Polyether ether ketone, widely known by the acronym PEEK, is one of the most capable thermoplastics available to engineers and manufacturers. Among the various stock shapes produced from this high-temperature polymer, PEEK rods stand out for their exceptional combination of mechanical strength, chemical resistance, dimensional stability, and thermal performance. At Kaxite Sealing, we supply PEEK rods in a range of diameters, lengths, and grades to support demanding industries such as oil and gas, aerospace, medical device manufacturing, semiconductor processing, and food packaging.
PEEK rods are frequently selected as a replacement for metal components where weight reduction, corrosion resistance, or electrical insulation is required. The material maintains its mechanical properties at elevated temperatures that would soften or degrade most other plastics. It also exhibits excellent wear resistance and a low coefficient of friction, making it suitable for bushings, seals, valve seats, and precision machined parts.
Because PEEK is a semi-crystalline thermoplastic, it offers a unique balance of toughness and rigidity. Its chemical structure provides resistance to a broad range of organic and inorganic chemicals, including steam, hot water, fuels, hydraulic fluids, and many acids. This performance profile allows PEEK rods to operate reliably in environments that are too aggressive for nylon, acetal, or PTFE in load-bearing applications.
Selecting the right rod material is a key decision in the design of machined plastic parts. PEEK rods offer several engineering advantages that are difficult to match with other polymers:
Kaxite Sealing offers PEEK rods in standard and custom sizes. The table below summarizes the most commonly ordered diameter and length combinations. We also supply cut-to-length rods and large-diameter rounds for specialized applications.
| Diameter Range | Standard Length | Diameter Tolerance | Typical Availability |
|---|---|---|---|
| 5 mm – 15 mm | 1000 mm / 3000 mm | +0.2 / -0.1 mm | Natural, black |
| 16 mm – 30 mm | 1000 mm / 3000 mm | +0.3 / -0.2 mm | Natural, black |
| 31 mm – 50 mm | 1000 mm / 3000 mm | +0.5 / -0.3 mm | Natural, black |
| 51 mm – 80 mm | 1000 mm / 2000 mm | +0.8 / -0.5 mm | Natural, black |
| 81 mm – 120 mm | 1000 mm / 2000 mm | +1.0 / -0.5 mm | Natural, black |
| 121 mm – 200 mm | 500 mm / 1000 mm | +1.5 / -0.8 mm | Natural, black, custom |
Custom diameters up to 250 mm and custom lengths up to 3000 mm can be produced on request. For high-volume programs, Kaxite Sealing can extrude or compression mold rods to specific diameter tolerances and length requirements, reducing machining waste and total cost.
The typical physical properties of unfilled PEEK rod are listed below. Actual values may vary slightly depending on the specific grade, processing method, and test standard. For filled grades such as glass-filled or carbon-filled PEEK, modulus and creep resistance increase, while elongation at break decreases.
For applications requiring higher stiffness, lower thermal expansion, or improved wear behavior, Kaxite Sealing supplies glass-filled, carbon-filled, and bearing-grade PEEK rods. These modified grades offer a useful combination of performance and machinability for structural and dynamic components.
Different service conditions call for different PEEK formulations. The most common rod grades stocked by Kaxite Sealing include:
PEEK rods are machined into a wide variety of high-performance components. Their ability to replace metals in many environments makes them valuable across numerous industries.
Although PEEK rods machine well with standard metalworking equipment, the material’s high performance depends on proper processing. PEEK is softer than metal and more thermally insulating, so heat generated during cutting can cause localized softening, smearing, or dimensional change if not managed correctly.
Kaxite Sealing can supply PEEK rods with saw-cut or machined ends, centerless-ground diameters, and specific surface finishes to reduce your in-house preparation time.
