Nothing! A belleville disc spring is referred to by numerous names depending on the industry, location, etc. To eliminate this confusion, some other common names utilized throughout the industry include: belleville washer, belleville spring, cupped washer, conical spring, compression spring, disc spring, bellevilles, conical washer, and coned disc spring. Note that there are also a variety of spellings associated with many of these names. Please contact us for any questions. We hope to alleviate any confusion related to the nomenclature of belleville disc springs.

Belleville disc springs share many of the same characteristics as a general washer. Bellevilles are conical in shape and are designed to be loaded in the axial direction. The advantage of a belleville is that it provides a spring type characteristic while simultaneously acting as a washer.

The belleville spring, created in the mid 19th century, is named after Julian F. Belleville who is credited as the inventor of the belleville spring.

A popular use for the belleville spring is where heavy load requirements in restricted space is necessary. Some variables required for the design of a belleville spring include outside diameter (De), inside diameter (Di), material thickness (t), and dish height (ho). Infinitely variable spring characteristics are achievable by the arrangement of disc springs into columns stacked in series or in parallel.

Belleville springs are used in countless industries across the globe. Some examples include conveyors, heavy equipment, valves, actuators, aerospace, and military applications. Bellevilles provide increased spring force when small movement is required in a restricted space. Belleville springs can be designed to provide spring movement with constant pressure throughout the deflection period (low spring rate).

High load capacity in small spaces is not possible with ordinary coil springs. Belleville washers have the ability to achieve linear or non-linear load deflection characteristics as well as maintain high tension in bolted applications such as heavy switchgears, buspar, etc. Bellevilles can also compensate for different expansion rates in joints while maintaining required tension. Bellevilles offer flexibility in deflection and load characteristics as disc springs can be stacked in series, parallel, or any combination thereof.

Both types of springs belong in the compression spring category; however, they are very different in appearance as well as loading properties. 

• A coil spring appears as a winding piece of metal in a conical or helical form.
• Belleville springs are designed for heavy loads, typically last longer, and are tougher than coil springs.

To answer this question additional information is required. Spring life is a function of several variables including material, operating temperature and pressure, corrosion tolerance, dynamic vs. static loading, etc. Please contact one of our engineers for help with estimating belleville spring life.

There are several definitions of spring rate. One definition specifies spring rate as the amount of weight required to deflect or bend a spring one inch. A softer spring, for example, will require a reduced weight to deflect a spring one inch.

DIN is an abbreviation for Deutsches Institut für Normung which is an international standards organization based out of Germany. Typical DIN specifications in the belleville industry are DIN 2092, DIN 2093 and DIN 6796. DIN 2092 specifications are design standards while DIN 2093 are manufacturing standards. DIN 6796 provides standards for heavy duty belleville springs. Key Bellevilles adheres to DIN specifications in the manufacturing of belleville disc springs.

Torque represents the rotational force (twist) applied to a belleville disc spring. This is a useful characteristic to determine how much force is required to properly tighten a belleville disc spring. While torque is a rotational force, Flat Load refers to the axial force applied to a belleville disc spring. Both parameters are important to ensure belleville disc springs are tightened properly in different applications.

Disc loading as a function of deflection (linear & non-linear) is very important in the design of belleville disc springs. Note that % deflection and loadings are a function of many spring characteristics including dish height, inside/outside diameters, thickness, and material type. Contact one our engineers for more details related to disc loading and deflection.

Flat washers are useful when several materials are present in a given application. Since bellevilles are designed to withstand a specified loading in a given space, sometimes the material required can be significantly harder than surrounding materials. In such cases, the use of flat washers can buffer this discrepancy to provide long-lasting performance.

Fatigue life is used to describe the expected life of a disc spring under specified conditions. Load and stress must be calculated as a function of deflection to ensure fatigue does not exceed the maximum permissible stress. Contact one of our engineers for more details related to the importance of fatigue life in the design of belleville disc springs.

Key Bellevilles is ISO compliant. We believe in providing high quality products to every customer.

Key Bellevilles does not require a minimum number of parts; however, we do have a $50.00 minimum per line. However we answer our phones and are always willing to answer questions.