Product Overview
The Festo PUN-H-4x0.75-SW-25 (part number 8205515) is a polyurethane-based pneumatic tubing engineered for demanding applications where flexibility, moisture resistance, and reliable performance are critical. With an outside diameter of 4 mm and an inside diameter of 2.6 mm, this black tubing is designed for use with push-in fittings QS and barbed fittings, making it a versatile choice for automated systems, packaging lines, and food processing equipment.
Key Material and Performance Characteristics
The tubing is made from TPE-U (PU) with an ether base, which provides excellent hydrolysis resistance—meaning it will not crack or degrade in high-moisture environments. This is particularly important for applications involving water contact up to 50°C, as the tubing can handle water as an operating medium (liquid, ice-free) in addition to compressed air per ISO 8573-1:2010 [7:-:-]. The material also meets UL94 HB fire safety standards and is RoHS-compliant, ensuring it aligns with common industrial and environmental requirements.
For engineers concerned about system integrity, the tubing's transparency (in other versions) aids in detecting particles or moisture, but this black version offers UV resistance, making it suitable for outdoor installations where sunlight exposure is a factor. The Shore hardness of D 52 +/-3 indicates a balance between flexibility and durability, allowing for a minimum bending radius of 8 mm (or 16 mm when considering flow rate), which facilitates routing in tight spaces without kinking.
Pressure and Temperature Ratings
The PUN-H-4x0.75-SW-25 operates across a wide ambient temperature range of -35°C to 60°C. Its operating pressure varies with temperature: for the entire temperature range, it is rated from -13.775 psi to 87 psi, while temperature-dependent operating pressure extends up to 145 psi. For water applications, the maximum pressure is 0.3 MPa at 0-60°C, as indicated in the manufacturer's diagram. These ratings make the tubing suitable for both standard pneumatic circuits and specialized wet-area processes, but always verify pressure limits against your specific operating conditions.
Compliance and Suitability for Specialized Industries
This tubing holds a TÜV certification (certificate number B 013277 0506 00), underscoring its quality and safety. It is also LABS (PWIS) conformant to VDMA24364-B2-L, which is essential for paint and coating applications where silicone-free materials are required. For the food industry, the tubing is noted as suitable, though you should consult the supplementary material information for specific food-contact compliance details.
In lithium-ion battery production, the tubing meets the requirement that metals with more than 1% copper, zinc, or nickel are excluded, except for specific exceptions like nickel in steel or electrical connectors—making it a viable option in that sector. Additionally, the tubing is suitable for energy chains, indicating good flexural fatigue resistance for moving applications.
Installation and Integration Benefits
From a practical standpoint, the PUN-H-4x0.75-SW-25 is designed for quick and easy installation with push-in fittings QS, reducing assembly time compared to threaded or clamped connections. Its compatibility with both plug connections (4 mm outside diameter) and barbed fittings (3 mm inside diameter with union nut) offers flexibility in system design. The lightweight profile (0.0085 kg/m) minimizes added mass to moving parts, which is beneficial for high-speed automation.
For procurement teams, this tubing's compliance with cleanroom standards (though statically installed elements may not have meaningful ISO 14644-1 classification) and its broad operating envelope make it a dependable choice for multiple lines, reducing the need for multiple SKUs. Always confirm that your operating pressure, temperature, and media compatibility align with the specifications provided to ensure optimal performance and longevity.