Lock washers and spring lock washers are both types of washers used in fastening applications, but they have distinct designs and functions:
Lock Washer: A lock washer is a type of flat washer with a split or bent design that provides tension to prevent fasteners (like bolts and nuts) from loosening due to vibrations or other forces. There are two common types of lock washers:
Split Lock Washer: This is a flat washer with a split cut that creates a slight overlap. When the washer is installed between the nut and the mating surface, the spring tension between the split ends creates a locking effect. It helps resist loosening caused by vibrations but may not be as effective in certain situations where there are extreme vibrations or constant movement.
Toothed Lock Washer: This type of lock washer has teeth or serrations on one side. When installed, the teeth bite into the mating surface and the fastener head/nut, creating friction that resists rotation and loosening.
Spring Lock Washer: A spring lock washer, also known as a helical spring washer or split spring washer, is a washer made from a circular piece of metal with a gap or split cut, forming a helix-like shape. When a fastener is tightened against the spring washer, it compresses and exerts spring pressure, creating tension that helps prevent the nut or bolt from loosening due to vibrations.
The main difference between a standard lock washer and a spring lock washer lies in their designs and the way they create tension:
- Standard lock washers (like split lock washers and toothed lock washers) use the bending or biting of the washer itself to create tension.
- Spring lock washers use the spring action of the helix shape to generate tension.
Spring lock washers are generally considered more effective than standard lock washers for resisting loosening caused by vibration. They provide more consistent tension and are less likely to relax over time. However, it's important to note that in critical applications or when dealing with high vibrations, more advanced fastening methods like using lock nuts or adhesives may be required to ensure a secure joint.
In many industrial and engineering applications today, other fastening methods like nylon-insert lock nuts or thread-locking adhesives are preferred over lock washers and spring lock washers due to their more reliable performance and ease of use.