Why thread locking matters

Thread locking methods: Nyloc, spring washers, WEICONLOCK® 

Fastener loosening is a leading cause of mechanical failure, especially in vibration-heavy environments like mining, transport, and heavy machinery.

Using the right thread locking method improves safety, reliability, and reduces rework.

1. Nyloc nuts

Nyloc  (nylon insert) nuts include a polymer collar that grips the bolt thread.

Pros:

  • Reusable several times
  • Simple to install
  • Resistant to vibration

Cons:

  • Heat sensitive (limit ~120°C)
  • Not suitable for permanent locking

Best for: Automotive, machinery, light structural

2. Spring washers

Split or helical  spring washers provide tension to resist rotation.

Pros:

  • Inexpensive and widely available
  • Easy to use

Cons:

  • Limited effectiveness under heavy vibration
  • May flatten over time

Best for: General-purpose fastening, where moderate resistance is acceptable

3. Lock washers

 

Lock washers  are designed to prevent loosening by applying spring tension or biting into the mating surfaces. Common types include internal/external tooth and conical (Belleville) washers.

Pros:

·         Provide mechanical resistance to loosening

·         Suitable for both rotational and axial loads

·         Simple to install

Cons:

·         Limited reuse depending on type

·         Can damage softer surfaces

Best for: Electrical assemblies, light mechanical applications, vibration-prone joints

4. Chemical threadlockers (e.g. WEICONLOCK®)

Anaerobic adhesives  applied to threads to bond mating surfaces.

Pros:

  • Highly effective
  • Available in various strengths (removable to permanent)
  • Seals threads from moisture

Cons:

  • Requires curing time
  • Some grades require heat to remove

Best for: Critical machinery, rotating parts, metal-to-metal fastening

5. Distorted thread locknuts

Deformed at the top or side to create interference with the bolt thread.

Pros:

  • No nylon or chemical needed
  • High-temperature resistance

Cons:

  • Not reusable (in most cases)
  • Requires more torque to install

Best for: Rail, mining, heavy-duty equipment

Choosing the right method

When selecting a thread locking solution, consider:

  • Vibration level
  • Temperature range
  • Maintenance needs
  • Reusability

Tip: Combine methods for critical applications

In some cases, combining a nyloc nut with WEICONLOCK®, or a spring washer with a distorted nut, can improve reliability.

 

Want help locking down your fasteners? Explore our full range of locking solutions or talk to our team for expert advice 1300 580 954.