AKM Motor Shaft Seals (Teflon & Viton)
Teflon Shaft Seal
In terms of seal material, PTFE (Teflon) is a good medium to use in terms of low drag. PTFE seals can run dry or wet. One disadvantage is the shedding. The shedding from the PTFE seal is normal; it is a burnishing process that forms the seal to the shaft. A teflon seal can be added in the field but that does not make the straight connector motor IP67. IP67 is only possible through the factory. A tapped plug is added to the potting hole in the side of the motor and the motor is tested per IP67 requirements to ensure compliance.
Viton Shaft Seals
The Viton seal was introduced to the AKM line in the November 18th press release. The seal is available on NEMA or English mounts; they cannot be used with metric mounts due to a counter bore in the pilot face on those mounts. The Viton shaft seal require a press tool to press it in place; these cannot be applied in the field. Viton seals require lubrication (Chevron SRI2 grease or equivalent) or it will “eat” into the steel shaft. The Viton seal will provide superior performance as compared to the Teflon seal. It is also more durable.
Any time you add a seal, you add drag unless the seal is a labyrinth non-contact type arrangement. The torque de-rating is listed in the AKM selection guide and is a result of the additional heating caused by friction.