Glass Fiber Corrugated High-Temp Sleeve
A corrugated thick-wall fiberglass sleeve for exhaust heat shielding and NEV wire-harness runs. The bellows-like wall articulates around bends without kinking while the thick section between folds keeps the thermal barrier. Slip-on, non-shrink, black. Three catalogue figures are under verification and are held in the data note until confirmed: the -40℃~+400℃ temperature range (grade confirmation, continuous vs peak), the Φ8–Φ27 mm ID span, and the scope of the UL94 V0 claim (which grade, what thickness, sleeve as sold or base compound only). The construction logic on this page is what the delivered product shows; the numbers wait for their test basis. Send the object OD and the route and we size the sleeve.
Why the wall is corrugated
Corrugation is geometry doing a specific job. A straight thick-wall tube holds its barrier but resists bending: force it along a route and it kinks or sits stressed. Folded into corrugations, the wall articulates at every fold: the sleeve follows bends, absorbs small movements of the line underneath, and keeps its thick section where it matters. Three consequences follow:
- Bend accommodation. The inside of a bend closes the folds, the outside opens them : that is how the sleeve takes up the radius without wall damage. Each size has a minimum radius below which the folds collapse; the value is part of the pending documentation, so state your tightest bend at RFQ.
- Barrier kept between folds. The thermal and mechanical barrier lives in the thick wall sections; the folds are articulation points, not insulation. That is why fixings belong on the crests and why a crushed fold is a service defect, not a cosmetic one.
- Expansion breathing. Over a warm line that grows and shrinks, the folds take up the length change instead of the wall loading up : relevant on exhaust-adjacent runs with hot-cold cycling.
Where Glass Fiber Corrugated High-Temperature Resistant Sleeve is used
Primary applications: exhaust heat shielding and NEV (new energy vehicle) wire-harness protection: routes where high temperature and bends arrive together: harness sections crossing exhaust proximity zones, hot-air duct runs, heater circuits. It installs over assembled runs; nothing shrinks.
How to select: ID, bend, wall, fixing
- Object OD. Measure the harness or pipe including jacket; size the ID with working clearance. The catalogued Φ8–Φ27 mm span is under verification : confirm availability for your diameter.
- Minimum bend radius. From the tightest bend on the route; confirmed per size once the corrugation geometry data is issued.
- Wall thickness and corrugation pitch. Per size : part of the pending documentation; thicker walls keep more barrier but articulate less.
- Temperature duty. State continuous and peak zone temperatures including radiant load; the verified range for the grade will be matched against them.
- Fixing. Clamp or tie at intervals on vehicle routes, on the crests, never on fold lines.
Specification
| Material | Glass fiber, corrugated thick-wall form |
|---|---|
| Wall type | Corrugated (bellows-form) thick wall |
| Shrink behaviour | Non-shrink slip-on |
| Operating temperature | Under verification : catalogue -40℃~+400℃ held pending grade data |
| ID range | Catalogued Φ8–Φ27 mm : availability confirmed at RFQ |
| Colors | Black |
| Flame classification | UL94 V0 scope under verification : not claimed on this page until the test file confirms grade, thickness and product coverage |
Common Failure Modes & How to Prevent Them
These are the failures specific to a corrugated thick-wall fiberglass sleeve, with the root cause and the prevention for each.
Folds collapsed at a tight bend
Root cause: The route bent tighter than the size's minimum radius. The folds on the inside of the bend closed past their limit and the wall crushed flat, losing both barrier and articulation at the worst point on the run.
Fix: State the tightest bend at RFQ and confirm the radius per size. Where the route cannot be relaxed, move up an ID size or split the run with a joint at the bend.
A clamp crushed the fold line
Root cause: The fixing landed on a valley instead of a crest, and the clamp load flattened the fold. A crushed fold is a permanent barrier gap and a crack starter under vibration.
Fix: Fix on the corrugation crests with wide, padded clamps sized to the crest diameter. Never clamp on a valley, and re-check fixings after any route service.
The sleeve was pulled straight over a bend
Root cause: Installation stretched the wall tight along the route instead of letting the folds take up the bends. The corrugations loaded against each other and the wall went into permanent stress at the first thermal cycle.
