Teknologi Las Kapal Aplication TIG Welding Proper Techniques and Procedures

Teknologi dan Rekayasa Introduction  TIG welding is considered highly artistic. The fine detail and quality of the welds produced depend on the artist.  However TIG welding is used to weld mild steel, aluminum, and stainless steel.

Teknologi dan Rekayasa What is Tig Welding? Tig Welding (tungsten inert gas) uses  a tungsten electrode that heats the metal you are welding  an argon gas which protects the weld pool from airborne contaminants  a filler metal, when required is added by hand

Teknologi dan Rekayasa Why use Tig Welding? Weld more metals than any other process Create high quality, clean welds – No sparks or spatter – No flux or slag – No smoke or fumes Use one shielding gas for all applications Weld in all positions

Teknologi dan Rekayasa TIG Welding Advantages  Offers greater operator control than competing procedures  Stronger, higher quality welds  Attractive “stitched” finish  No “smoke and spatter”  Some welds require no filler material (edge, butt and corner joints)  Highly resistant to cracking (ductile) and corrosion over long time periods

Teknologi dan Rekayasa TIG Welding Disadvantages  Many consider this the most difficult of all the popular welding processes  Torches often require a cooling system (such as water cooled torches, Amps)  Requires venting of shielding gas and particulate matter  Slower travel speeds Lower filler metal deposit rate Requires more hand eye coordination Brighter UV rays Equipment costs can be higher

Teknologi dan Rekayasa TIG Welding Components  Constant-current welding power supply  Non-Consumable Tungsten Electrode  Inert Shielding Gas – Usually argon or helium or a mixture  Optional Filler Rod

Teknologi dan Rekayasa TIG Welding Torch Ceramic Tip Back Cap Tungsten Rod

Teknologi dan Rekayasa TIG Machines Foot Control torch Ground Regulator Argon 100%

Teknologi dan Rekayasa Foot Control  Practice controlling the heat with the foot pedal to see the weld puddle increase and decrease. Ideally, you want your weld puddle to be about 1/4 inch wide. Keep your puddle size consistent so it doesn't grow, shrink, spread or narrow while you are welding.

Teknologi dan Rekayasa TIG Welding Specifics  Plasma consisting of ionized gases and metal vapors  Commonly used to weld thin sections of stainless steel, nickel and copper alloys, as well as light metals such as aluminum, magnesium, titanium

Teknologi dan Rekayasa TIG Welding Safety  Intense ultraviolet radiation requires special eye protection (welding helmet) and complete skin coverage to avoid sunburn  Requires ventilation of gases to avoid asphyxiation or inhalation of dangerous fumes  Be aware of fire hazard

Teknologi dan Rekayasa Tungsten Types  2% Thoriated Tungsten - AWS Class EWTh-2 RED Generally used for DC negative or straight polarity applications, this is the most common type of electrode used today. Provides excellent resistance from weld pool contamination, easier arc starting capabilities and a more stable arc. Contains 2% weight of thorium oxide (ThO2). Most common metals used for include: Carbon and Stainless Steel, Nickel Alloys, and Titanium.  Pure Tungsten - AWS Class EWP GREEN Used for AC welding applications. Ball the end to provide good arc stability. Typically the least expensive tungsten, but is more susceptible to weld contamination than thoriated, ceriated or lanthanated. Contains a minimum of 99.5% weight tungsten with no other alloys. Most common metals used for include: Aluminum and Magnesium Alloys (AC).

Teknologi dan Rekayasa Tungsten Types  2% Ceriated Tungsten - AWS Class EWCe-2 Orange Used for AC or DC welding applications. An excellent alternative to Thoriated tungsten especially in low amperage welding. Takes approximately 10% less current to initiate arc and has a very stable arc. Not a radioactive material and tends to last longer than thoriated. Contains 2% weight of Cerium Oxide (CeO2). Most common metals used for include: Carbon and Stainless Steels, Nickel Alloys and Titanium.

Teknologi dan Rekayasa Tungsten Types  1% Zirconiated Tungsten - AWS Class EWZr-1 Brown Used for AC welding applications. Better start up than pure tungsten, balls up well and has a more stable arc. Better current carrying capacity and high resistance to contamination during welding.  2% Lanthanated Tungsten - AWS Class EWLa-2 Blue Also called "rare earth" tungsten. Used for AC or DC welding applications. Characteristics are similar to ceriated, and is also non-radioactive. Contains 2% Lanthanum Oxide (LaO3). Most common metals used for include: Carbon and Stainless Steels, Nickel Alloys and Titanium.

Teknologi dan Rekayasa Tungsten Rod Preparation

Teknologi dan Rekayasa Tungsten Rod Preparation

Teknologi dan Rekayasa Proper Clothing  Long sleeve Shirt no frayed edges  Cotton pants with no frayed edges  Welding Gloves  Close toe shoes  Welding Helmet Not Automatic Shield  Preferably 10 or higher due to bright arch

Teknologi dan Rekayasa Remember Personal Safety 1) Wear safety glasses 2) Wear an approved shaded welding helmet 3) Wear insulated gloves 4) Wear durable clothes without pockets and folds 5) Wear shoes or boots that will provide protection to your feet

Teknologi dan Rekayasa How do I set up the Tig Welder? 1. Connect Torch 2. Connect Gas Hose and Regulator to Argon Cylinder 3. Connect Amperage Foot Pedal 4. Connect Work Clamp to the Work Piece 5. Prepare the Tungsten 6. Assemble the Torch 7. Install the Tungsten

Teknologi dan Rekayasa Before I Tig Weld 1. The tungsten should never touch the work piece, or it will be contaminated 2. The tungsten tip should be ground down to keep arc from wanderinp g 3. The argon flow pressure should be set to 30 psi 4. Choose the correct polarity for the application 5. Always push the torch toward the filler metal

Teknologi dan Rekayasa Lets Get Started  Get dressed  Get a welding helmet and meet me at the set up station  I will demonstrate proper arc length, torch angle, and filler rod feeding  After shop-work, a quiz will be given over the parts of the welder

Teknologi dan Rekayasa Choosing Polarity

Teknologi dan Rekayasa Choosing Gas Flow Rate

Teknologi dan Rekayasa Choosing Curren Range

Teknologi dan Rekayasa TIG Welding Operation

Teknologi dan Rekayasa Torch and Filler Positioning

Teknologi dan Rekayasa Torch and Filler Positioning

Teknologi dan Rekayasa Torch and Filler Positioning

Teknologi dan Rekayasa Torch and Filler Positioning

Teknologi dan Rekayasa How to do TIG welding 1. Align your torch at the correct angle 2. Set the foot pedal to the correct amperage, so that you create a ¼” wide weld pool 3 Align your filler metal to the correct 3. angle 4. Heat an area of the joint’s surface 5. Dab the filler metal quickly 6. Push the torch forward enough to heat a new weld pool and cool the previous weld pool

Teknologi dan Rekayasa SHOW TIG welding

Teknologi dan Rekayasa Knowledge is the key to success