Thread-locking fasteners are not new. They have been used in countless products in all industries in the quest to keep component assemblies together during their life. This article first examines three thread-locking solutions commonly used today. Each of these solutions has
performance compromises, which are outlined below.
1. All Metal Locking Screws
- Lower tension performance due to reduced stress area for some designs
- Failure modes not consistent with industry requirements
- Extended depth of engagement required to eliminate stripping of the nut member for some designs
- Non-standard nut members required for some designs
- Locking feature positional, not allowing for usage in multiple locations for some designs
- Cross-threading during assembly
2. All Metal Lock Nuts – Crimped or Indented
- Some designs suffer from inconsistent performance
- Additional manufacturing steps to produce adds cost
3. Patches and Adhesives
- Performance can be inconsistent
- Cost disadvantage
- Application is an added process for the fastener manufacturer which can lead to longer lead times and quality issues
- Inconsistencies due to interaction of locking compound and fastener finish
- “Shelf Life” concerns
- Locking feature positional not allowing for usage in multiple locations
In many cases these compromises are overcome by the advantages of thread-locking fasteners which provide:
- Cost savings
- Less complex assembly, as patches, adhesives, lock washers, lock nuts are eliminated
- Performance in high-heat or chemical-active environments that can degrade chemical locking solutions
POWERLOK® II™ fasteners are the newest evolution of the original POWERLOK® fastener. This new design eliminates compromises and provides consistent, reliable and reusable performance.
- Torque/Tension performance similar to standard machine screw and nut assemblies
- Exceptional grounding performance due to interference in the root of the nut member
- Controlled failure mode of fastener fracture in standard depths of engagement
- No changes to the standard fastening practice
- Standard nut member threads no special sizing or configuration
- Consistent performance
- Unlike chemical patches or adhesives there are no “shelf life” concerns
- No inconsistencies due to interaction of locking compound and fastener finish
- There are no positional considerations. The locking feature is throughout the full length of the thread. One common fastener can be used in multiple applications.
- POWERLOK® II™ fasteners are inherently cross-thread resistant. There is no need to hand-start fasteners or add other anti-cross threading features.
POWERLOK® II™ fasteners create cost savings without compromising assembly quality.