Silicone hose is the default flexible conduit where high temperature meets purity: standard compounds run continuously at −60 °C to +180 °C (special compounds higher, check the datasheet), stay flexible in the cold, and, when platinum-cured, meet FDA 21 CFR 177.2600 and USP Class VI for food and pharmaceutical contact. Its limits are just as sharp: silicone is not suitable for petroleum fuels and oils, aromatic solvents, concentrated chemicals, or high-pressure steam. This guide is the technical reference, material science, construction types, ratings, standards, and cost of ownership.
If you are at the specification stage, the companion pieces silicone hose: everything buyers need to know before specifying and silicone hose selection: 12 criteria cover the pitfalls and the step-by-step checklist; size-by-size ratings are in silicone hose specifications explained.
What Is Silicone Hose and How Is It Made?
Silicone hose is a flexible tube of polydimethylsiloxane (PDMS) elastomer, reinforced as required with polyester, aramid, or stainless-steel wire. The Si, O, Si backbone, rather than the carbon chain of NBR or neoprene, gives the material its defining behaviour: it does not oxidise and harden at high temperature the way carbon-chain rubbers do, it stays elastic far below freezing, and it is inherently resistant to UV and ozone.
Manufacturing starts from high-consistency rubber (HCR) or liquid silicone rubber (LSR), compounded with fillers and a cure system. Two cure chemistries matter commercially. Peroxide curing is economical but leaves volatile by-products in the compound. Platinum (addition) curing crosslinks without those by-products, which is why food-grade and pharmaceutical hose is specified platinum-cured; a post-cure oven cycle then drives off residual volatiles. The tube is extruded or mandrel-wrapped, reinforcement plies are applied, and the hose is cured under heat and pressure.
What Types of Silicone Hose Exist?
Unreinforced Silicone Tubing
Extruded tubing in wall thicknesses from roughly 0.5 mm to 6 mm serves low-pressure duties, peristaltic pump lines, laboratory transfer, breathers, typically up to about 1.5 bar working pressure. Because unreinforced tubing has no braid to share the load, a higher burst safety margin (around 5:1) is prudent, and vacuum resistance is poor unless the wall is thick relative to bore.
Fabric-Reinforced Silicone Hose
One or more polyester or aramid plies embedded between silicone layers resist radial expansion. Indicative ratings run from a few bar for single-ply large-bore hose up to around 20 bar for multi-ply small-bore constructions, and as with every hose, working pressure falls as bore diameter rises, so read the rating per size. This category covers most coolant, charge-air, and light industrial process hose.
Wire-Reinforced Silicone Hose
An embedded stainless-steel helix adds collapse resistance, so the hose handles both pressure and full vacuum in the correct wall thickness. Typical duties: engine-room cooling water, industrial vacuum lines, suction service. Fabric braid alone does not provide equivalent vacuum resistance, a frequent specification error.
Specialty Constructions
Aramid-reinforced hose raises the burst-to-weight ratio for motorsport and aerospace; convoluted silicone hose absorbs misalignment and vibration; fluorosilicone-lined hose adds resistance to fuels, oils, and aromatic hydrocarbons, precisely the media standard silicone cannot handle, while keeping the silicone outer layers' thermal stability.
What Are the Key Performance Parameters?
Indicative values for the main categories; always verify against the manufacturer's datasheet, and remember pressure ratings are quoted at +20 °C and derate with temperature.
| Parameter | Unreinforced | Fabric-reinforced | Wire-reinforced | Fluorosilicone-lined |
|---|---|---|---|---|
| Continuous temperature | −60 °C to +180 °C | −60 °C to +180 °C (special compounds higher) | −60 °C to +180 °C (special compounds higher) | −55 °C to +180 °C |
| Short-term peak | per datasheet, up to ~+220…+250 °C for high-temp compounds | per datasheet | per datasheet | per datasheet |
| Typical working pressure | ≤ ~1.5 bar | up to ~20 bar (falls as DN rises) | up to ~25 bar (falls as DN rises) | mid-range |
| Vacuum resistance | poor | limited | good (full vacuum with correct wall) | limited |
| Fuel/oil resistance | poor | poor | poor | good |
| Food-contact versions | available | available | available | not standard |
Key takeaway: standard silicone is not fuel- or oil-resistant, and it swells badly in aromatics such as toluene and xylene. Specifying plain silicone against petroleum media is the most common, and most expensive, silicone hose error.
On safety factors: reinforced silicone hose is generally designed around a 4:1 burst-to-working-pressure ratio and unreinforced tubing around 5:1, but there is no single normative number, confirm the ratio and the proof-test pressure (≈1.5 × WP) on the type-test data. No "EN ISO 6945" safety-factor requirement exists; ISO 6945 is a cover-abrasion test method.
Where Is Silicone Hose Used?
Automotive and Motorsport
Silicone dominates performance cooling and charge-air systems: radiator and intercooler hoses at 90–120 °C coolant temperature and 1.5–2.0 bar system pressure, and turbo-side hoses exposed to heat soak beyond what EPDM survives. SAE J20 is the reference performance standard for automotive coolant hose.
Food and Beverage Processing
Platinum-cured silicone hose handles product transfer and CIP circuits cycling between cold product (~2 °C) and hot caustic/acid rinses (85–90 °C). Compliance rests on FDA 21 CFR 177.2600 (rubber articles for repeated food contact) and, in the EU, the EC 1935/2004 framework with GMP Regulation 2023/2006, note that Regulation 10/2011/EU applies to plastics only and never to silicone or rubber. For dairy and hygienic duty, 3-A Sanitary Standards add bore-finish and cleanability requirements.
