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Circular washer which are pre-formed with smooth flowing undulations, thus creating a product with spring properties when compressed.

WAVED WASHERS

Emmotts is internationally renowned for its range of waved washers used to pre-load bearings in electric motors. Recent development have enabled the company to address diverse applications in situations where relatively high loads are required from limited deflections, for example seals and valves. Split or slotted waved washers can be produced also and materials range from spring and stainless steel to copper and nickel alloys.                                                     Investment in a custom designed CAD package for these products has ensured Emmotts market lead.

DESIGN CONSIDERATIONS

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= Load

= Young's Modulus

= Rim Width of Washer

= Material Thickness

= Number of Waves

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= Mean Diameter of washer

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= Inside Diameter

= Outside Diameter

Load Calculation

W = Ebt3N4Do

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2.4D3Di

CASE STUDY ONE

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CONSIDERATIONS

Choice of base material, eg - stainless steels, beryllium copper, phosphor bronze, spring steel and plated, should take into account the environment within which the spring will be required to operate.

Operational parameters, such as likely movement or cycle of washer, which will dictate the required edge condition of the material , eg - de-burring, and any pre-stressing requirement.

Load tolerances in operational state.

Expansion of diameters when the washer is compressed should be considered at the design stage.

APPLICATION - A range of waved washers for pre-loading bearings in electric motors.

PROBLEM - Due to the increased operational speeds, excessive rattle and vibration was being experienced in a range of electric motors. This was resulting in excessive wear on the bearings, causing failure and fatigue problems.

SOLUTION - After careful consultation, a special series of waved washers was produced to provide highly defined pre-loads. This was achieved by increasing the number of waves and material thickness from those of George Emmotts standard range. The resultant elimination of end play in the motor and bearing assembly increased its active life.

Follow these links for details of our stock waved washers in metric or imperial sizes:

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George Emmott (Pawsons) Ltd, Wadsworth Mill, Oxenhope, Keighley, West Yorkshire, BD22 9NE. Tel : 01535 643733; Fax: 01535 642108

Contact us via e-mail or by filling out the reply form.