Flowserve Corporation in partnership with Shell, has successfully completed factory testing of a twin-screw pump, designed specifically for high-boost subsea multiphase pumping applications.

The new design was tested to a differential pressure of 2500 psi (172 bar), which is a significant milestone in the development of multiphase pumping. The performance was mapped with liquid viscosities varying from 2 cp to 2000 cp. The pump is part of a larger deep-water subsea pumping system initiative, focused on heavy oil applications, sponsored by Shell Upstream Americas.

The pump design has a nominal displacement of 90,000 barrels per day at the rated speed of 1800 rpm for this high-boost requirement. Final design conditions for the system are targeted at 3000 psi (207 bar) boost pressure in multiphase service with a power in excess of 5 MW and a water depth capability of 3000 m.

This development work has been performed as part of an integrated team managed by Shell, together with other specialist suppliers, to provide the necessary core technology for the subsea system. This includes a 3.5 MW high-torque subsea motor from Flowserve, high-power electrical and fiber-optic connectors, and a fiber-optic condition-monitoring system.

Full string testing on the core technology will take place later this year at Flowserve s high-power test facility located in Etten Leur, the Netherlands.