Tight tolerances for press fit

In comparison to conventional molding or paper tube assemblies, the implementation of the POLYGON TUBE® into the motor assembly enables the manufacturer to reduce production costs. Standard tolerances have been established that allow these composite tubes to be slipped or press-fit into the motor laminations. The armature shaft is then pressed into the assembly, securely locking the laminations and the shaft.

Quality Control

To ensure that each double insulated POLYGON TUBE® surpasses all electrical insulation requirements we have implemented an uncompromising inspection process. Each tube is tested at 5000 volts minimum to guarantee its dielectric integrity. POLYGON TUBE® carries approval by Underwriters' Laboratories, Inc. to grade AFW-G-10. Certification and SPC controlled processing ensures "just in time" deliveries and the eliminates inspection on the customer's end.

The anisotropic properties composite materials are often misunderstood. Therefore, it is helpful to review some of POLYGON TUBE'S® basic material features as they relate to armature insulation.

The Composite Tube Consists Primarily of Two Dielectric Materials:

Reinforcing material: Consisting of continuous fiber bundles of electrical grade "E-Glass" woven together at a specific helix angle with respect to the tube axis.

Epoxy: That has a Tg of approximately 115°C (239°F)

Properties in the axial, hoop, and through the wall in a composite are anisotropic and are controlled with fiber orientation. The composite's physical properties are not less consistent in ultimate strength or elasticity.


Any ratings are typical for design purposes. Your design parameters may affect final ratings. Consult with a Polygon sales engineer for guidance. Final testing and approval is the customer's responsibility for their application. This information is derived from our testing and published data. There is no assurance of these properties, or warranty provided that these products are suitable for any particular purpose or operational situation.

Polygon certifies that their product will be free from material defect. Polygon will not accept any liability for loss, damages, or costs from use or misuse of our products.

Specifications are subject to change, and may be affected by our continual process of improvement. Changes may be made without prior announcement.

POLYGON TUBE® carries approval by Underwriters' Laboratories, Inc. to grade AFW-G-10. A minimum wall thickness of 0.47mm (0.029") is required to qualify for this material designation.