From: Dave Roy, Component/System Engineer
Sent: Wednesday, May 10, 2006 10:11 AM
I wanted to give you and update on our experience with the Envelop covers produced for the shipment and storage of submarine trim and drain motors.
As you know these are DC motors that have a tendency to absorb moisture from the air as a consequence of having stood idle for a period of time. We have struggled for some time with motors that were delivered to Naval activities with low insulation resistance even though they tested satisfactory prior to leaving our refurbishment vendors.
In searching for packaging solution we discovered that the Envelop technology used on external surface ship applications may be adaptable to our situation. Using the test cover that was supplied by Shield technologies last year, we evaluated it’s effectiveness on a newly refurbished motor sent to fleet activities.
I’m pleased to report that the motor fitted with the test cover had insulation resistance readings of 2000 megohms when receipt inspected at NNSY (similar to post refurb. values). The unit in question had been sent from a vendor in New Jersey to PHNSY in Hawaii to support an Availability. The unit was not used and ended up being shipped to New London and then NNSY to support a recent DMP.
While not originally intended, the extensive travel and various conditions helped in the overall evaluation. We hope for continued success with the production model covers that are now being introduced. Our east coast refurbishment vendor is now directed to fit the covers on all units refurbished and shipped to fleet activities.
We are in the process of updating packaging requirements for our west coast vendor to add similar requirements. We will continue to monitor the successful use of the covers on trim and drain motors and look to look to apply the technology to other electric motor applications in the future.
We appreciate your continued support with our efforts to improve the refurbished rotatable pool products that are delivered to the fleet.
SUBMEPP Code 1843DR