A spring washer, also known as a split washer or lock washer, is a type of fastener accessory designed to maintain tension and prevent loosening of bolts, nuts, and screws under dynamic conditions. In this blog, we will dive deeper into the purpose of a spring washer, its functionality, and the various types suited for different applications.
What is the Purpose of a Spring Washer?
The main purpose of a spring washer is to prevent fasteners from loosening due to vibrations, torque, and thermal expansion pressure. By providing constant tension, it helps maintain a secure, stable fastening joint over time.
Here’s how it works:
1. Prevent Loosening
The primary function of a spring washer is to resist the loosening of fasteners under mechanical stress. A split washer, for instance, has a helical shape and sharp, raised edges. When tightened, these edges bite into both the fastener (nut) and the material surface, creating friction that resists rotation. This friction and mechanical lock ensure the fastener stays tightly in place, even in high-vibration environments.
In contrast, a toothed lock washer (internal or external) features teeth that dig into both the fastener and the mating surface, physically preventing rotation.
2. Provide Tension
When a spring washer is tightened, it compresses and deforms, creating a spring force that holds the fastener in place. This tension is key to keeping the assembly secure, as it compensates for any minor changes in the joint. Over time, surface irregularities or minor thermal contractions may occur, but the spring washer maintains continuous pressure to ensure the fastener stays tight.
This spring force is particularly useful in high-vibration environments like machinery, automotive, and aerospace applications, where traditional flat washers would fail to provide enough tension.
3. Compensate for Surface Irregularities
A spring washer can also help mitigate the effects of surface irregularities in the mating parts. The washer’s design helps distribute the load evenly, preventing localized deformation and damage to the material. This ensures that both the fastener and surface material remain in good condition during use.
4. Reduce the Risk of Thread Stripping
By maintaining consistent pressure, spring washers help prevent the threads of the bolt or nut from backing off or becoming stripped, particularly under stress or when heavy loads are applied. This increases the overall reliability of the fastened joint.
Types of Spring Washers and Their Specific Purposes
1. Split Lock Washer
Purpose: Designed to provide frictional resistance and maintain load/tension, split washers prevent loosening from vibrations.
Applications: General industrial, automotive, and construction.
2. Toothed Lock Washer
Purpose: Offers higher rotational resistance due to the teeth that lock mechanically into the mating surface.
Applications: Commonly used on softer materials like plastic or aluminum, or in small electrical screw connections.
3. Wavy Washer
Purpose: Functions as a lightweight spring to absorb shock and maintain load in low-load or constant applications.
Applications: Bearings, low-load applications, or as a spacer to remove axial play.
4. Curved Washer
Purpose: Similar to the wavy washer, but designed to apply continuous light spring force over small deflections.
Applications: Electrical connections and low-force assemblies.
Conclusion: Why Choose a Spring Washer?
While flat washers are used to distribute load evenly, spring washers actively work to maintain clamping force and resist the forces that could cause a bolted joint to fail. By offering a combination of tension, friction, and load distribution, spring washers are essential in high-stress applications, offering long-term durability and stability.
Available in various materials like stainless steel for corrosion resistance or hardened steel for heavy-duty use, spring washers are versatile and can be used in many industries, including automotive, construction, marine, and industrial machinery.
Looking for durable spring washers? Tianqi offers a variety of high-quality split washers, lock washers, and more for your automotive, construction, and industrial needs. Contact us today to learn more or place your order for reliable, long-lasting solutions!
