Which temperature figure actually counts?
Datasheets often quote three values: continuous, short-term and peak. Always calculate with the continuous figure, since that applies over the material's life. A conduit rated 'short-term 300 °C' may have a continuous limit of 105 °C — with a furnace radiating all day, that 300 °C is irrelevant.
How do you tackle radiant heat?
Radiation is not removed by insulating the cable more thickly; you must shield it. An aluminium-laminated mat at 20 to 50 mm distance reflects most of it and lets air circulate in between. Insulation applied directly on the cable traps heat and raises the core temperature.
What works against weld spatter and glowing particles?
A glass-fibre weave with silicone or vermiculite coating: the particle scorches the outer layer but does not penetrate. Plastic corrugated conduits are unsuitable here; a spatter melts straight through and the cable is next. For robot welding we combine a spatter-resistant sleeve with an aluminium shield along the path.
How does heat change current rating?
Every cable has a derating table: at 60 °C ambient you may carry roughly 70% of nominal current, at 80 °C around 50%. Insulating protection lowers those figures further because heat cannot escape. So always check derating alongside the material choice.
| Heat source | Solution | Continuous | Short-term |
|---|---|---|---|
| Warme hal 50–70 °C | PUR-slang / mantel | 90 °C | 125 °C |
| Oven, straling | Reflecterende mat | 260 °C | 500 °C |
| Lasspatten | Glasvezel + siliconen | 260 °C | 1000 °C kort |
| Hete spanen | Stalen ketting / afdekking | 250 °C | 600 °C |
Frequently asked questions
- Can a plastic cable carrier be used at a welding robot?
- Only with shielding. Directly in the spatter zone choose steel or a plastic chain with a spatter-resistant cover; otherwise a spatter burns into the side band and weakens it locally.
- How much distance should a reflective mat keep?
- Allow a 20 to 50 mm air gap between mat and cable. Without a gap the mat conducts heat through; with a gap the air layer acts as extra insulation.
- Can you assess the thermal load for me?
- Yes. Send a photo of the setup, the measured ambient temperature and the type of heat source; we advise on material, shielding and, if needed, a larger conductor size.
Read next
- What do IP ratings mean for cable protection conduits?The two digits explained, plus why a conduit only achieves an IP rating together with its gland.
- Plastic or steel cable carrier: when do you choose which?Travel, fill weight, temperature, swarf and noise decide — with concrete thresholds per criterion.
- Which cable entry do you choose for pre-terminated cables?Split grommet, frame or snap entry: packing density, IP rating and strain relief compared.