Page 223 - CITS - Welder - Trade Practical

WELDER - CITS

- Set 70 to 90 amps current
- Ensure proper root penetration and even fusion of plate A and B with suitable welding gun / torch angle and
Arc travel speed
- Clean the root run using steel wire brush
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.

- Ensure the undercut in bottom plate is avoided and a leg length of plate thickness 10 mm is obtained.
- Clean the second run by wire brush
- Use tongs while handling the hot job
- Check the all connections before welding
- Welding area should be dry area

- Use welding screen and chipping goggle for eyes and face safety
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 lap fillet weld for surface defects and size.

Skill Sequence

Demonstrate fabrication of tee joint on m.s. plate (sheet 6 mm.
thick plate) in vertical downward progression by GMAW

Objectives: At the end of this exercise you shall be able to
• demonstrate fabrication of tee joint on m.s. plate (sheet 6 mm thick plate) in vertical downward progression by
GMAW.

1 Prepare the plates to size (i.e150x50x10 mm) using gas cutting, grinding and filing.
2 Clean the base metal surface along the welding line with a carbon steel wire brush.
3 Set the plates in the form of an inverted “T”.

4 Wear all protective devices.
5 Tack welds the 2 plates, keeping the T joint in horizontal position.
6 Set the welding parameters as done in earlier exercises.
7 Strike the arc keeping proper angles for the torch.

8 Deposit the root run without weaving and ensure proper penetration and fill the crater.
9 Clean the root run.
10 Depositthe2ndrun.
11 Clean the 2ndrun.

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CITS : C G & M - Welder - Exercise 54(B)