Page 118 - CITS - Welder - Trade Practical

WELDER - CITS

EXERCISE 23 : Square butt joint on brass sheet 2mm

thick in flat position (OAW)

Objectives

At the end of this exercise you shall be able to
• remove oxides and other impurities from the surface of the base metal
• prepare a square edge and set the sheets as a butt joint
• select the correct size of nozzle and filler rod, gas pressure and flux
• set a soft oxidizing flame and tack-weld the butt joint
• manipulate the filler rod and blowpipe with appropriate angles and weld the joint
• clean and check the penetration and inspect the weld for weld defects.

Job Sequence

• Prepare the brass sheets as per dimension given in the sketch.
• Deburr the edges of the sheet.
• Clean the surfaces of the sheet and remove oxides if any.
• Select nozzle No. 5 and set 0.15 kg/cm2 pressure for both the gases.

• Select a silicon-bronze rod of 1.5 mm ø.
• Select brass flux (borax type). Apply the flux by dipping the hot end of the filler rod in the powdered flux from
time to time.

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