Washers are thin plates, typically disk-shaped, with a hole in the center, used to distribute the load of a threaded fastener such as a bolt or nut. They are placed between the fastener and the surface of the material being fastened to prevent damage to the material and to ensure a more even distribution of the load.
Washers are typically made from metal or plastic, with metal washers being more common in industrial applications due to their durability and strength. They can also be made from other materials such as rubber or fiber for specific applications where electrical insulation or corrosion resistance is required.
Flat washers are the most common type and are used to create a larger surface area under the fastener head or nut, reducing the pressure on the material being fastened. Spring washers, also known as Belleville washers, are conical washers that provide a spring-like action, maintaining tension and preventing loosening of the fastener due to vibration or thermal expansion.
