Composite hose selection is a document-led process: match the film/liner material to the fluid, confirm working pressure and vacuum duty, fix the temperature envelope, and verify conformity to the governing standard — EN 13765 for hydrocarbons, solvents and chemicals, EN 13766 for LPG/LNG. Because a composite hose is a multi-layer construction (thermoplastic films and fabrics between an inner and outer wire helix) rather than a vulcanised tube, every one of those choices is configurable, which is exactly why an unstructured purchase goes wrong. This guide walks the 11 criteria in purchase-order sequence.
Quick answer: Verify, in order: (1) every fluid incl. cleaning media against the liner's resistance chart at temperature, (2) working pressure incl. surges — EN 13765 hoses typically run 7–14 bar with a 4:1 burst margin and 1.5 × WP proof test, (3) vacuum rating, (4) temperature envelope, (5) DN and length vs bend radius, (6) end-fitting type and material, (7) electrical continuity for ATEX service (≤10⁶ Ω, tested per ISO 8031), (8) the governing standard and certificates, (9) bonding/earthing, (10) marking and colour coding, (11) inspection and retirement policy. One unverified item is enough to cause a release.
This is the buying checklist of the composite cluster. For the parameter deep-dive with pressure/temperature/bend-radius tables, see Composite Hose Specifications Explained; for construction fundamentals, the complete technical guide covers layer architecture in depth.
What Is a Composite Hose, and What Is It Not?
A composite hose is built from an inner wire helix (supports the bore against vacuum), multiple alternating plies of thermoplastic film and woven fabric (containment and chemical barrier), and an outer wire helix (hoop strength and mechanical protection). No vulcanisation takes place, the plies are bonded mechanically, which makes the hose light, flexible, and configurable for chemical duty by film selection: polypropylene (PP) for many acids, alkalis and general chemicals; polyamide/PE films for hydrocarbon products; PTFE for aggressive solvents, concentrated acids and aromatics; PVDF for chlorinated media. The layered build also slows a liner pinhole from becoming an instant release, permeation shows at the cover before catastrophic failure.
Two boundaries to respect from the start:
- Composite hose is not a steam hose. Steam duty requires a hose per EN ISO 6134 with bolted safety clamps (EN 14420-3 / DIN 2817), a completely different product class.
- The end fitting is part of the pressure envelope. Fittings are swaged onto the multi-layer body; the hose/fitting combination must be tested as an assembly (proof at 1.5 × WP), not rated from the fitting alone.
The 11-Point Composite Hose Selection Checklist
1. Identify every fluid, including the cleaning media
List each product the hose will carry, plus flushing agents and purge media, and check each against the film manufacturer's resistance chart at the actual operating temperature. Compatibility is temperature-dependent: a PP liner rated "suitable" at 20 °C can degrade at 60 °C in the same chemical.
2. State the working pressure including surges
Typical EN 13765 assemblies run 7–14 bar working pressure with a minimum 4:1 burst margin and a 1.5 × WP factory proof test; LPG/LNG composite hoses to EN 13766 reach higher ratings (up to 25 bar). Include water-hammer and pump-surge peaks in the stated maximum, valve closure on a loading bay routinely exceeds steady-state pressure.
3. Specify vacuum duty explicitly
Most composite hoses tolerate significant vacuum because of the inner wire, but the rating depends on wire gauge, DN, and build, larger bores need heavier inner wire for sustained suction. State the required vacuum level in the enquiry; never assume full vacuum from the construction type.
4. Define the temperature envelope
Record minimum ambient (cold start) and maximum fluid temperature. Typical composite envelopes run from about −30 °C (−40 °C for some builds) to +80…+100 °C depending on film selection; pressure ratings are quoted at +20 °C and derate as temperature rises, request the manufacturer's correction data rather than applying the nameplate figure hot.
