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HIPPS (high integrity pressure protection systems) applications, equipment mapping exercise and determined that valves and and it can be deployed as a linear process actuator. drivers were among the most important components in any

Other potential applications are suggested for electronic system. He noted: “Leakage rates for new subsea valves are manifolds in double expanding branch valves, and in electronic quite high.” chokes. To prove these new systems, Aker Solutions carried out

Single side low-voltage and dual redundant high-voltage shock and vibration testing of the electronics, with three stages actuators have been developed. Both feature communications used before a qualifcation build. Finite element analysis (FEA) and motor control processors, and motor drivers. was also used to examine and modify the design.

Fitted with dual motor and gear oil systems, the drivers are

Test results made using a high-volume production method – to ensure • component standardisation. They feature thermal management No resonance frequencies on board level with amplifcation through direct convection to sea water. above 5, and below 500Hz.

•

Gearboxes have been tested at up to 1800 Nm with continu- No resonance frequencies with amplifcation above 5, below ous operations, and feature a tailor-made motor unit with life 250Hz.

• time testing successfully completed. The drive unit is designed No notching during a two hour random vibration test.

for predictable fabrication and qualifcation units have been Sub-module qualifcation tests have been conducted for the built on a production line with fully traceable components. A gearbox and motor unit, systems testing has been undertaken, contract manufacturer has been used for electro-mechanical and a system pre-qualifcation test. Formal system qualifcation component production to secure knowledge retention in a testing has also been performed, providing increased confdence cyclic market. in reliability and reduced risk for the unit.

Turning to the economics of the units, a study looking

Future applications for these units are foreseen in HIPPS at the performance of a medium-sized subsea production and Xmas tree actuators: So far, a proof of concept system has system using electric branch valves and chokes indicated been built and tested on a 7in and 3/8in valve. Aker Solutions potential lifetime savings of US$25 million through less already has its I-Con subsea control system, and SubseaWeb hydraulic fuid consumption, less power consumption, and — its subsea architecture concept offering a means of monitor- faster start up times — meaning less lost production time ing and controlling subsea systems, using OPC (open process from a well.

control) connectivity, and transmission control protocol and

Also the electrical system offers the potential for faster failure internet protocol systems.

detection through enhanced monitoring, Larssen explains. With the new hardware, however, the company believes it

During 2012, Larssen said Aker Solutions undertook a subsea has the enablers for a fully electronic subsea system. 082_OE0515_Subsea1+2.indd 85 4/20/15 8:25 PM