Sea Technology

JUL 2018

The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community

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Page 13 of 44 July 2018 | ST 13 chamber. The penetrators were then cleaned with a mix- ture of soap and water. The entire ETP-6510-101 testing procedure was overseen by an on-site ABS inspector, who verified the integrity and accuracy of all tests per- formed. All relevant documents, calibration certificates, drawings, procedures and data capture points pertaining to testing were reviewed and manually approved by the ABS inspector underwriting the results of the testing. This on-site inspection was conducted once for the insert he- lium leak testing and once during hydrostatic pressure testing and electrical testing after termination and poly- urethane overmolding. When the completed assemblies were shipped to DeepFlight's team in California, they were inspected and tested by applying vacuum pressure to all completed as- semblies to verify seal integrity before installation on the sub. The testing of the complete system continued during sea trials before heading to the team's submarine base in the Maldives. The penetrator assemblies continue to perform well since the successful launch of the Deep- Flight Super Falcon 3S line, and the sub is in frequent use at its first resort in the Maldives, introducing travelers to unique new views and ways to experience flight in the ocean. Acknowledgments The author would like to thank the team at DeepFlight for providing valuable data and images for the develop- ment of this article. ST Amy Brown is the chief marketing officer for BIRNS Inc. and is responsible for developing and managing a comprehensive set of strategic marketing and communications programs. facility (certified for fabrication of U.S. Navy submarine outboard cables). The overmolding process began with wire terminations being encapsulated with epoxy adhe- sive, and polyurethane subsequently injected into mold cavities to harden and cool. This sealed the penetrator/ cable interface, provided strain relief, precluded dis- continuous bending and added elastomeric mechanical strength to the junction. Many of the penetrator assem- blies for the project also had complex junction molds, splitting into two segments (Y molds) or up to four seg- ments. These challenging overmolds require particular care during the process; the technician must ensure that there is sufficient slack for the wires in the mold cavity, to avoid sealing them in with too much tension, while keeping these high-density wires centered in the mold and not allowing any wires to touch the mold cavity. If that were to happen, it could create a direct leak path into the assembly and could allow water ingress, which might cause it to short. Each penetrator assembly was then tested for con- tinuity and IR once again, prior to formal ABS witness acceptance testing. Next, the complete assembly was subjected to a dielectric withstanding voltage (Hi-Pot) Test—where each conductor is tested at 1,480 V DC for 60 sec., before automatically moving to the subsequent channel, with a reading below 29 µA required to pass. Then, a six-cycle saltwater hydrostatic pressure test was performed, in which the outboard side of the penetrator is held to pressure of 1,000 psi. During the sixth cycle, while under pressure, the entire penetrator was given another extensive IR test at 500 V DC for the 25 con- ductors, testing between each conductor and all other conductors, and between each conductor and the test The DeepFlight Super Falcon 3S and three occupants underway from the Four Seasons Resort Maldives at Landaa Giraavaru. (Inset) The composite-hulled DeepFlight Super Falcon 3S was specifically designed for tourism and ease of operations and offers the experi- ence of flight in the ocean.

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