PTFE Composite Hose for Aggressive Chemicals

A ptfe composite hose is the build you specify after a polypropylene liner has already failed, or before it does. This one covers bore 25 mm to 254 mm (1 in to 10 in), working pressure 20 bar (290 psi) to 76 mm and 15 bar (218 psi) from 102 mm, service temperature -30°C to +120°C, and a 20 m standard length. The wetted surface is PTFE film backed by multiple plies of PP film, inside an SS316L inner helix. It is built for toluene, xylene, dichloromethane, esters, ketones and 98% sulphuric acid. Confirm the medium and its temperature with us in writing before you order.

Présentation du produit

This is a non-vulcanised, multi-layer thermoplastic hose for suction and discharge of aggressive chemicals, in the liquid-service classes of EN 13765:2018, Type 2 and Type 3 depending on bore. Its layers are compressed between two steel helices rather than bonded, which explains both its flexibility and its vacuum behaviour.

In one sentence, the ptfe composite hose is a PTFE film liner over plies of PP film, a carcass of PP fabric and film, a PVC-coated fabric cover, an SS316L inner helix and a galvanised or SS316L outer helix.

Three numbers frame the specification: 20 bar to 76 mm, -30°C to +120°C, and a 20 m standard length that cuts joints on a long run.

The advantages follow from the liner. PTFE is the most inert polymer in hose construction, so one hose covers media that would otherwise need several compounds. The PP plies add body and slow permeation, and weight stays low, 0.8 kg/m at 25 mm to 7.3 kg/m at 254 mm.

Typical users are specialty chemical plants, pharmaceutical and agrochemical works, paint manufacturers, solvent terminals and surface treatment lines, with diaphragm pumps, reactor feed spools, filter presses and tank car arms.

The problem it solves is the batch that attacks everything else. A plant running toluene, then MEK, then a nitric blend cannot stock three hoses, nor risk a liner that swells between campaigns. PTFE does not swell, and the helix holds the bore open.

Quality is controlled at the assembly, not only at the roll: every assembly is proof tested, each crimp is recorded against its serial number, and the hose traces back to its film and fabric lots. The factory holds ISO 9001 and tests this range against EN 13765:2018.

Product Advantages of the PTFE Composite Hose

• Fluoropolymer wetted surface. PTFE resists aromatic, chlorinated and oxidising media that attack a PP liner.
• 20 bar to 76 mm. The higher rating covers boosted transfer and long discharge runs.
• Full suction duty. The SS316L inner helix holds the bore open under vacuum.
• One hose, many campaigns. No swelling between products, so changeovers stay short.
• 20 m standard length. Fewer flanged joints on jetty, dock and reactor runs.
• Crimped fittings, digital records. Every assembly is swaged in house and traceable to batch.

Applicable users: specialty and fine chemical plants, paint and coatings producers, solvent terminals, pharmaceutical utilities, surface treatment lines, and distributors who stock a fluoropolymer-lined hose for escalation cases.

Detailed Technical Specifications

• Temperature: -30°C to +120°C, the highest ceiling in the chemical range. The PP plies behind the film see the same heat, so recheck any duty above 100°C.
• Pressure step: 20 bar holds to 76 mm, then the schedule steps to 15 bar from 102 mm. Do not assume 20 bar across the table.
• Safety factor: 3:1 minimum as published. Proof test is 1.5 times working pressure, 30 bar on the 20 bar sizes and 22.5 bar on the 15 bar sizes.
• Vacuum: built for suction, but the sheet gives no bar figure. We work to 0.9 bar full vacuum and confirm it per order.
• Custom lengths: 20 m is standard; shorter lengths are crimped and proof tested to order, and longer runs use flanged spools.

Structure et matériaux

The ptfe composite hose is five functional layers, none of them glued to the next.

• Inner helix: SS316L wire, formed as a helix and compressed into the liner. It resists vacuum collapse and keeps the bore round at the bend.
• Liner: PTFE film as the wetted surface, over multiple plies of polypropylene film. Only the PTFE touches the medium.
• Carcass: polypropylene fabrics and films with polyester vapor barrier plies, carrying axial load and slowing permeation through the wall.
• Cover: polypropylene fabric and film under an abrasion-resistant PVC-coated fabric, resisting splash, sunlight and dragging on concrete.
• Outer helix: high-tensile hot-dip galvanised steel as standard, or SS304 and SS316L for salt air and washdown duty. It carries hoop load and shields the carcass.

Why the composite build holds up

The inner helix resists collapse. When a pump pulls vacuum it holds the bore open while the fabric plies take the axial pull, and a wire-braided rubber hose of the same bore needs a separate suction grade to do the same job. That is the difference a plant notices first, because a collapsed bore cannot be recovered by pressure.

