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Welder’s Handbook
Stick-out – The length of un-melted electrode extending beyond the end of the gas nozzle.
TIG (Tungsten Inert Gas) Welding – An arc welding process wherein coalescence is produced by heating with an arc between a single tungsten (non-consumable) electrode and the work Shielding is obtained from a gas or gas mixture. Pressure may or may not be used and filler metal may or may not be used. (Also called Gas Tungsten Arc Welding – GTAW)
Stringer Bead – A straight weld bead opposed to a weaving bead. In surfacing, the weaving bead produces less dilution because the weld puddle is always in contact with the part of the bead produced on the previous oscillation rather than the base metal. Stub – The short length of filler metal electrode, welding rod, or brazing rod that remains after its use for welding or brazing. Submerged Arc Welding – An arc welding process that uses an arc or arcs between a bare metal electrode or electrodes and the weld pool. The arc and molten metal are shielded by a blanket of granular flux on the workpieces. The process is used without pressure and with filler metal from the electrode and sometimes from a supplemental source (welding rod, flux, or metal granules). Swirl Baffle – It serves is a mounting platform for the nozzle, sets up a swirling direction of the gas through the small holes in the swirl baffle and carries the electrical current to the work piece. T Tack Weld – A weld made to hold the parts of a weldment in proper alignment until the final welds are made. Temper – (1) The amount of carbon present in the steel: 10 temper is 1.00% carbon. (2) The degree of hardness that an alloy has after heat treatment or cold working, via the aluminium alloys. This usually lowers the hardness and strength and increases the toughness of the steel.
Tip to Work Distance – The distance between the outer most portion of the contact tube or tip and the work surface.
Titania – The synthetic form of titanium dioxide (TiO2). In this text the terms rutile and titania have the same significance. T-Joint – A joint between two members located approximately at right angles to each other in the form of a T.
Toe – The point on the weld bead that meets the parent metal. Every weld bead has two “toes”.
Toe Crack – A crack originating at the junction between the face of the weld and the base metal It may be any one of three types: (1) radial or stress crack; (2) under-bead crack extending through the hardened zone below the fusion line; or (3) the result of poor fusion between the deposited filler metal and the base metal.
Torch to Work Distance – The distance between the outer most portion of the torch and the work surface.
Transferred Arc – A plasma arc established between the electrode of the plasma arc torch and the workpiece.
Transformation – The changes in the crystalline structure of metals caused by temperature and time.
Transformation Temperature – The temperature at which the crystal structure of the steel changes, usually about 1600°F.
Temper of Continuous Welding Electrodes – The stiffness or strength of the electrode.
Transformer – An electrical device used to raise or lower the voltage and inversely change the amperage.
Tensile Strength – The resistance of a material to a force which is acting to pull it apart.
Transition Temperature – The temperature at which the crystal structure of steel changes, usually in the range of 1500-1600°F.
Tension Test – A test in which a specimen is loaded in tension until failure occurs.
Thoriated Tungsten – A metal used as the plasma cutting electrode emitter for a non-oxidizing plasma gas such as nitrogen.
Transverse Crack – A crack with its major axis oriented approximately perpendicular to the weld axis.
Transverse Weld Test Specimen – A weld test specimen with its major axis perpendicular to the weld axis.
Throat – The cylindrical part of the orifice which controls the quantity of oxygen which is consumed.
Travel Angle – The angle less than 90 degrees between the electrode axis and a line perpendicular to the weld axis, in a plane determined by the electrode axis and the weld axis. This angle can also be used to partially define the position of guns, torches, rods, and beams.
Tight – References the removal of slag, tight means it does not release readily, and will require moderate chipping to remove.
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