1. Scope and purpose
This manual covers routine maintenance of water and air cooled TIG (Argon Arc Welding) torches used in industrial production. Following the procedures described in this document is critical to ensuring arc stability, weld quality, and preventing premature failure of torch components. Maintenance should be carried out as planned or when unstable arc operation is detected.
2. Safety measures
ATTENTION: Before starting work, be sure to perform the locking and tagging procedure (Lockout/Tagout). Turn off the power source of the welding machine and shut off the supply of shielding gas. Work only with appropriate personal protective equipment (PPE), including safety glasses, welding gloves, and fire safety clothing. Be careful with hot torch surfaces after welding is complete.
3. Necessary tools and materials
| The name of the tool | Specification | Quantity |
|---|
| Torque wrench | The range is 0.5 - 10 Nm | 1 |
| Digital multimeter | To measure resistance/integrity | 1 |
| Ultrasonic bath | With heating (optional) | 1 |
| Flowmeter (rotameter) | To check the shielding gas | 1 |
| Sharpening kit | Diamond disc (grit 120-200) | 1 |
| Coolant liquid | As per OEM specification | 1 |
| Clean napkins | Hairless | 5 |
4. Preliminary inspection before service
| Element | Verification | Eligibility criteria | Notes |
|---|
| Burner body | Visual inspection for cracks | No damage | Replace if there are cracks |
| Cables and hoses | Insulation integrity | Absence of bends and cuts | - |
| Electrode | Tip wear | No pollution | Sharpen or replace |
| Gas lens | Grid cleanliness | Absence of deposits | Clean or replace |
5. Step-by-step procedure
5.1. Preparation of tungsten electrode
- Remove the electrode from the collet.
- Set the sharpening angle (usually 30-60 degrees depending on the amperage). Avoid cross grinding - always grind along the axis of the electrode for arc stability.
- Sand the tip to a smooth surface.
- Install the electrode with a projection of 3-6 mm from the nozzle. Incorrect departure leads to arc instability.
5.2. Cleaning the gas lens
- Disassemble the front part of the burner (nozzle, gas lens).
- Inspect the gas lens grid for clogging with combustion products.
- Rinse in an ultrasonic bath with a suitable solvent for 5-10 minutes. Do not use aggressive acids that can damage the sealing rings.
- Dry with compressed air.
- Check the cleanliness of the holes - they should be freely passable.
5.3. Flushing the cooling system
- Disconnect the coolant supply and return hoses.
- Drain the old fluid into a container for disposal.
- Flush the system with distilled water (pressure no more than 2 bar).
- Check the tightness of all connections.
- Refill with fresh coolant per OEM specification.
- Check the flow (typically 0.5-1.5 l/min) using a flow meter. Weak flow leads to overheating and failure of the burner coil.
6. Post-service checklist
| Test | Expected result | Actual result | Status |
|---|
| System tightness | No leaks | - | Pass/Fail |
| Gas flow | Compliance with the given value | - | Pass/Fail |
| Arc stability | The arc burns stably | - | Pass/Fail |
7. Search and troubleshooting
| Symptom | Probable cause | action |
|---|
| Unstable arc | Contaminated electrode | Sharpen/replace the electrode |
| Burner overheating | Low coolant flow | Check the pump and hoses |
| Seam porosity | Clogging of the gas lens | Clean or replace the lens |
8. Recommended maintenance schedule
| Task | Frequency | Duration | Level |
|---|
| Electrode preparation | Each work cycle | 5 min | Technician |
| Cleaning the gas lens | Every week | 15 min | Technician |
| Flushing the cooling system | Every quarter | 60 min | Engineer |
9. Spare parts
| Description of the part | Typical specification | UNITEC-D category |
|---|
| Collet | 1.6mm / 2.4mm / 3.2mm | TIG-T01 |
| Gas Lens (Gas Lens) | Standard / Large | TIG-T02 |
| Ceramic nozzle | No. 6 - 12 | TIG-T03 |
| Tungsten electrode | WT20 (Thoriated) / E3 | TIG-T04 |
The complete list is available at https://www.unitecd.com/e-catalog/
10. Links
- ISO 14175: Welding materials. Shielding gases for arc welding.
- EN 60974-7: Equipment for arc welding. Burners.
- Equipment manufacturer's OEM instructions.
