TIG Welding Equipment Unit 215 – Welding by TIG Process

Welding Equipment Types of welding sets Transformer/rectifier –a transformer reduces volts and increases amperages –transformers only work on alternating current (AC) supplies. –rectifiers convert AC current into direct current (DC) supplies –transformers are heavy and generate a lot of heat. Inverters –Inverters are high speed electronic switches –transformers are still needed but are much smaller –Inverter technology has seen smaller, lighter sets available for the welding industry –Inverter machines are more energy efficient that traditional transformer/inverter sets.

Welding Equipment Engine driven generators do not require a mains supply to operate generator driven by a diesel or petrol engine ideal for site work can provide electrical source for grinders etc.

TIG Welding Torch TIG torches come in different sizes to suit the welding machine output. They need to be light and flexible. They can be either air cooled or water cooled TIG torches are generally connected to the negative pole. Pencil torch

Torch Parts Back cap Collet Collet holder Tungsten electrodes Ceramic shroud

TIG Electrodes TIG electrodes are an alloy of tungsten and other elements. Additional elements improve arc initiation and stability They are available in a range of diameters: 1.6mm, 2.4mm, 3.2mm being the most common Tungsten electrodes are identified by the coloured tip. DescriptionAlloyTip colourUse Pure Tungsten100% tungstenGreenAC only Thoriated2% thoriumRedSteel Zirconiated0.8% zirconiumWhiteAluminium Ceriated2% ceriumGreyAll metals Lanthanated1.5% lanthanumGoldAll metals Thorium is radioactive and care needs to be taken when sharpening. A risk assessment is required.

Welding Leads Water out (not on air cooled) Harness Torch body Combined water in and power cable (not on air cooled) Shielding gas supply.

Other Connections Electricity needs to be a circuit to operate. To complete the circuit in welding a current return is connected to the workpiece. Current return clamps are rated to match the amperage of the welding set.

TIG Filler Wire Filler wire is selected to suit the material being welded. It is available in a range of diameters: 1mm, 1.6mm, 2.4mm, 3.3mm Steel filler wire is normally copper coated to prevent rusting. Filler wire should be segregated in storage to prevent incorrect selection. They should be stored in a warm, dry room to prevent corrosion.

Grinders and Sanders Grinders and sanders remove metal by abrasion. Grinding machines come in different sizes and are identified by the disc diameter that can be fitted. Gloves, overalls and eye protection must be used when using these machines. Beware of the direction of the sparks to protect others nearby. Sparks are hot, make sure no flammables are near.

Linishers Continuous sanding belt machines.