Page 58 - CITS - Welder - Trade Practical

WELDER - CITS

• Excessive metal deposition at the bottom of the plate.
• Deslag and clean the root run.
• Deposit the second and third run using stringer bead technique covering the previously laid bead partially and
the plate surface.
• Ensure to fill the crater and to clean the bead.
• Check for the size of fillet, bead profile, weld defects and rectify them.

Skill Sequence

Fillet weld lap joint MS plate 10mm horizontal position

Objectives: At the end of this exercise you shall be able to
• prepare and weld lap joint on MS plate 10mm in horizontal position

Fix the joint in a horizontal position. For this the bottom plate should be kept parallel to the ground and the other
plate perpendicular.
Welding Lap joint (fillet) in horizontal position: Deposit root run with 3.15 mm dia. Electrode and 110 amps welding
current, maintaining the electrode angle 70° to 80° to the line of weld and 40° to 50° between the vertical plate
and electrode.
Deslag and clean the root bead thoroughly. Use safety

Goggles while deslagging to protect the eyes from
Flying slag particles.
Deposit second run with a 4mm electrode and 160 amps welding current, the angle of electrode to the bottom
plate to be 55° - 65° and 25° - 35° to the vertical plate and 70° to 80° to the line of weld.

This second run has to be deposited partly covering the root run and partly on the bottom plate.
Give a steady movement to the electrode using a short arc.
Deslag and clean the weld bead.
Deposit the third and final run with a 4 mm dia. Electrode and 160 amps welding current. Angle of the electrode
to the line of weld is 70° to 80° and 40° - 50° on both plates. The third run has to be deposited in such a way that
the bead covers partly the root run and the second run and partly the vertical plate. Also, there should not be a
valley at the bottom toe line of the third run in order to maintain necessary throat thickness. If two pass technique
is adopted second run should be done in a weaving motion.

Deslag and clean the weld bead.
Note: Avoid over-deposition and side undercut by using a proper angle and travel speed of the
electrode.

Inspection of Tee joint
Inspect the fillet weld for equal leg length and correct size.
Inspect to ensure the fillet weld is free from undercut and excessive lapping on bottom plate.

Fillet - ‘T’ joint on MS plate 10mm thick in horizontal

position (SMAW)

Objectives: At the end of this exercise you shall be able to
• select electrode, current, polarity and arc length
• use distortion control and arc blow control methods
• weld the ‘T’ joint with a short arc and uniform travel speed
• inspect the weldments for external defects.

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CITS : C G & M - Welder - Exercise 8