Locknuts Explored: The Hex Nut

Hex locknuts are among the most common locknuts used in industrial assemblies, named for their hexagonal shape. A hex profile provides installers with strong tool contact while still allowing flexibility in wrench positioning, which helps with tight or repetitive assembly work.

At Lok-Mor®, we manufacture a wide range of hexagonal locknuts for demanding applications. Our manufacturing capabilities also extend to non-hexagonal shapes for specialty applications.

Hex Locknuts Manufactured by Lok-Mor

Below are three examples of hex locknut designs we manufacture at our Texas facility, each with a different locking mechanism and built for a range of industrial applications.

• The HEX-LOC®

  • The HEX-LOC® is our standard hexagonal locknut. The threads at the center of the nut are deflected, providing a two-way locking action for a vibration-resistant connection.

• The ANCO® PN-LOC®

  • The ANCO® PN-LOC® is our proprietary structural locknut. This award-winning hex locknut features a stainless-steel ratchet pin to help ensure consistent locking torque. The extreme vibration resistance of the ANCO® PN-LOC® makes it our most popular hexagonal locknut for industrial applications.

• The O-LOC™

  • The O-LOC™ is a hexagonal locknut featuring two oval-shaped locking elements at the top of the nut. These elements create frictional thread interference during installation to withstand heavy vibration and shock.

Other Common Locknut Shapes

While hexagonal locknuts are the most common, other shapes are available for specialty applications. Below are three examples of non-hexagonal locknuts we custom-manufacture for customers at Lok-Mor®:

• Square Locknuts

  • Square locknuts provide a larger grip area for a wrench during installation. That increased contact surface can make square nuts highly resistant to loosening, but it also makes them more difficult to tighten than hex nuts.

    Square locknuts can also be useful in tight spaces: only two sides need to be gripped, making them a practical option with pliers when clearance is limited. They’re commonly paired with square-headed bolts and flat washers.

• Wing Locknuts (Butterfly Locknuts)

  • Wing locknuts, also known as butterfly locknuts, are easily identifiable by the large metal “wings” extending from the center of the nut. These locknuts are designed for easy hand installation, making them a convenient option for frequently adjusted assemblies.

    Because they’re quick to install and versatile, wing locknuts show up in a wide range of industrial and consumer applications.

• Acorn Locknuts (Cap Locknuts)

  • Acorn locknuts, also known as cap locknuts, have a domed end on one side. They’re designed to cap an exposed thread, helping protect people from sharp or protruding threads while also delivering a more finished appearance.

Finding the Right Locknut Shape

If you’re unsure which locknut shape is best for your application, the locknut experts at Lok-Mor® can help. See our complete line of free-spinning and prevailing-torque locknuts, send an email to [email protected], or contact us today to discuss your application and find the best solution.