13-1 OVERVIEW

Spring washers, even though small in size, may sometimes outperform much larger springs. They are used in offset situations, to provide tension in bolted assemblies, or to furnish the recoil action of springs. Even though their span of deflection is limited because of their size and especially because of their height, a somewhat improved performance may be expected where coupling several washers together. Their stackability, along with their compactibility and versatility, makes spring washers quite advantageous where used in confined spaces or where a stabilizing function is needed.

In bolted assemblies, spring washers are capable of keeping all parts under tension, preventing threaded items from rotating and loosening up. Spring washers can negate the effects of vibration, they can diminish the side-acting force and control the pressure in vibration mounts, aside from many other applications, where their usage is often taken for granted.

Basically, there are three types of spring washers:

• Cylindrically curved washers

• Wave washers

• Conical disks, or Belleville washers

These three basic variations are capable of covering a wide range of loading applications. Where cylindrically curved washers will sustain a loading of several ounces, the sturdiness of Belleville washers allows for loads ranging within tons (Table 13-1).

Table 13-1: Characteristics of Three Basic Types of Spring Washers

The effect of loading force is localized in spring washers, which causes a stress response within a small area surrounding the inside diameter of the part. The subsequent deformation tends to increase the affected area in...