Lecturer’s Name : Muhd Nizam b. ZahariGroup/ Name:

Syaida Bt. Ab Manaf ( 55101214062 )- LO4-P2

Date:

27 / 5 / 2015

Title :

Labwork 3(c) Tungsten Inert Gas Welding

Theory/ Summary :

Tungsten Inert gas welding (TIG) also known as Gas Tungsten arc welding(GTAW) is an

arc welding process that uses a non-consumable tungsten electrode to produce the weld. The

weld area is protected from atmospheric contamination by an inert shielding gas (argon or

helium) and a filler metal is normally used.

TIG welding is most commonly used to weld thin sections of stainless steel and non-

ferrous metals such as aluminum, magnesium, and copper alloys. The process grants the operator

greater control over the weld than competing processes such as shielded metal arc welding and

metal arc welding (MIG), allowing for stronger, higher quality welds and also more clean

because there is no slag leave after welding. However, TIG is comparatively more complex and

difficult to master and it is significantly slower than other welding technique. Besides, welder is

also exposed to huge intensities of light.

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Lab Report: CLD 20502 Basic Engineering Workshop

Methodology :

1. Draw the equipment for Tungsten inert gas welding.

Result & Discussion:

1. Sketch the process for Tungsten inert gas welding

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- End product -

2. Explain the problems that you have during TIG welding process.

The problem that happened during TIG welding process is poor gas coverage leads to

contamination. Weld contamination can occur when shielding gas is not turned on, there is too

little or too much gas shielding or the gas is blown away. Others are welding aluminum in the

wrong polarity or adjusting balance which is can mix the oxide layer with the filler metal and also

weld graininess which is cause by welding too hot causing too much base metal dilution.

Besides, craters is also the problem which is causes by dropping the weld power and

removing filler rod too quickly. There also too much amperage on aluminum. It will easily can

potentially leads to burn-through. Lastly, the lack of fusion at a T-joint or a fillet weld can be

caused by a few factors such as improper fit-up, holding the torch too far away from the joint

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(increasing arc length) and also improperly feeding the filler rod.

Conclusion:

As the conclusion, to get an excellent TIG welding, all the problems during welding must

be solve wisely such as start welding once the puddle has a shiny appearance, always remove all

grease, oil, and moisture from the filler and base metal. Other than that, reducing arc length to

provide better directional control and to help increase penetration. It is important not to under-fill

the joint or weld too quickly. Besides, reducing amperage to prevent overheating plus slightly

increase travel speed or shorten the arc length.

Tutorial:

1. What is the advantage of TIG welding?

I) Welding is very clean and leaves no slag at all.

II) Heat and amperage are precisely controlled and changes using a foot mechanism

III) Uses less energy than other welding methods

IV) Can be done in any position

2. What is the limitation of TIG welding?

I) Requires high skill to master

II) Slow process

III) Welder is exposed to huge intensities of light

IV) More expensive compare to MIG welding

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3. What is the electrode used in TIG welding?

I) Tungsten electrode *

II) Cerium oxide *

III) Lanthanum oxide *

IV) Aluminium electrode*

* Based on it applications

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