DIN 7967 Self-Locking Counter Nuts (PAL Nuts)
Manufactured in accordance with DIN 7967, Self-Locking Counter Nuts (commonly known as PAL Nuts) are a specialized type of prevailing-torque locknut. They are distinguished by their castellated, wing-like flanges which provide a secure mechanical locking action. Primarily designed as a secondary locking element (jam nut), they are installed over a primary hex nut, where their flanges deflect and grip the sides of the nut to prevent rotation. They are also suitable as standalone fasteners in light-duty, low-torque applications.
This component serves a dual purpose as both a primary fastener and a secondary lock, offering a simple and reusable vibration-resistant solution.
Primary Function (Secondary Locking Nut): The most common application is to secure a standard hex nut (primary nut) in place. When tightened against the primary nut, the spring-steel flanges of the PAL nut are deflected inwards, applying a continuous clamping force against the flat sides of the hex nut. This creates a strong frictional and mechanical lock that resists loosening caused by vibration.
Secondary Function (Standalone Nut): In non-critical, low-stress assemblies, PAL nuts can be threaded directly onto a screw or bolt and tightened by hand or with a spanner. The flanges provide some locking action against the mating surface.
Reusable: Can be installed and removed multiple times without significant loss of locking performance.
No Thread Damage: Unlike nylon insert nuts, the locking action is external and does not affect or wear the bolt threads.
Installation: A specific spanner or adjustable wrench is required to engage the flanges during tightening.
Torque Limitation: Not designed for high torque applications. The primary use is for locking, not for providing high clamping force.
The choice of material determines the nut’s corrosion resistance and suitability for different environments.
Material |
Key Characteristics |
Ideal Application |
Considerations |
| Carbon Steel | Economical, high strength. Typically supplied plain or with a basic protective coating. | General industrial use in dry, indoor environments where corrosion is not a concern. | Will rust if exposed to moisture. Often used with a supplementary corrosion-resistant finish. |
| Stainless Steel A2 (18-8) | Good corrosion resistance, protects against rust from water and mild chemicals. | The standard choice for most applications requiring durability outdoors or in damp conditions (e.g., machinery, furniture, general construction). | Offers the best balance of performance and cost for general-purpose corrosion resistance. |
| Stainless Steel A4 (316) | Excellent corrosion resistance, superior to A2 grade. Withstands harsh weather, salt spray, and many chemicals. | Demanding environments such as marine/coastal applications, chemical processing, food industry, and other highly corrosive settings. | Premium material for maximum service life in aggressive conditions. |
| CLICK VIEW ONLIN | DIN 7967 Dimensions | DIN 7967 weight chart |
| CLICK DOWNLOAD | DIN 7967 Dimensions pdf | DIN 7967 weight chart pdf |
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PIC |
PRODUCT |
SIZE |
GRADE |
FINISH |
THREAD |
|
|
Self Locking Counter / PAL Nuts (DIN 7967) - Stainless Steel (A2) |
M6-M30 |
A2 Grade |
Natural |
Coarse |
|
|
Self Locking Counter / PAL Nuts (DIN 7967) - Marine Stainless Steel (A4) |
M6-M30 |
A4 Grade |
Natural |
Coarse |
|
|
PAL Self-locking counter nut DIN 7967 Spring steel Zinc plated |
M6-M20 |
Grade |
Zinc CR3 |
Coarse |
