Aluminum Foil Textile Sleeve — Radiant Heat
A three-layer construction for harness runs that pass near radiant heat: aluminum foil outer face, textile carrier underneath, crimp-formed into a tube. The foil reflects radiation away from the bundle; the textile carries the flex so the foil does not work-harden and crack; the crimp gives the laminate a fixed tubular shape that bends with the route. Slip-on, non-shrink, silver finish. Sized on the largest object the sleeve must pass: usually a connector, not the cable.
Specification
| Material | Aluminum foil + textile substrate (crimped laminate) |
|---|---|
| Shrink behavior | Non-shrink slip-on sleeve |
| Function | Radiant heat reflection + mechanical protection |
| Color | Silver |
The layers and what each one does
- Outer foil face. The working surface. Bright aluminum reflects the majority of radiant energy that reaches it, which is why orientation matters more here than on any other sleeve type. The foil is also the first abrasion sacrificial layer.
- Textile carrier. A foil tube alone cracks the first time it bends. The textile backing takes the bending strain, spacing and supporting the foil so the reflective face survives route curves and harness flex.
- Crimp / tube forming. The laminate is crimp-formed into a fixed-diameter tube. Unlike a braided sleeve it does not expand during install : sizing must be done on the largest object passing through, and the fixed form is what keeps the foil face smoothly oriented instead of wrinkling.
- Closure / seam. The tube's longitudinal joint is a crimp seam. It is a functional joint, not a bonded weld; treat it as the line to keep clear of clamps and, where possible, out of the direct radiant face.
Three functions — only two are claimed
Radiant heat reflection : claimed. This is the product's purpose: a reflective metal face standing between the radiation source and the bundle.
Mechanical protection : claimed. The laminate and textile carrier add scuff and cut-through resistance over the covered run.
Electrical insulation : not claimed. The foil is conductive. This sleeve is not a dielectric layer, and where circuits need isolation the wire insulation does that job. If a conductive facing is unwanted near live parts, say so at RFQ and we will propose a non-conductive alternative.
Routing and installation inputs
- Bundle / harness OD and largest object. Size on connectors, splices and boots : the sleeve does not stretch over them.
- Route and bends. The crimped tube bends with the harness but on a larger radius than braid; check it clears on tight elbows without kinking the laminate.
- Seam orientation. Keep the crimp seam off the clamping lines and, where the design allows, off the direct radiant face.
- Foil inspection. After routing, check the foil face : especially at connector crossings and clamp edges. Patch or replace heat-side damage before service.
- Abrasion points. Where the run passes a metal edge, add an edge guard or clamp liner; the foil is sacrificial but not inexhaustible.
- Distance from heat source. Reflection drops sharply with distance from the source. Tell us the distance and the source type (exhaust manifold, turbo, heater) and we confirm suitability of this build : and where it is not enough, the fiberglass step-up.
Common failure modes, and prevention
Reflection lost after install
Cause: Sleeve fitted foil-side in, or rotated in service so the textile faces the source.
Prevention: Orient the foil face at the source, secure both ends against rotation, and check orientation again after any harness rework.
Foil cracked along a bend
Cause: Route radius tighter than the laminate accepts, or the sleeve was pulled around a corner under tension.
Prevention: Follow the harness's own bend radius, relieve tension at corners, and where the route forces a tight bend, split the run into two sleeve sections with an intermediate tie.
Sleeve scuffed through at clamp edges
Cause: Hard clamp edges working on the foil under vibration.
Prevention: Use lined clamps or a tie with a broad bearing surface; position clamps over the textile-backed portion, not on the seam.
Sized on cable OD, will not pass the connector
Cause: The crimped tube does not expand; the ID was chosen from cable OD alone.
Prevention: Measure the largest object on the run and size to that with working clearance. If the connector dwarfs the cable, consider a two-piece install with the sleeve threaded before termination on that segment.
Frequently asked questions
Which side should face the heat source?
The aluminum foil face. Reflection is a surface effect: radiant energy is reflected by the bright metal surface, so the foil must be the outermost layer oriented toward the radiation source. If the sleeve is installed foil-side in, the textile layer sees the radiation and the reflective function is gone. The assembly is left with only the mechanical protection. On runs where the heat source sits on one side, orient the seam and the foil face accordingly and secure the sleeve so it cannot rotate in service.
What happens if the foil layer is torn or creased?
A torn or deeply creased foil area stops reflecting where the metal is cracked or missing. That patch of the bundle falls back on whatever the textile carrier and any underlying insulation can handle. Small tears at the end of a run matter less than tears facing the heat source. Inspect the foil face after routing, especially where the sleeve passed over connectors or through clamps; patch or replace sections whose foil is damaged on the heat-facing side before the assembly enters service.
Is this sleeve intended for radiant heat, direct contact heat, or both?
It is positioned for radiant heat and moderate ambient zones: the foil face addresses radiation, and the layered construction adds a mechanical/abrasion barrier. It is not a direct-contact exhaust or molten-splash product, where the sleeve would touch the hot surface itself, use a thick-wall fiberglass or silicone-coated construction and treat this sleeve's rating accordingly. The continuous temperature figure for this exact build is still being confirmed; request it with your duty description before relying on a number.
How is this sleeve closed — is there a seam?
The tube is formed by crimping the foil-textile laminate along its length. Depending on the batch construction this joint is a folded crimp seam; it should be treated as the one less-robust line of the sleeve: keep the seam away from the direct radiant face where the design allows, and orient it so clamps and ties do not work on it. Confirm the seam style of the batch you receive at order stage if the route leaves no tolerance for it.
How much clearance does the sleeve need over connectors?
Size the inner diameter on the largest object the sleeve must pass over, not on the cable OD: connectors, splices and molded boots define the fit. The crimped construction does not expand like a braided sleeve, so a sleeve that clears the cable but not the connector cannot be stretched on. Allow working clearance so the sleeve slides without scuffing its own foil face, and fix both ends with ties or clamps so the foil does not rub at the entry points.
Request a quote for Aluminum Foil Textile Crimped Sleeving
Send the bundle OD and largest connector, route description with heat-source type and distance, zone temperature and quantity. We return the sleeve ID, cut lengths, temperature confirmation for this build and lead time.