Spiral Conduit (Conduit / Split Loom)
Spiral conduit is a flexible plastic tube that wraps the cable bundle. It provides mechanical protection against chafing, stone impact, UV and sharp edges; the split type can be fitted over an existing bundle afterwards. It is not waterproof, so the sealing job remains with the gland and its seal.
The cable bundle on a vehicle or machine works in an environment that is constantly moving, hot and full of sharp edges. Conduit places a sacrificial layer between that environment and the cable jacket.
- Split type: it can be fitted over an existing bundle afterwards and service is easy; but unless it is rotated so the split faces downward, water and dust get in easily.
- Closed type: it is better at mechanical protection, and the cable has to be threaded through it during installation.
- End regions: where the conduit ends, the edge can cut the cable; finish the ends with sleeving or tape.
- Heat: near exhaust and hydraulic lines a heat-resistant type or a thermal sleeve is needed.
A common mistake with conduit is gathering the whole bundle into one thick conduit. This both brings power and signal lines side by side and lowers ampacity by increasing the number of loaded cores. Carry the power and signal bundles in separate conduits, on separate routes.
Context in which this term is used: Installation, redundancy and field continuity