As a leading manufacturer of Made-in-America™ locknuts, we are frequently approached by engineers and procurement personnel seeking to determine if locknuts can be reused. To help answer these questions, our locknut experts have written this blog, explaining reusable locknuts, their common applications, and how they differ from single-use locknuts.
Reusability depends on the locknut design, installation method, and whether the locking feature has worn or permanently deformed.
In general, many free-spinning locknuts can be reused because they turn freely on the bolt during installation before being tightened into place. Unlike prevailing-torque locknuts, which deform around the bolt threads during installation for a superior lock, free-spinning locknuts can be quickly installed, adjusted, and reused.
Examples of Reusable Locknuts
The design of free-spinning locknuts varies to meet the requirements of specific applications. At Lok-Mor®, we manufacture five types of free-spinning locknuts, four of which are reusable:
- The DBL-LOC®
- The DBL-LOC® is our self-sealing option. The nylon insert in the base of this locknut deforms when tightened, creating a secure seal against moisture and other contaminants. Ideal for electrical applications.
- The DRAKE™
- This locknut is divided into two pieces: a top nut and a bottom nut. When tightened together, the two pieces create a wedging action for a powerful lock. This innovative design allows the DRAKE™ to be positioned anywhere along the threaded part.
- The MAR-LOC™
- The MAR-LOC™ is a self-locking, Marsden-type locknut, featuring vertical slats that deform around the threading when tightened. Ideal for vibratory automotive applications.
- The SPN-LOC®
- The SPN-LOC® features serrated locking elements that engage with the mating surface during tightening, preventing it from loosening under vibration or dynamic loads.
Some of the prevailing-torque locknuts we manufacture at Lok-Mor® are also reusable. Our standard nylon-insert locknut, the N-LOC™, can be reused several times, as can our flex locknut, the FLEX-LOC™. Although these prevailing-torque locknuts can be reused, they gradually lose their locking effectiveness with each use. For more information about reusable prevailing-torque locknuts, please contact a Lok-Mor™ expert.
Unlike free-spinning locknuts, which are designed for easy installation and reusability, prevailing-torque locknuts provide exceptional locking strength by creating constant frictional resistance between the threads and the bolt. This frictional resistance results from metal threads deforming into bolt threads. For nylon-insert locknuts, a polymer piece deforms into the bolt threads instead.
An important note on prevailing-torque locknuts is that, due to the deformation, they are not typically designed to be loosened or reused.
Applications for Free-Spinning and Reusable Locknuts
The design of free-spinning locknuts enables them to rotate freely on the bolt before the locking mechanism is engaged. These locknuts, which can often be reused multiple times, are well-suited for applications that require quick installation and possible readjustments. Free-spinning locknuts are the versatile choice, ideal for applications such as:
- Automotive – Our free-spinning options can secure components subjected to constant vibration. In the case of the DBL-LOC®, the nylon insert creates a protective seal against moisture, mud, and dust.
- Machinery and Equipment – Free-spinning locknuts offer powerful vibration resistance under dynamic forces.
- Oil & Gas – Free-spinning locknuts like the DRAKE™ provide superior holding power to ensure the integrity of threaded assemblies.
A Brief Summary of Reusable Locknuts
Not all locknuts are reusable, but most types of free-spinning locknuts can be used multiple times. Free-spinning locknuts are the versatile choice: offering fast installation, adjustability, and reusability. While prevailing-torque locknuts offer unmatched locking power, the versatility of free-spinning locknuts makes them ideal for vibratory applications.
There are many types of free-spinning locknuts, each specialized for specific applications. Interested in which free-spinning locknut is best for your application? Browse our complete line of free-spinning locknuts or contact a Lok-Mor® expert today by visiting our contact page.
