Belleville washers are a type of spring washer that has a conical shape. They are designed to provide a high load capacity in a compact space, making them ideal for applications where traditional flat washers may not fit. Their unique shape allows them to maintain tension and absorb shock, which helps prevent loosening in bolted connections. These washers are commonly used in various industries, including automotive, aerospace, and manufacturing. They can be stacked to achieve different spring rates and are often used in assemblies that experience vibration or thermal expansion, ensuring a secure and reliable connection over time.