Lock Nuts vs Lock Washers – Advantages and Disadvantages

Lock Nuts vs Lock Washers

Regarding fastening two components together, bolts and screws are common choices. However, to ensure the joint remains tightly secured, it’s essential to have additional elements that prevent loosening under vibration or constant use. Two popular options are lock nuts and lock washers, each with unique advantages and disadvantages. This article explores the differences between lock nuts and lock washers and helps you decide which is best for your application.

What is Lock Nuts?

A lock nut is a type of fastener with a nylon insert that grips onto the bolt threads or screw. When the nut is tightened, the nylon insert grips the threads tightly, preventing the nut from loosening under vibration or loads. It eliminates the need for additional locking elements, such as lock washers or thread-locking compounds, saving time and cost.

Advantages of Lock Nuts

One of the main advantages of using lock nuts is that they remain tight even after multiple cycles of tightening and loosening. They are reusable and do not require replacement except when damaged. Another advantage is the high degree of locking performance. The nylon insert provides a positive grip on the threads, preventing loosening under high loads or vibrations.

Disadvantages of Lock Nuts

However, lock nuts may not be effective in high-temperature environments or those with chemical exposure. The nylon insert may become brittle or swell, leading to reduced locking performance. Additionally, lock nuts require accurate torque values to apply the required pre-load on the bolt or screw. Over-tightening can damage the nylon insert, while under-tightening can result in insufficient clamping force.

What are Lock Washers?

A lock washer is a type of washer that has a spring-like shape. When a bolt or screw is tightened, the lock washer compresses and provides additional force, creating resistance against loosening under vibration or load. Lock washers come in different types, including split, toothed, and helical.

Advantages of Lock Washers

Lock washers are versatile and can be used in various environments and temperatures. They do not rely on torque values and can be used with any fastener. Lock washers are also cost-effective, readily available, and easy to install.

Disadvantages of Lock Washers

However, lock washers may have reduced effectiveness in preventing loosening under severe loads or vibrations. They may also damage the surface of the mating components or bolt head. Lock washers are also not reusable and require replacement after each use.


Both lock nuts and lock washers have their unique advantages and disadvantages. The choice between the two depends on the application and the particular requirements. Lock nuts are better if you need high locking performance and accuracy. However, if cost-effectiveness, versatility, and ease of use are essential, lock washers may serve the purpose. It’s also worth noting that alternatives to locking nuts and lock washers, such as thread locking compounds, provide higher locking performance than either individually. Reviewing the specific application requirements before making a final decision is essential.

Leave a Reply

Your email address will not be published. Required fields are marked *