5. Fix DN and length against the bend radius
Match DN to the pipework and target sensible flow velocity (≈1–3 m/s gravity/low pressure, up to ~5 m/s forced flow, higher erodes film plies). Order enough length that the minimum bend radius is respected in every articulation position: overlong hoses drag and abrade, underlong hoses kink. A hose habitually worked near its MBR consumes fatigue life several times faster.
6. Select the end-fitting type and material separately from the liner
Flanged (EN 1092-1 PN10/PN16 or ASME B16.5 Class 150), BSP or NPT threaded, TW tank-truck, or Camlock per EN 14420-7, noting that Camlock is for liquids only, never compressed air or gases, and that A/E/F are the male adapters while B/C/D are the female couplers. Fitting material (carbon steel, 316/316L stainless, aluminium) is a chemical-compatibility decision independent of the liner: 316L for acids and chlorinated media, carbon steel only for petroleum hydrocarbons, aluminium where weight matters and chemistry allows. Browse industrial fittings for the coupling series.
7. Verify electrical continuity for flammable service
In ATEX-classified zones (Directive 2014/34/EU) and for low-flashpoint products, specify an electrically continuous assembly, the common acceptance criterion is resistance ≤10⁶ Ω end-fitting to end-fitting, measured per ISO 8031, and re-verify after any fitting change. This is a hard safety requirement, not an optional upgrade.
8. Name the governing standard and demand the certificates
EN 13765 (thermoplastic multi-layer hoses for hydrocarbons, solvents and chemicals: Type 2 is commonly specified for petroleum products, Type 3 for chemical duty) or EN 13766 (LPG/LNG). Marine note: EN 1765 covers rubber oil suction and discharge assemblies; composite assemblies are certified to the EN 13765 family, and terminal operators commonly overlay OCIMF operational guidance contractually. Require the type-test certificate for the actual configuration plus the assembly's individual hydrostatic test certificate, a generic family approval fails an HSSE audit.
9. Plan bonding and earthing
Confirm how earthing clamps or bonding cables interface with the end fittings, and follow IEC 60079-32-1 electrostatics guidance for flammable transfer. Bond before any valve opens.
10. Check marking and colour coding
EN 13765 requires permanent marking: DN, working pressure, type, manufacture date, and standard number; many sites add colour-coded covers by product family. An unmarked hose is untraceable, reject it at goods-in.
11. Agree the inspection and retirement policy up front
Typical practice: visual inspection before use, periodic hydrostatic test at 1.5 × WP (commonly 6–12-month intervals in petroleum/chemical duty, per site procedure), resistance re-test for conductive types, and a hose register keyed to serial numbers. Retirement triggers: any kink (a single over-bend event compromises the wire), outer-wire corrosion or damage, fitting movement, or test failure, plus a fixed service-life ceiling that many operators set at 5–10 years depending on severity.
Where Composite Hose Earns Its Premium
Composite assemblies cost more than single-wall rubber hose of the same DN, but at DN 100 a composite hose is roughly 40 % lighter than its rubber equivalent, which operators feel in manual handling on tanker bays and manifolds, and the layered build gives early visual warning of liner permeation instead of sudden release. On a loading bay handling hundreds of connections a year, where an unplanned stop costs from several hundred to a few thousand EUR per hour, one avoided failure typically covers years of the specification premium. Budget replacement as planned OPEX on the agreed retirement cycle, emergency procurement carries a 20–40 % price penalty.
Typical duties by sector: road-tanker and rail loading of fuels and chemicals, ship-to-shore transfer, tank-farm manifolds, and solvent handling in ATEX areas, see the industries overview for sector-specific guidance.
Specify with the Checklist in Hand
Compare liner types and DN ranges in industrial hoses or search stock directly for composite hose. If any of the 11 items is unresolved, chemical compatibility at temperature, ATEX continuity, or the certificate package — send us the checklist: our engineering team selects hose and fittings, swages, pressure-tests the assembly at 1.5 × WP, and supplies the conformity documents your audit requires.