Fix: Lay the sleeve over the route so the corrugations follow the bends naturally: feed it on, do not draw it taut. The folds should sit evenly spaced along the run after install.
Cut ends shed glass particles
Root cause: A coarse cut left the thick wall edge frayed and glass-fibre-prickly: a handling hazard and a fit problem at end clamps.
Fix: Cut with shears or a fine abrasive wheel in one pass, and dress the end before assembly. Verified end-treatment guidance for the grade ships with the grade data.
The flame rating was assumed to cover the finished sleeve
Root cause: A UL94 V0 classification from the base compound was carried into drawings as a sleeve rating. The tested sample, its thickness and the certified scope never matched the finished product. A gap an auditor or incident investigation will find.
Fix: Hold the classification claim until the verified scope is issued (tested grade, tested thickness, sleeve-as-sold coverage), and design flame behaviour from the route's actual requirements in the meantime.
Frequently asked questions
What does the corrugated wall change compared with a straight sleeve?
It trades rigidity for articulation. A straight thick-wall tube resists bending; folded into corrugations, the wall can flex at every fold, so the sleeve follows a routed bend without kinking or taking a set. The folds also let the wall breathe over a warm line that expands and contracts in service. The cost is at the folds themselves: each one is a slightly thinner, locally stressed point, which is why the wall is made thick between folds and why the folds decide the minimum bend radius.
How should bend radius and ID be selected?
ID from the object: measure the harness section or pipe including any jacket, and take the next size up with working clearance. The catalogued ID span for this product is under verification, so confirm availability against your diameter rather than assuming it. Bend radius from the route: the minimum radius is set by how far the corrugations can close on the inside of the bend without collapsing; state the tightest bend on the run and we confirm it against the size.
What exactly is covered by the UL94 V0 claim?
Until the test file is verified, nothing is printed here. UL94 V0 is a pass/fail flame classification for a specific material sample in a specific thickness. It is not transferable automatically to every size of a finished sleeve. What is being confirmed: which material grade was tested, at what thickness, and whether the certificate covers this sleeving as sold or only its base compound. The claim will be printed with that scope once supplied; until then the sleeve is described as flame-resistant fiberglass, without a classification value.
Why choose a corrugated fiberglass wall over a braided or coated sleeve?
For barrier thickness that survives bending. A braid bends easily but is open and thin; a smooth thick tube insulates but will not follow a route. The corrugated wall is the only form that keeps a thick inorganic barrier AND articulates. Which is why it sits on exhaust runs and NEV harness sections where heat load and bends arrive together. Where the run is straight, a smooth or braided sleeve is usually simpler; where heat and bends combine, this is the construction.
How is it installed on a harness or pipe run?
Push it on over the section to be protected (no heat, no recovery step), and let the corrugations take up the route's bends naturally instead of pulling the wall straight. Fix at intervals with clamps or ties sized to the corrugation crests so the sleeve cannot migrate under vibration, and keep fixings off the fold lines where the wall is thinnest. Cut to length with shears or an abrasive wheel; end treatment guidance comes with the verified grade data.
What temperature service is confirmed for this sleeve?
None is published yet. The catalogue carried -40℃~+400℃ as a single range; that range is held pending verification of the exact grade. Both the low end and the continuous-versus-peak split at the high end need the grade's test data before they are printed. Fiberglass as a material family tolerates high temperature; the rating for this specific sleeve belongs to its grade. Design from your own zone temperatures and confirm with us at RFQ in the meantime.
Request a quote for Glass Fiber Corrugated High-Temperature Resistant Sleeve
Send the object OD, the tightest bend on the route, the zone temperatures and quantity. We return the size code, the verified grade data sheet and lead time.
Certifications & Compliance
The UL94 V0 classification for this product is being confirmed with its test file: tested grade, tested thickness and whether the certificate covers the sleeving as sold or the base compound. Details are held in the data note above until verified. Tell us your target market (EU / US / Asia) and we align the documentation to your filing.
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Size range & specification notes
Catalogued ID span Φ8–Φ27 mm, availability confirmed at RFQ; corrugation geometry and bend radius per size are held in the data note above until verified.