Material data & installation
Marshall-Tufflex cable management products are manufactured in Extra Super High Impact PVC-U grade material, capable of withstanding the most hazardous conditions on site.
PVC-U characteristics
| Specific gravity | 1.42 |
| Coefficient of thermal expansion | 7 × 10⁻⁵ / °C |
| Water absorption | Negligible |
| Fire performance — BS 476 Pt 6 & 7 | Class 1 |
| Fire performance — UL 94 | V-0 @ 1.6mm |
| Fire performance — BS EN 61386-1 / BS 4607 | Pass |
| Oxygen index | 42% |
| Tensile strength | 492 / 562 kg/cm² |
| Vicat softening point (conduit) | 80 °C — BS EN ISO 306 |
| Operating temperature | −5 °C to +60 °C |
| Thermal conductivity | 0.19 W/m/°C |
| Impact resistance | −5 °C heavy gauge requirement of BS EN 61386-1 |
Installation guidance
Fixing centres
Secure horizontal runs at a maximum of 0.9m and vertical runs at a maximum of 1.2m. Reduce these in high ambient temperature or where rapid temperature change is likely. At fittings and directional changes, secure approximately 150mm either side.
Expansion joints
Fit expansion couplers at a maximum of 6m. Solvent-cement the short side only; insert the next length approximately 50mm into the long side and do not glue — the conduit must remain free to move in the saddles.
Cold bending, 20–25mm
Use the correct size and gauge of bending spring — heavy gauge banded red, light gauge banded blue; springs are not interchangeable. Make the bend more acute than required to allow for recovery. In cold weather, warm the conduit before bending.
Earthing
The properties of PVC-U make it an all-insulated system — a separate earth cable is essential. Bend radii per BS 7671:2018 Section 522.8.3.
Storage & transport
Support conduit at not more than 1.0m centres, stack with sockets at alternate ends and protruding, heaviest at the bottom. Protect spigots and sockets from sharp edges; take extra care in cold weather.