Page 178 - CITS - Fitter Trade Pactical - Volume - 2

FITTER - CITS

• Chip the slag from the bead, brush and inspect.

Use tongs to hold the hot job, chipping hammer and wire brush for chipping and cleaning, goggles
for the protection of the eyes.
• Clean the back side of the first bead thoroughly and grind tacks flush.

• Deposit the second bead on this side, using the same settings.
• Chip the slag from the bead, brush and inspect for faults.
• Practice this exercise until you can produce a sound butt weld.
While but joint welding 1/3rd of gap to be maintained according to the thickness of plate or flat section of
metal.

TASK 2 : T’ Fillet joint in flat position by arc welding
• Check the size of the raw material
• Mark and file to size

• Set and tack the job-pieces at both ends as ‘T’ fillet joint . (Refer to drawing).
• Ensure that a Ø 3.15mm electrode and a 130 amps current are used. Safety apparel should be worn.
• Clean the tacks, check alignment and reset the job, if necessary.

• Place the joint on a welding table in a flat position. (Tack side down - Refer skill sequence)
• Select a Ø 4mm M.S. electrode and set a 150-160 amps current.
• Deposit the first bead along the joint line with a correct and uniform
- Arc length
- Travel speed

- Electrode angle.
Ensure the electrode angle is 45° with the corner and 70° to 80° with the welding line in the direction
of travel.

Clean the weldment and inspect for faults.
• Clean the other side of the joint and grind the tacks flush.
• Set the joint in a flat position (weld side down).
• Make a second weld along the joint line with the same setting and technique as used for the first bead.

Clean the weld and inspect for the following weld characteristics.
- Smooth and close ripple appearance. Uniform width and height equal leg lengths
- Good fusion at the toe of the weld without undercut and overlap
- Leg length of the fillet weld equal to the plate thickness
• Repeat the exercise until you can produce good welds.

TASK 3 : Square butt joint in flat position by gas welding
• Check the size of the raw material.
• Mark and file to size.
• Set the job pieces on a welding table to form a square butt joint (open) with a root cap 1.5 mm.

• Set a gas welding plant, attach nozzles No.5 and set a pressure of 0.15kg/cm2 for both the gases.

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CITS : C G & M - Fitter - Exercise 51