Metric Zinc Plated Class 10.9 Steel Prevailing Torque Flange Nuts
Class 10.9 Metric Prevailing Torque Flange Nuts, also called flange lock nuts, all-metal locking flange nuts, stover flange nuts, or self-locking flange nuts, deliver high-strength fastening combined with reliable vibration resistance in a single, efficient component. These nuts feature an all-metal distorted thread locking mechanism and an integrated washer flange, eliminating the need for separate lock washers, flat washers, or thread locker compounds. Manufactured from Class 10.9 alloy steel with a zinc plated finish, they are engineered for demanding applications where maximum clamping force and secure, maintenance-free locking are essential.
Why Choose Class 10.9 Prevailing Torque Flange Nuts?
Class 10.9 steel provides a minimum tensile strength of 1,040 MPa (150,000 PSI) and yield strength of 940 MPa, approximately 25-30% stronger than Class 8.8 fasteners and the metric equivalent of SAE Grade 8. Combined with the all-metal prevailing torque locking feature, these nuts are purpose-built for high-stress, high-vibration environments where standard fasteners would loosen over time. The all-metal locking design withstands elevated temperatures, repeated installation cycles, and harsh operating conditions that would compromise nylon insert lock nuts. The integrated flange distributes load across a wider bearing surface, reducing stress concentration on the mating material and preventing pull-through on softer substrates like aluminum, composites, and thin sheet metal.
Material & Specifications
Our Class 10.9 metric prevailing torque flange nuts are manufactured from quenched and tempered alloy steel, heat-treated to achieve the mechanical properties required for safety-critical and heavy-duty fastening applications. The all-metal locking element is formed by mechanically distorting the thread profile at the top of the nut, creating controlled interference that generates consistent prevailing torque throughout the nut's service life. The zinc plated finish provides corrosion resistance for indoor environments and moderate outdoor exposure while meeting RoHS compliance standards for environmentally responsible manufacturing.
All-Metal Locking: Built for Demanding Environments
Unlike nylon insert lock nuts that are limited to approximately 250°F (120°C), all-metal prevailing torque nuts maintain their locking performance at elevated temperatures encountered in engine compartments, exhaust systems, industrial machinery, and other high-heat applications. The all-metal design also allows for limited reuse, typically 5 to 15 installation cycles depending on the specific nut design and application, making them more practical than single-use adhesive locking methods for equipment requiring periodic maintenance or adjustment.
Prevailing Torque Flange Nuts vs. Serrated Flange Nuts
Both prevailing torque and serrated flange nuts provide resistance to loosening, but through different mechanisms. Serrated flange nuts feature teeth on the underside of the flange that bite into the mating surface, creating mechanical resistance to rotation, but they permanently mar the surface and lose effectiveness if the joint is loosened and retightened. Prevailing torque flange nuts generate locking friction within the threads themselves, allowing the nut to be removed and reinstalled while preserving the mating surface. For applications requiring both surface protection and vibration resistance, prevailing torque flange nuts are the superior choice.
Common Applications
Class 10.9 metric prevailing torque flange nuts are specified across industries where high strength and reliable locking are mandatory:
- Automotive & Motorsports: Suspension components, drivetrain assemblies, turbocharger installations, roll cage hardware, engine mounts
- Heavy Equipment & Machinery: Hydraulic cylinder mounts, structural connections, vibrating screens, crusher assemblies
- Agricultural Equipment: Combine harvesters, tillage equipment, sprayer booms, high-vibration implements
- Industrial & Manufacturing: Compressors, pumps, motor mounts, gearboxes, process equipment subject to vibration
- Transportation & Rail: Truck chassis, trailer assemblies, railcar components, transit equipment
Available Sizes
We stock Class 10.9 metric prevailing torque flange nuts in a range of popular thread sizes to cover most heavy-duty and high-vibration applications. Albany County Fasteners offers competitive bulk pricing and same-day shipping on in-stock items to keep your projects on schedule.
Need a specific size or alternate grade? Contact our team, with over 18 million fasteners in stock, we can help you source the right locking flange nut for even the most demanding applications.