It is placed beneath a nut to prevent it from loosening.
These specifications are outlined in national standards.
In the fields of mechanical design and manufacturing, common methods for preventing nuts (or bolts) from spontaneously loosening include:
Adding a spring washer (simple and easy to implement);
Using a castellated nut in conjunction with a cotter pin (which adds additional machining steps);
Adding a locking washer (which adds additional machining steps);
Drilling a hole through the hexagonal head of a bolt and inserting a steel wire (which adds additional machining steps).
Spring washers are utilized for anti-loosening purposes; for instance, bolts connecting an electric motor to its base typically require spring washers, as motor vibration would otherwise cause the nuts to loosen. Generally, fasteners on equipment subject to vibration are fitted with spring washers; however, flanges typically do not require them. Whether or not to use spring washers on a flange depends on the medium flowing through the pipeline; if the medium is prone to generating pulsations, it is advisable to use spring washers. Furthermore, for pipelines conveying high-velocity fluids or those with frequent changes in diameter, one should avoid applying a blanket rule. On certain valves-specifically at the packing gland flange-the use of spring washers is required; spring washers are included in the product selection database provided by KuaiYiYou Automation.
