Rilsan PA11 and PA12 tubes: differences, applications, and selection criteria

When designing a pneumatic circuit or replacing a flexible polyamide pipe, the Rilsan® brand represents a point of reference for reliability.

Behind this brand name lie two technically different materials: polyamide 11 (PA11) and polyamide 12 (PA12). Choosing one or the other is not a matter of indifference: operating temperature, chemical resistance, cold behavior, and even the origin of the raw material significantly affect the system's performance.

What is Rilsan and why is it the standard in pneumatic circuits?

Rilsan® identifies the family of polyamides used for the production of flexible hoses for pneumatic automation, braking systems and the transport of hydrocarbons or technical fluids. 

The success of these materials comes from the combination of physical properties that are difficult to find in other thermoplastics:

• High strength-to-weight ratio: maximum lightness of lines.
• Elastic memory and flexibility: Reduced bending radius without permanent deformation or kinking.
• Low coefficient of friction: minimization of pressure drops in the flow.
• Regulatory compliance: full compliance with stringent standards DIN 74324 e DIN 73378 for Automotive and Hydraulic/Pneumatic systems.

Rilsan PA11 tube: technical characteristics

Origin and composition of PA11

PA11 is a plant-based polyamide obtained from castor oil. It is a plasticized material stabilized by light and heat, with low moisture absorption. This biological origin directly affects the tube's mechanical properties, particularly its impact resistance at low temperatures.

Mechanical and chemical performance of PA11

•   Operating temperature: from -40°C to +80°C, for aqueous fluids +70°C
•   Operating pressure: from 11 to 40 bar (depending on diameter)
•   diameters: from 2 to 40 mm
•   Cold impact resistance
•   Color: Black recommended for outdoor applications
•   Compliance: DIN 74324 and DIN 73378 standards (depending on diameter)

 

Rilsan PA12 tube: technical characteristics

Origin and composition of PA12

PA12 is a polyamide with a longer molecular chain than PA11, a characteristic that gives it lower moisture absorption and superior dimensional stability over time. PA12 is also available in a wide range of colors (neutral, black, red, yellow, green, orange, and blue), useful for circuit coding in complex systems.

Mechanical and chemical performance of PA12

•   Operating temperature: from -40°C to +80°C
•   Maximum temperature: +70°C in the presence of aqueous fluids
•   Diameters: from 2 to 40 mm
•   Chemical resistance: to oils, hydrocarbons and industrial chemicals
•   Atmospheric resistance: UV and weather resistant, ideal for outdoor applications
•   Compliance: to DIN 74324 and DIN 73378 regulations based on diameters

 

PA11 vs PA12: comparison table

Parameter	Rilsan PA11 tube	Rilsan PA12 tube
Origin of raw material	Vegetable (castor oil), 100% bio-based	Mainly petrochemical
Operating temperature	From -40°C to +80°C	From -40°C to +80°C
Operating pressure	From 11 to 40 bar (depending on the diameter)	From 11 to 40 bar (depending on the diameter)
Diameter range	2 to 40 mm	2 to 40 mm
Cold impact resistance	Very high, the strong point of the PA11	Good, slightly inferior to PA11 at low temperatures
Moisture absorption	Reduced	Very low, among the lowest in the polyamide family
Chemical and hydrocarbon resistance	Good	Very high, also suitable for harsh environments
Resistance to UV rays and atmospheric agents	Good (black version recommended for outdoor use)	High, suitable for prolonged outdoor applications
Available colours	Neutral, black, red, yellow, green, orange, blue	Neutral, black, red, yellow, green, orange, blue
Reference standards	DIN 74324, DIN 73378	DIN 74324, DIN 73378
Typical uses	Pneumatic automation, braking systems, low-temperature applications	Compressed air, braking systems, chemical and external environments

 

Applications: when to choose PA11 and when to choose PA12

When to Prefer Rilsan PA11

• Low temperature environments: installations subject to frost, cold rooms or industrial machinery operating outdoors in harsh climates where mechanical fragility is the primary risk factor.
• Industrial vehicles: braking systems and auxiliary circuits exposed to strong vibrations and stone impacts.
• Low environmental impact projects: companies that require components formulated with renewable raw materials.

When to Prefer the Rilsan PA12

• High Precision Pneumatic Automation: CNC machine tools and industrial robotics where the consistency of the internal/external diameter guarantees the perfect insertion of automatic fittings over time.
• Fuel and Lubricant Transport Lines: dosing or cooling circuits exposed to prolonged contact with aggressive chemical agents.
• Continuous External Installations: pneumatic lines on building structures, naval structures or renewable energy plants exposed to direct sunlight.

 

Selection criteria: how to choose between PA11 and PA12

In practice, the selection between Rilsan PA11 and PA12 pipes depends on a combined analysis of some key system factors.

Operating temperature

If the system operates predominantly in cold environments or with highly variable temperatures, PA11 offers a greater safety margin thanks to its resistance to cold impact. For applications requiring higher operating temperatures, even with occasional peaks, PA12 represents the best performing solution.

Pressure and mechanical stress

For pneumatic circuits operating at high pressures or under continuous mechanical stress, it is essential to check the pressure table based on the chosen diameter and compare it with the actual operating parameters of the system.

Exposure to UV rays and outdoor environments

For outdoor installations or those exposed to prolonged sunlight, PA12 offers superior weather resistance, although black PA11 is also suitable for this type of use.

Sustainability and origin of the raw material

For companies that integrate sustainability criteria into their purchasing specifications, plant-based PA11 represents an option aligned with policies to reduce the footprint deriving from fossil fuels, without compromising on technical performance.

Reference standards

Both materials comply with DIN 74324 and DIN 73378 standards : however, it is always advisable to check the specific technical data sheet of the chosen pipe, in particular for the diameter, thickness and pressure class required by the system.

 

Why trust Universalflex for Rilsan pipes?

Universalflex offers a complete range of Rilsan PA11 and PA12 pipes , available in various colors and diameters, with detailed technical data sheets for each product code. Our technical support team assists customers in selecting the most suitable material based on the system's operating conditions, ensuring components comply with industry regulations and offering pre- and post-sales consultancy.

Contact Universalflex for personalized advice on choosing the Rilsan tube best suited to your application.

 

FAQ – Frequently asked questions about Rilsan PA11 and PA12 tubes

 What is the main difference between Rilsan PA11 and PA12 tubes?

The main difference concerns the origin of the raw material and the extreme temperature performance: PA11 is of plant origin and offers superior cold impact resistance, while PA12 guarantees a wider operating temperature range and slightly greater chemical resistance.

 Are the Rilsan PA11 and PA12 tubes interchangeable?

In most standard applications, yes, as both meet the same DIN standards. However, for systems with extreme operating conditions (very low or very high temperatures, heavy chemical exposure), it is advisable to check the technical specifications of the individual part number before replacing.

Which Rilsan tube should I choose for a braking system?

Both materials are used in compressed air braking systems. The choice depends on the vehicle's operating climate: for cold environments or with significant temperature variations, PA11 offers greater reliability, while for heavy-duty applications at higher temperatures, PA12 is often preferred.

 Is Rilsan PA11 tube really more sustainable than PA12?

PA11 is produced from castor oil, a renewable source, which makes it a preferable choice from the point of view of raw material sustainability compared to a polyamide of predominantly petrochemical origin, given the same technical performance required by the application.

What is the maximum pressure that a Rilsan tube can withstand?

The maximum pressure varies depending on the pipe diameter: for PA11, for example, the operating range is approximately between 11 and 40 bar. It is always necessary to refer to the technical data sheet for the specific code for correct system sizing.