Every production lot of PEEK rods supplied by Kaxite Sealing is traceable to the raw material batch. We provide material certifications and test reports on request. Our rods are manufactured from virgin PEEK resin, and we can supply the following compliance documentation:
In addition to standard quality checks on diameter, ovality, straightness, and visual appearance, we can arrange independent third-party testing for tensile strength, density, crystallinity, and chemical composition on request.
What is the maximum continuous operating temperature for PEEK rods?
Unfilled PEEK rods can operate continuously at temperatures up to 260°C (500°F). The material retains significant strength and stiffness at this temperature, but the allowable stress decreases as temperature rises. Short-term exposure to temperatures near the melting point of 343°C is possible only for very brief periods and with minimal load. For long-term service above 200°C, glass-filled or carbon-filled PEEK grades often provide better dimensional stability and creep resistance.
Can PEEK rods be used in contact with food or inside the human body?
Yes. Unfilled natural PEEK rods are available in grades that comply with FDA 21 CFR 177.2415 for repeated food contact and USP Class VI for medical applications requiring patient contact. PEEK is also covered by ISO 10993 for biocompatibility. The material withstands repeated steam autoclave sterilization at 134°C and can be cleaned with aggressive chemical disinfectants without significant degradation. Always confirm the specific regulatory approval with Kaxite Sealing for your intended use.
How do PEEK rods compare to metal rods in terms of strength and weight?
PEEK rods have a tensile strength roughly equivalent to some aluminum alloys but at about one-fifth the weight of steel and about half the weight of aluminum. The specific strength of PEEK is therefore competitive with many metals. However, PEEK has a much lower modulus than steel or titanium, meaning it is less stiff and will deflect more under the same load. In many applications, the corrosion resistance, electrical insulation, and self-lubricating behavior of PEEK outweigh the lower absolute stiffness.
Are PEEK rods resistant to acids and solvents?
PEEK rods offer excellent resistance to a wide range of chemicals, including many acids, bases, fuels, oils, hydraulic fluids, and solvents. PEEK is not recommended for continuous exposure to concentrated sulfuric acid, concentrated nitric acid, or certain halogenated solvents at elevated temperatures. For any critical chemical environment, Kaxite Sealing recommends compatibility testing under actual service conditions, including temperature, concentration, and stress level.
What is the difference between natural PEEK rods and black PEEK rods?
Natural PEEK rods are unfilled and have a beige or tan appearance. They offer the highest elongation, best purity, and are typically specified for medical, pharmaceutical, and food-contact applications. Black PEEK rods contain carbon black or other additives that provide UV resistance and a consistent black color. The mechanical properties of standard black PEEK are generally similar to natural PEEK, but the black grade is often chosen for electronic and semiconductor applications where light reflection or static dissipation must be controlled.
Can PEEK rods be machined into complex parts with tight tolerances?
Yes. PEEK rods machine well using standard CNC lathes and milling machines. With sharp tooling, proper coolant, and controlled cutting parameters, tolerances of ±0.025 mm (±0.001 in) are achievable on many features. Because PEEK has a higher coefficient of thermal expansion than metals, parts that must hold tight tolerances over a wide temperature range should be designed with thermal effects in mind and may require stress-relieving before final machining.
What sizes of PEEK rods does Kaxite Sealing stock?
Kaxite Sealing offers PEEK rods in diameters from 5 mm to 200 mm as standard stock items. Standard lengths are 1000 mm and 3000 mm for smaller diameters, and 500 mm to 1000 mm for larger diameters. Custom diameters up to 250 mm and custom lengths up to 3000 mm can be manufactured on request. Cut-to-length pieces and machined rod ends are also available for production programs.
Kaxite Sealing provides PEEK rods with full material traceability, testing documentation, and technical guidance for material selection and machining. If you need a specific grade, diameter, length, or compliance requirement not listed above, our engineering team can assist with sourcing, custom extrusion, or alternative high-performance polymer recommendations. Contact Kaxite Sealing with your part drawings, tolerances, and operating conditions for a quotation and delivery schedule.
