Engineering Resources

Engineering Data
Engineering Reference Handbook
How to Specify Custom Parts
Engineering Reference Handbook

Clamps & Brackets
Expansion Plugs
Metallic Flat Washers
Miscellaneous Electrical Hardware
Miscellaneous Washers
Non-Metallic Washers
O-Rings
Retaining Rings
Sheet Metal Nuts
Shoulder Washers
Solder Lugs
Solid State Insulators
Spring Clips
Spring Washers
Spacers
Tab, Key & Notch Washers
Tags


Non-Metallic Flat Washers

• A flat disc with centrally located hole.
• Electrical and thermal insulation or isolation.
• Sealing — because they can conform to the surface configuration.
• Cushioning — because of elastic or plastic properties.
• Protects surface finishes.



Acetal 5614

• Good electrical insulator (400-465 v/mil)
• Low water absorption rate
• Good cold flow resistance
• High strength for a non-metallic
• Good bearing qualities
• High toughness



Fibre 5602

• Low cost
• Fair electrical insulator (150-250 v/mil)
• Fair mechanical properties
• Good thermal conductivity for a non-metallic
• (.25 btu/hr/sq ft/°F/ft)
• Good cold flow resistance
• Not recommended for humid environments



Fibreglass Epoxy 5621

• Good electrical insulator (400 v/mil)
• High mechanical strength at room temperature
• Low water absorption rate
• Good dimensional stability
• Not recommended for extremely high compression applications


Melamine 5621

• Good thermal conductivity for a non-metallic
• (.29 btu/hr/sq ft/°F/ft)
• Best mechanical properties of fibreglass
• Good electrical insulator (350 v/mil) particularly in humid environments
• Good dimensional stability
• Non recommended for extremely high compression applications

Kapton 5611

• Excellent electrical insulator (7000 v/mil)
• Good for high temperature applications
• High dimensional stability

Mica 5624

• Excellent electrical insulator (3000-6000 v/mil)
• Excellent for high temperature applications
• Relatively expensive to fabricate
• Material tends to flake and chip

Mylar 5622

• Extremely good electrical insulator (4000 v/mil)
• Less expensive alternate to Kapton for lower temperature applications
• Good dimensional stability

Neoprene 5613

• Cushioning properties
• Excellent abrasion resistance
• Fair mechanical properties
• Good oil & gasoline resistance
• Excellent flame resistance
• Excellent sealing qualities
• Resilient — tear resistant

Nylatron (Molybdenum disulfide impregnated nylon) 5615

• Excellent anti-frictional properties
• Heat resistant to 400°F
• Stronger than nylon and better dimensional stability
• Not recommended for an electrical insulator

Nylon (Polyamide) 5610

• Good electrical insulator (385 v/mil)
• High strength
• Good anti-fractional properties
• Heat resistant to 300°F

Phenolics CE 5620

• Good electrical insulator (225 v/mil)
• Good cold flow resistance
• Fair water absorption rate
• Moderate shear strength

LE 5620

• Good electrical insulator (225 v/mil)
• Mechanical properties not as good as “CE” but better than “XXXP”
• Easiest to fabricate

XXXP 5620

• Lowest water absorption rate
• Good electrical insulator (325 v/mil)
• More difficult to fabricate

Polyethylene 5617

• Low cost — very common plastic
• Good electrical insulator 460 v/mil)
• Very low water absorption rate
• Good sealing properties

PTFE 5612

• Excellent chemical and corrosion resistance
• Very low water absorption rate
• High heat resistance
• Excellent anti-fractional properties
• Excellent impact strength at low temperature
• Good electrical insulator (480 v/mil)
• Great for frying eggs!