Page 294 - CITS - Welder - Trade Practical

WELDER - CITS

EXERCISE 75: Make Square butt joint on Tube welding on
M.S. tube metals in rolled position by GTAW

Objectives

At the end of this exercise you shall be able to
• prepare plate pieces by gas cutting and by grinding to size
• set plates as a lap joint and tack weld at both ends
• place the lap joint in a flat position for welding
• deposit root run of proper size and ensure penetration
• deposit the final covering run in the lap joint of proper leg size
• clean and inspect the lap fillet weld for surface defects.

Job Sequence

- Welding is a fabrication process that joins materials
- usually metals or thermoplastics, by using high heat to melt the parts together and allowing them to cool,
causing fusion
- Welding is distinct from lower temperature techniques such as brazing and soldering, which do not melt the
base metal (parent metal).

- In addition to melting the base metal, a filler material is typically added to the joint to form a pool of molten
material (the weld pool) that cools to form a joint that, based on weld configuration (butt, full penetration, fillet,
etc.),

- can be stronger than the base material Pressure may also be used in conjunction with heat or by itself to
produce a weld.
- lding also requires a form of shield to protect the filler metals or melted metals from being contaminated or
oxidized

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CITS : C G & M - Welder - Exercise 74