Page 200 - CITS - Welder - Trade Practical

WELDER - CITS

- 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

Perform Tee joint on M.S. plate (10 mm thick plate) in flat position
by GMAW

Objectives: At the end of this exercise you shall be able to
• perform Tee joint on M.S. plate (10 mm thick plate) in flat position by GMAW.

- Cut the plate by using hacksaw cutting as per drawing.
- Clean the joining edges and surface of the plates.
- Set the plate B on the plate A in the form of tee as per drawing.
- Tack weld on both ends of the tee joint

- Keep the tack welded job in the channel at 45 degrees from the horizontal plane so that the welding can be
done in flat/down hand position.
- Connect the torch to positive terminal of the machine.

- Weld the root run of the joint by using 1.mm dia. Mild steel filler wire and using stringer bead welding technique.
- Set 90 to 100 amps current/ corresponding wire feed rate 19 to 20 Arc and deposit the root run.
- 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.
- Deposit the 2nd run using stringer bead as shown in (Fig 1) covering the bottom plate A and 2/3 of the width
of the root run. parameters under techniques used for the root run.

- Clean the second run by wire brush.
Note: Avoid side-to-side movement of the electrode.

Deslag and clean the root bead thoroughly.
Deposit the final covering run with a 160 amp current.
Give side-to-side movement to the electrode not more than 2.5 times its dia.
Use the same electrode angle as was used for the root bead.

Note: Prevent the upper edge of the plate from melting off by not allowing the arc to concentrate
more on the upper edge.

Remove the slag with a chipping hammer.
Clean the weld with a steel wire brush.
Inspect the lap fillet weld and ensure. (Fig 2)

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CITS : C G & M - Welder - Exercise 50(B)