Pharmaceutical and Biotechnology
Pharma-grade silicone hose faces the strictest extractables and leachables (E&L) scrutiny: USP Class VI biological reactivity, European Pharmacopoeia 3.1.9 (silicone elastomer for closures and tubing), platinum cure, smooth bore finish, and full batch traceability are standard procurement requirements for WFI and API transfer.
HVAC, Building Services, and Hot Air
Fabric-reinforced silicone hose makes flexible connections at air handlers and heat pumps with glycol-water mixes, and convoluted silicone ducting handles hot-air conveyance and oven ventilation. UV and ozone resistance make it the rooftop choice where EPDM covers degrade.
What About Steam?
Be precise here. Silicone tolerates short sterilisation cycles, autoclaving/SIP at 134 °C saturated steam is routine in pharma and food plants when the compound is rated for it. But silicone hose is not a steam hose: continuous saturated-steam transfer belongs to rubber steam hose per EN ISO 6134 (type 1: 6 bar / 164 °C; type 2: 18 bar / 210 °C), assembled only with bolted safety clamps per EN 14420-3 / DIN 2817, never crimped ferrules or Camlock couplings. Silicone is likewise not suitable for strong acids, concentrated alkalis, or ketone-heavy solvent duty; evaluate PTFE-lined alternatives or EPDM chemical hose instead.
How Should Silicone Hose Be Installed?
Three practices prevent most field failures:
- Cut square, fit clean. Use a sharp blade perpendicular to the axis; ragged cuts concentrate stress and split under pressure cycling. Lubricate spigots with water or a food-grade lubricant, never petroleum grease, which swells the silicone.
- Re-torque clamps. Silicone creeps under compressive clamp load: clamp tension can drop 10–20 % during the first heat cycles. Torque worm-drive clamps to specification, then re-torque after the first ~24 hours of service.
- Respect the bend radius. Roughly 2 × OD for unreinforced tubing and 3–4 × OD for fabric-reinforced hose; below that, the bore kinks and fatigue cracks start at the inner radius. Use moulded elbows for 90° turns in confined spaces.
For inspection routines and failure-mode diagnosis (thermal hardening, delamination, clamp cold-flow), see the buyer's specification guide.
Which Standards Govern Silicone Hose?
- FDA 21 CFR 177.2600, rubber articles for repeated food contact (USA); a formulation-level compliance, not a product certificate.
- EC 1935/2004 + GMP 2023/2006: EU food-contact framework; silicone falls here (not under the plastics regulation 10/2011/EU). National measures such as the German BfR Recommendation XV (silicones) are commonly referenced.
- USP Class VI / Ph. Eur. 3.1.9, biological reactivity and pharmacopoeial requirements for pharmaceutical-grade silicone.
- 3-A Sanitary Standards, hygienic hose assemblies for dairy and food service, including bore surface finish and cleanability.
- SAE J20, automotive coolant hose performance classes.
- ATEX 2014/34/EU, where flammable vapours or powders are present, specify a static-dissipative compound and verify the assembly's electrical resistance by measurement per ISO 8031.
Compliance note: every food or pharma declaration applies to a specific hose version and medium group. FDA 177.2600 compliance is necessary but not sufficient for drug-product contact: USP Class VI and E&L profiling come on top.
What Does Silicone Hose Really Cost?
Unit price runs roughly 2–4 × EPDM or NBR equivalents, but total cost of ownership favours silicone in high-temperature and regulated service. Correctly specified silicone coolant hose commonly outlasts EPDM by a factor of two to three; in food and pharma plants the platinum-cure premium buys lower regulatory risk, faster cleaning validation, and longer replacement intervals. Weigh planned replacement labour, downtime cost (a production stop costs far more per hour than any hose), and the consequence of a contamination event, in EUR terms, one rejected pharmaceutical batch exceeds a decade of hose spend.
Key Takeaways
- Silicone hose runs −60 °C to +180 °C continuously (special compounds higher per datasheet) and stays flexible at low temperature, the default beyond EPDM's thermal limit.
- Standard silicone must never see petroleum fuels, oils, or aromatics; specify a fluorosilicone liner or a different hose family for hydrocarbons.
- Silicone is not for continuous steam, strong acids, or concentrated chemicals, steam transfer belongs to EN ISO 6134 rubber steam hose with bolted safety clamps; short autoclave/SIP cycles at 134 °C are acceptable when rated.
- Food and pharma silicone must be platinum-cured; compliance rests on FDA 21 CFR 177.2600, EC 1935/2004, USP Class VI, and Ph. Eur. 3.1.9: Regulation 10/2011/EU covers plastics only and never silicone.
- Working pressure falls as bore rises; design reinforced hose around ~4:1 burst-to-WP (unreinforced ~5:1) and confirm on the type-test data.
- Match reinforcement to the duty: fabric braid does not give wire-helix vacuum resistance. Re-torque clamps after first heat cycling.
Browse silicone and high-temperature hose in our industrial hoses range or search silicone hose directly, and match the clamping hardware from industrial fittings. For food-grade, pharma, or high-temperature duties, send the application parameters, our engineering team selects the hose and fittings, assembles, and pressure-tests every assembly before dispatch.