Page 97 - CITS - Welder - Trade Theory

WELDER - CITS

Remedies - weld speed keep the correct, filler rod use correct thickness, set the correct flame. Use to correct
nozzle size.
3 Overlap - Metal flowing into the surface of the base metal without fusing it.
Causes - not correct to edges preparation. not a correct flame, weld joint not a clean, welding technique wrong.
Remedies - correct to edges preparation. use to correct flame, weld joint should be clean need.

4 Excessive penetration
Depth of fusion at the root of the groove joint is more then the required amount.
Causes - nozzle use too large size, flame keep the one place more time, nozzle angle not proper maintain.
Flame making the (velocity) large size, edge preparation not correct. Base metal gap also not correct
Remedies - nozzle use correct size flame, do not keep the one place more time, nozzle angle proper maintain
60 to 70 degree, flame making the (velocity) small size, edge preparation.

5 Lack of penetration / lack of fusion-
Required amount of penetration is not achieved. Fusion does not take place up to the, root of the weld. No melting
of the edges of the base metal at the root face.
Cause - Incorrect joint preparation and set up. Wrong edge preparation. Nozzle use very small size, Welding use
more speed, Flame use very small.
Remedies - Edge preparation correct need, and setup correct need, Nozzle use correct size .
Welding use correct speed, flame use correct - neutral flame.

6 Porosity - Number of pinhole on the surface of the deposit metal.
Blow Hole - These are similar to pin holes but have a greater diameter.
Causes - Use of incorrect/old filler rod and technique, Welding surface not proper clean.
Use the old stored fluxes, Not dry the job and filler wire and atmosphere. Effect of oxidization & hydrogen ,Entry
of Atmospheric contamination

Remedies - Use of correct filler rod and technique.
Welding surface proper clean.
Use the new fluxes

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CITS : C G & M - Welder - Lesson 14-26 CITS : C G & M - Welder - Lesson 14-26