Calibrated Polyamide Tube Medifly PATR24 Black, Ø 2×4 mm, PA12 TRUCK, Black

1. Purpose and Operating Principle

It resists engine oils, diesel fuel, brake fluids, ozone, UV radiation, and sharp temperature swings (−60 to +80 °C). Precision calibration of the 4.0 mm outer diameter ensures a tight, secure fit in compression and collet fittings — the tube is intended for pneumatic brake circuits of trucks, buses, trailers, and special vehicles.

2. Technical Specifications

⚠️ Unconfirmed parameters:

• Exact weight of a 100 m reel (approx. ~1.25 kg — confirm at shipping).
• Availability of the compact Fast Fly Box packaging (10×10 m) for repair kits.

3. Design Features

Part number breakdown:

Design solutions:

• Compliance with the DIN 73378 / DIN 74324 automotive standards — full certification for original equipment and repair of pneumatic brake systems on road vehicles.
• Extreme cold resistance (down to −60 °C) — PA12 polyamide retains high impact toughness and doesn’t crack even in severe cold.
• Black, UV-stabilized carbon-black compound — protects the polymer structure from UV degradation when routed along the vehicle frame.

4. Installation Recommendations

• Cut the tube strictly at a 90° angle with a guillotine tube cutter — an uneven cut or burrs will damage the collet or O-ring seal in the automotive fitting.
• Suitable for 4 mm automotive quick-connect collet fittings (VOSS, Camozzi, Raufoss) and compression union fittings with an insert ring — always use an internal support bushing/sleeve for thin-walled tubes.
• Do not exceed the minimum bend radius of 15 mm — use angled fittings for sharper routing turns.
• When operating at elevated temperatures (e.g., in the engine bay), reduce the working pressure: at +40 °C — 37.8 bar, at +80 °C — 29.4 bar.
• For sections near the exhaust manifold, use additional heat-protective sleeving — the rated +80 °C limit is calculated without accounting for radiant heat from hot components.

5. Alternatives and Comparison

Comparison within the Medifly range:

6. Common Mistakes

• Installing in a compression fitting without an internal support sleeve — the insert ring on an automotive fitting without a sleeve can crush the 1.0 mm polyamide wall.
• Using a standard polyurethane tube in a brake circuit instead of PATR24 — standard PU is not certified to DIN 73378/74324 and softens on contact with automotive chemicals and heat.
• Cutting with pliers instead of a guillotine cutter — crushes the 4 mm end, creating a risk of air leakage in the brake line.
• Exceeding the +80 °C temperature limit without thermal protection near the exhaust manifold.

7. Application

Pneumatic brake systems (brake control circuits for trucks, tractor units, buses, and trailers per DIN 73378/74324), air suspension and transmission control (ride-height adjustment lines and pneumatic gear shifting), fuel and lubrication lines (pressurized diesel fuel, oils, and lubricant delivery), high-pressure industrial automation (control of low-pressure hydraulics and high-pressure pneumatic actuators).

8. Expert Opinion

“The Medifly PATR24 Black polyamide tube, 4×2 mm, is an uncompromising automotive standard for commercial transport. Thanks to compliance with the strict DIN 73378 requirements and a working temperature down to −60 °C, this tube is ideally suited to operation in the harsh climate conditions of Moldova and CIS countries. The black, carbon-filled PA12 polyamide guarantees the line’s durability even under constant exposure to road chemicals, oils, and UV radiation,” notes Vitali Boluchevski, Lead Engineer, Acvatron SRL, 18 years of experience.

9. FAQ

Is the PATR24 tube certified for truck pneumatic brakes? Yes, the Medifly PATR series is manufactured strictly to the requirements of the DIN 73378 and DIN 74324 standards for pneumatic brake systems.

How does the PATR24 tube differ from standard PA11/PA12? The PATR (PA12 TRUCK) series has increased density and hardness (70 ShD), an extended lower temperature threshold (down to −60 °C), and automotive-specific tolerances.

Can this tube be used for diesel fuel delivery? Yes, PA12 polyamide is chemically inert to diesel fuel, gasoline, engine oils, and brake fluids.

What’s the maximum working pressure the PATR24 can withstand? At +23 °C, working pressure is 42 bar, and burst pressure is 126 bar.