Hoop load lands on the outer wire, which also takes the abrasion before it reaches the carcass. Between the helices the fabric plies lie at an angle, so pressure becomes tension in the fabric rather than strain in the liner. Nothing is vulcanised, so there is no cure system, plasticiser or carbon black to leach.

Because the layers are compressed rather than bonded, the hose flexes by letting plies slide a fraction of a millimetre. That is why the bend radius at 102 mm bore is 589 mm and why the hose coils for transport without taking a set. The trade is that the crimp, not a chemical bond, holds the structure together, so fitting selection and crimp quality decide service life more than the liner does. Hoop stress also rises with bore at the same pressure, which is why the schedule steps from 20 bar to 15 bar above 76 mm.

Safety factor, proof pressure and burst margin

The published 20 bar is a working pressure, not a failure point. A 3:1 minimum design factor puts expected burst near 60 bar on the 20 bar sizes and near 45 bar on the 15 bar sizes. EN 13765:2018 works on a 4:1 basis for the classes it covers, so a buyer who needs 4:1 for a safety case should ask which factor the certificate for their order states.

Proof testing is the practical control. We test every assembly at 1.5 times working pressure, 30 bar on the 20 bar sizes, and hold it long enough to reveal a bad crimp, a pinhole in the film or a damaged helix. A sample test describes a batch; a proof test on every assembly describes the hose in your hand. Ask also whether the factor is quoted at ambient or at the top of the range, and whether records are kept per serial number.

Chemical Compatibility and Media Guide

Ratings are guidance for the PTFE liner at ambient temperature with no contamination. They open the quotation conversation rather than replace a written confirmation; the PP backing plies are why a few entries read conservative.

Three rules for reading the chart. Temperature changes everything, so a rating that holds at 20°C may not hold at 110°C. Concentration matters more than the name, since 98% sulphuric acid behaves nothing like a 30% solution. Contact time counts too: a 20 minute transfer and a 20 day standing column are different duties. Ask for the full compatibility chart as a PDF.

Applications and Industries

• Specialty and fine chemical plants: reactor feed and discharge spools, filter press connections and drum decanting where the campaign changes weekly.
• Paint, coatings and ink manufacturing: toluene, xylene, MEK and ethyl acetate transfer at mixers, bead mills and filling heads.
• Pharmaceutical and agrochemical works: solvent recovery, drum unloading and cleaning-in-place lines.
• Chlorinated solvent and degreasing operations: trichloroethylene and dichloromethane at vapor degreasers, stills and transfer pumps.
• Metal finishing and pickling: nitric, phosphoric and mixed acid lines to pickling tanks.
• Solvent terminals and distributors: 20 m assemblies for tank car unloading and drum filling, supplied as complete hose assembly units with your ends fitted.

Selection Guide for PTFE Composite Hose

Size, flow and pressure drop

Bore follows flow and the pressure drop you can live with, not the pump outlet alone. Keep liquid velocity near 2 m/s continuous and below 3 m/s intermittent, because higher velocity wears the liner at bends and raises static. A 25 mm bore moves about 3.5 m3/h at 2 m/s and a 254 mm bore 365 m3/h. Go one size up if a run needs more than two 90 degree bends.

End fittings and hose assembly

Fittings are crimped, not clamped, and we swage them in house with digital records for every assembly. Ends on offer are NPT and BSP male, camlock, fixed and floating flange, reducing flange, tank coupling and 37 degree flare adapters.

Specify material, thread standard and gasket face together, because a stainless hose with a carbon steel fitting corrodes at the thread.

How it compares

Against the EN 13765 types, this hose covers the liquid-service work of Type 2 and Type 3 with a fluoropolymer liner, and against rubber it wins on chemical breadth and vacuum.

What drives the price

Four things move the cost: bore, liner, helix material and length. PTFE film is the largest input and scales with surface area, so a 254 mm bore is not a linear step from a 102 mm one. Stainless helices cost more than galvanised, and a short length costs more per metre than a roll, because crimping and testing labour is identical.

Compare quotes on the same basis, because a low headline often leaves out fittings or packing. On bulk and wholesale orders the lever is batching several bores into one order and one port.

Common selection mistakes

• Buying PTFE for the wrong reason. A dilute acid at ambient needs no fluoropolymer; a PP liner does the same job for less.
• Reading 20 bar across the table. The 102 mm to 254 mm sizes are rated 15 bar.
• Ignoring the PP backing plies. A medium that permeates PTFE slowly still reaches them, so ask about permeation, not just resistance.
• Mixing fitting materials. A stainless helix with a carbon steel flange creates a corrosion cell at the joint.

Installation, Operation and Maintenance

Installation

• Respect the minimum bend radius, 152 mm at 25 mm bore rising to 1200 mm at 254 mm.
• Support horizontal runs every 1.5 m on a saddle, not a rope.

Keep a straight length equal to one bore behind every ferrule, or the crimp works in bending.

