the 2 surfaces are perfectly cleaned and they contact each other properly. with
120-amp current for tacking.

Set the joint in a vertical position using angle iron.
Note: Welding the lap fillet joint in flat position

Deposit root run with 100-110 amp current.
Maintain 80° angle to the line of the weld and 45° between the weld faces.
Maintain a short arc to get uniform fusion and root penetration.

Note: Avoid side-to-side movement of the electrode.
Deslag and clean the root bead thoroughly.

Deposit the final covering run with 160 amp current.

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CITS : C G & M - Welder - Exercise 55 CITS : C G & M - Welder - Exercise 55