Welding methods
Hot gas (hand) welding: for welding in the detail
With a hot air gun, welding rod and a speed welding nozzle you can weld linings, details and repairs where machines cannot reach.
See all welding methods in the overview
The method
Hot gas welding (hand welding) heats the base material and the welding rod with a hot air gun. The rod is pressed into the heated seam and fuses with the base material.
With a speed welding nozzle the rod is fed automatically and evenly, giving faster and more consistent seams. The method is used for linings, geomembranes, tarpaulins, details around fittings and repairs.
Technique determines quality
Hold the gun at a constant distance and angle and follow the seam at an even speed. Too slow burns the material; too fast leaves cold zones. The angle between rod and seam must also stay constant.
Always clean the seam, and match the rod material to the base material. Practise on offcuts and cut a test weld through to check that the joint is sound along its full length.
Where the method fits
Hot gas welding complements extrusion welding: the extruder for long, thick seams, hot gas for details, joints around fittings and small repairs. Many plastics welders carry both in the toolbox.
Checklist: start-up and inspection
Linings, details and repairs with hot gas and welding wire.
Before startup
- The wire material matches the base material, and the wire diameter fits the joint.
- The nozzle is clean and adapted to the joint geometry.
- The temperature is checked, and the seam is clean and dry.
- For PVC-U: extraction is connected and operational.
First weld seam (test)
- Test weld on scrap shows complete bonding between wire and base material.
- The wire is not burnt or stretched during welding.
During welding
- Constant distance, angle and speed along the entire weld seam.
- The rod is fed evenly and pressed gently into the heated groove.
After the weld
- The weld seam is visually inspected, and rod ends are secured.
- The work is documented with material, date and operator.