Page 115 - CITS - Welder - Trade Practical
P. 115
WELDER - CITS
EXERCISE 22 : Square butt joint on copper sheet 2mm
thick in flat position (1 G)
Objectives
At the end of this exercise you shall be able to
• select correct nozzle size and filler rod (composition and size), gas pressures and flux
• apply flux on the joint and filler rod
• preheat and post heat the job
• manipulate the blowpipe and filler rod in an appropriate way during welding
• clean the joint and remove any flux residue
• check the weldment for surface defects and bead size, profile.
Job Sequence
1 Remove the oxides from the surfaces of the deoxidised copper sheet.
2 Clean the joint from other impurities using solvent/ pickling.
3 If pickling/solvent is used for cleaning, then thoroughly wash and dry the joint before tack welding.
4 Prepare square edges of the pieces by filing.
Note : Do not use grinding to prepare the edges of non-ferrous metals.
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