Product Overview
The Festo PUN-H-4x0.75-RT-25 (part number 8204445) is a red polyurethane tubing engineered for demanding pneumatic applications. With an outside diameter of 4 mm and an inside diameter of 2.6 mm, this tubing is designed to deliver reliable compressed air supply while maintaining high flexibility and kink resistance. Its material composition, TPE-U (PU) with an ether base, provides hydrolysis resistance, making it suitable for environments with high moisture levels, including wet areas and food industry applications. The tubing is also certified by the German Technical Control Board (TÜV) under certificate B 013277 0506 00, ensuring compliance with rigorous quality standards.
Technical Specifications and Performance
The PUN-H-4x0.75-RT-25 operates within a broad ambient temperature range of -35°C to 60°C. It supports an operating pressure of -13.775 psi to 87 psi across the entire temperature range, with a temperature-dependent operating pressure extending up to 145 psi. For water applications, the maximum pressure is 0.3 MPa at 0-60°C, as indicated in the technical documentation. The tubing has a minimum bending radius of 8 mm and a bending radius relevant for flow rate of 16 mm, allowing for compact routing in tight spaces. Its suitability for energy chains makes it an excellent choice for dynamic applications where continuous motion is required.
Material and Compliance
The tubing is made from TPE-U (PU) with a Shore hardness of D 52 +/-3, offering a balance of flexibility and durability. It is RoHS-compliant and meets LABS (PWIS) conformity per VDMA24364-B2-L, ensuring it is free from materials that could affect paint adhesion. The material fire test rating is UL94 HB, indicating a horizontal burn test classification. For use in the food industry, supplementary material information is available, and the tubing is suitable for the production of Li-ion batteries, with restrictions on metals containing more than 1% copper, zinc, or nickel, except for specific exceptions like nickel in steel and chemically nickel-plated surfaces. The cleanroom class is noted as statically installed element, with no meaningful evaluation possible according to ISO 14644-1.
Installation and Connectivity
The PUN-H-4x0.75-RT-25 is designed for plug connections with an outside diameter of 4 mm, and it is compatible with barbed fittings having an inside diameter of 3 mm with a union nut. This compatibility ensures easy integration with Festo's QS push-in fittings, which enable quick and secure installation without the need for additional tools. The tubing's flexibility and kink resistance simplify routing in complex systems, reducing the risk of flow restrictions and minimizing downtime during installation or maintenance.
Application Considerations
This tubing is particularly well-suited for applications where moisture resistance is critical, such as in food processing, packaging, and wet environments. Its UV resistance in the black version (though this is the red version, the material inherently offers good resistance) and transparency options (not applicable to this red version) are additional features to consider when selecting tubing for specific needs. The operating medium includes compressed air as per ISO 8573-1:2010 [7:-:-] and water (liquid, ice-free), expanding its versatility. With a product weight of 0.0085 kg/m, it is lightweight and easy to handle. When integrating this tubing, engineers should verify pressure and temperature compatibility with their specific system requirements, as well as ensure proper fitting selection to maintain a leak-free connection.