ClydeUnion Pumps, an SPX Brand, and GE Hitachi Nuclear Energy (GEH) brought together five utility companies in February 2013 to witness the successful submergence tests of the CUP-TWL, a turbine driven safety pump that offers significant safety enhancements and is used in both Pressurised Water Reactors (PWR’s) and Boiling Water Reactors (BWR’s). A video of the test can be seen here.
The two eight-hour submergence tests, conducted in Glasgow, UK, successfully demonstrated that it is possible for a hot running pump, under simulated flooding conditions, to continue to run for the full test period with no change in fundamental performance or detrimental damage. GEH invited customers from five utility companies to witness the tests of this safety equipment at SPX’s 76,000 sqm facility, where engineers operated the CUP-TWL in a purpose built tank designed to simulate flood conditions.
The test began with flooding the CUP-TWL with cold water, starting it with design steam conditions, and conducting a series of performance tests and an emergency stop/start while submerged. The test tank was then drained while the unit continued to run and the temperature of the unit was allowed to stabilise with the steam supply at 290°C (554°F) before rapidly flooding the tank with cold water. A second performance test was then conducted with a total of eight hours submerged running with no reduction in performance or integrity.
“The CUP-TWL is already established as an excellent safety related pumping solution due to its ability to function without the need for external services such as lubricating oil and AC/DC power. The results of these tests leave little doubt that this type of cooling pump is capable of enhancing nuclear reactor safety in that, in the rare event where the pump may become flooded, it is specifically designed to continue to work submerged,” said Ranald Patrick, Chief Engineer for SPX’s ClydeUnion Pumps.
“Enhancing reactor safety is a priority for GE Hitachi and the entire industry. We were very pleased with the results of the submergence tests with the ClydeUnion Pumps CUP-TWL,” said Richard Rossi, GEH’s VP for Asset Management. “GEH is currently offering this safety enhancement to several customers, as part of our Alternate Cooling Injection System, to improve submerged startup and operating capability,” Rossi stated.