Wave Springs Improve Mechanical Seal Design

Mechanical seals are used for the sealing of rotating shafts against a stationary housing, such as pumps and agitators. The “stationary” part of the seal is usually located at the housing. The “rotating” part is fixed on the shaft. The high-precision face-machined sliding faces rotate axially in opposition.

The sliding faces are pressed against each other by means of spring force commonly generated by coil springs, thus preventing the opening of the seal at stand-still. The seal faces are statically sealed against the housing and the shaft by secondary seals (O-rings). With the entry of the pumped medium into the minimal sealing gap a lubricating film is generated and the sealing effect is thus obtained.

Flatwire Wave Springs and Retaining Rings are used in various mechanical seals for different kinds of industries to seal fluids, which could pass the area between a static and a rotating element.

Utilizing a Wave Spring instead of a coil spring has a number of benefits:

• Using wave springs will save radial space compared to coil springs with bigger diameters. No additional holes must be drilled into the periphery of the seal housing to provide enough axial space for the coil. This means less machining and less cost to the customer.A wave spring always provides its load in axial direction.
• Very low spring rate with extremely flat load deflection curve could be specified by using a multiple turn wave spring to increase the life time of a mechanical seal.
• Wide radial wall plus shim ends offers wide supporting surface.
• No welding points (compared to welded stamped wave washers) which could break during dynamic stress.
• Stainless steel and other materials could be easily used to provide correct corrosion resistance for our wave springs (e.g. AISI 316 stainless steel for offshore and Hastelloy C276 for chemical applications).

Download our White Paper “The Best Springs You Haven’t Tried Yet” for more information about Rotor Clip wave springs.