• Fit a swivel or short elbow at the fixed end when the hose must twist during coupling.
• Never lift a filled assembly by the fittings, and fit a protective sleeve at a steel edge.

Inspection and retirement

Check the cover for cuts, blisters and soft spots before each shift, and look for movement between ferrule and hose at the crimp. A bulge near a fitting means the carcass has begun to fail. Check for liner collapse after any vacuum event; a flattened bore will not recover.

Cleaning, storage and service life

Flush with water or a compatible solvent after each product change, then drain and hang with both ends open. PTFE cleans down well, which is why plants accept the cost. Store coiled at or above the minimum bend radius, away from sunlight and ozone sources. Service life follows bending at the fitting, dragging and chemical exposure, so log medium, temperature and hours.

Quality Assurance and Test Data

Incoming PTFE film, PP film, fabric and wire are inspected against certificates. Liner film is wound ply on ply, the carcass is built over the inner helix, and the wall is compressed without any cure. Crimping runs on a press that logs pressure, stroke and die set against the serial. Each hose is proof tested, marked and packed.

Test coverage is hydrostatic proof to EN ISO 1402, impulse to EN ISO 6803, resistance to EN ISO 8031 where a conductive build is specified, bend to EN ISO 1746 and dimensions to EN ISO 1307. Export packing is film plus a plywood case for LCL, or bubble wrap on a reel for FCL.

Standards and Certifications

Company certifications: ISO 9001 and ISO 18752, with CE, CCS, ABS, DNV, MSHA, API, GOST-R, RoHS, California Proposition 65 and MA metrology accreditation. Scope varies by product and market, so ask for the certificates that apply to your order.

Foire aux questions

What is the hose made of?

A PTFE film liner over PP film plies, a PP carcass, a PVC-coated cover, an SS316L inner helix and a galvanised or stainless outer helix.

What does the 20 bar rating mean?

It is the working pressure to 76 mm bore; from 102 mm the published rating is 15 bar. Both carry a 3:1 minimum design factor and a 1.5x proof test.

Can it handle vacuum?

Yes. The SS316L inner helix carries the collapsing load. The sheet gives no bar figure, so we quote 0.9 bar as the working limit and confirm it on the order.

What is the temperature limit?

-30°C to +120°C, the highest ceiling in the chemical range. Above 100°C the PP plies behind the film become the limiting layer.

Will it handle my solvent?

If the solvent is aromatic, chlorinated, an ester, a ketone or a strong oxidising acid, this is the right liner. A dilute acid at ambient works in a cheaper PP liner.

How is it different from a rubber hose?

A rubber hose is vulcanised with bonded layers. This one is compressed rather than cured, so full vacuum comes without added stiffness.

When should I move up or down the range?

Down to the standard chemical composite hose for a dilute acid below 100°C. Up to the heavy duty chemical composite hose for larger bore at 20 bar with an 80°C ceiling.

What is the smallest order you accept?

Sampling on a new build is quoted at 48 hours and a standard bulk run takes about 7 days. Minimum quantity depends on bore and fitting mix.

How do I get a quote or a PDF datasheet?

Give us the medium, concentration, temperature, pressure, bore, length and end connection through the enquiry form. You get a quotation, the datasheet PDF and the compatibility chart.

Why Source Composite Hose from HENGHUA

HENGHUA builds composite hose at an 18,000 m2 plant in Hebei, with a Tianjin office handling export. Eight high-speed lines produce 25 million metres a year for customers in 70+ countries. Scale matters for the ptfe composite hose because film forming, helix forming and crimping decide service life, and all three happen under one roof, so a 254 mm assembly carries the same crimp record as a 25 mm one.

Certification covers ISO 9001 and ISO 18752, plus CE, CCS, ABS, DNV, API, GOST-R, RoHS, California Proposition 65 and MA where the product and market require them. For this build the documents that matter are the EN 13765:2018 test report, proof records for your serial numbers, and material certificates for the PTFE film and the helix wire.

Assembly capability is the practical difference. We crimp in house, hold NPT, BSP, camlock and flange ends in stock, and supply a complete hose assembly rather than hose plus loose fittings. OEM and ODM work covers your label, packaging and fitting schedule, which removes a local assembly step for a distributor, and the liability with it.

A new liner build samples in 48 hours; a standard bulk run ships inside 7 days with tracking. Sales engineers read compatibility charts daily, so a permeation question gets a specific answer; after-sales starts from the batch record. As a manufacturer and exporter we can also tell you which standard your market will test against.

Demander un devis

Give us the medium and its strength, the service temperature, the working pressure, bore, length, connection and discharge port. With those answers we select the liner build, helix material and fittings, then price the ptfe composite hose against your duty rather than a catalogue guess. You will receive a quotation, the datasheet PDF, the compatibility chart, and a sample where the order size justifies one. Use the site contact form, or start from the composite hose range.