Single Tab Lock Washer

A bladed lock washer is a kind of gasket that prevents thread connection from becoming loose or elastic deformation through mechanical structure. Its core function is to provide durable locking force for fasteners while also reducing vibration, compensating effect and ensuring joint stability. Details of its features and design principles are given below:
1.Core functions: Anti-Loosening, cushioning, compensation.
Anti-Loosening Function
Mechanical interlocking or elastic deformation counteracts thread loosening caused by vibration and impact. For example, a dual-stack self-locking washing machine consists of two serrated washers. During installation process, the larger tooth surfaces are in contact with each other and the smaller tooth surfaces are in contact with nut and the fastener respectively. When vibrations occur, the larger tooth surfaces moves upward, locking the bolt with a diagonal difference (alpha > bolt thread angle β) to prevent loosening.
Externally toothed lock washers uses their outer serrations to touch the fastener surface, increasing friction and preventing the nut from backing out.
Vibration Cushioning
Spring gasket or elastic lock washers absorbs vibration energy through their own elastic deformation, reduces the impact of load on the connection and protects the fastener surface from damage. Closing the gap
Fill gaps in joints due to material fatigue, temperature fluctuations, or prolonged use to prevent fasteners from loosening due to gap expansion.
ii. Design Principle: Mechanical Interlocking and Elastic Deformation
Mechanical Interlocking Type
Double-stack self-locking gaskets, such as the NORD-LOCK series, utilize tooth structure to produce permanent elastic deformation under preload, resulting in self-reinforcing locking. Experimental data shows that its anti-loosening ability is more than 4 times that of conventional solution. Even at extreme temperatures of -50°C to +300°C, the pre-load loss rate is below 3%.
External Tooth Lock Washers: External fixed gasket embedded in the nut or fastener material, with a strong resistance to loosening. Suitable for high anti-skid performance.
Elastic Deformation Type
Spring Washers: Spiral ring with incision creates spring action during tightening, increasing friction and counteracting loosening forces in threaded connections. Note, however, that their anti-loosening effectiveness is limited in high-strength bolt connections, which may lead to a decrease in clamping force. Wedge self-locking gaskets, such as the NL30 series, use an interlocking wedge-shaped bevels when tightening bolts for a a directional wedging effect. This elastic deformation converts the tension of the bolt into frictional resistance, maintaining a steady pretension.
III. Typical Application Scenarios
High-Vibration Environments
In the aerospace and automotive industries, threaded connections in engines and transmission systems can be affected by severe vibration over time. Double-stacked or wedge-shaped self-locking gaskets can significantly improve connection durability and prevent loosening risks.
Dynamic Load Scenarios
Parts such as rail transit bogies and wind turbine tower flanges must be able to withstand alternating loads and temperature fluctuations. The locking gasket maintains the preset clamping force through dynamic compensation to ensure safe operation of the equipment.
Corrosive Media Environments
In marine engineering and chemical equipment, lock washers can prevent corrosion caused by environmental factors and prolong the service life of joints. For example, steel lock are suitable for humid or salt spray environments. IV. INTRODUCTION Selection Recommendations
Selection based on Vibration Frequency
For high frequency vibration applications such as aerospace, double stack self-locking gaskets or wedge self-locking gaskets are preferred. Its mechanical interlocking structure has high reliability.
For low frequency vibration applications such as construction machinery, externally toothed lock washers or spring gaskets can be used to balance cost and performance.
Load Type
For dynamic loads,such as alternating stresses, choose gaskets with elastic compensation capabilities, such as the NORD-LOCK series.
For static loads (such as mounting brackets), a combination of common spring gaskets or flat gaskets can be used to reduce costs.
Selection based on environmental conditions
Verify the thermal expansion coefficient of the washer material at high or low temperatures to prevent preload loss due to temperature variations.
For corrosive environments, stainless steel or galvanized gaskets should be selected to prevent rust from affecting loose performance.