VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION on the DEWETRON DEWE-5000 Bob Thomas Seabrook Station Grant Smith Dewetron, Inc PRDUG MEETING,

VISUAL SET POINT VERIFICATION METHODS

USED AT SEABROOK STATIONon the

DEWETRON DEWE-5000

Bob ThomasSeabrook Station

Grant SmithDewetron, Inc

PRDUG MEETING, ORLANDO, FLA.

JANUARY 17-19, 2005

Seabrook Relief Valve Team 2

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

• ENHANCED SAFETY - The valve discharges are hard piped, protecting the operators from escaping flow. The operator monitors valve performance from a data collection system removed from the valve.

• CONSISTENCY - The use of a video based data package eliminates the “peek and hide” method of set-point verification which has in the past caused missed set-points. With this method, the operator can look directly at the first steady flow without risk of injury due to escaping steam, water or air.

• REDUCED FAILURE RATES -The video based technique is performed per procedure. Since its implementation, the number of test failures have continually decreased.

Seabrook Station uses direct observation of flow (via video) at the valve seating area to determine relief valve set points. Seabrook has used this method since 2000 with the following benefits:

Seabrook Relief Valve Team 3

WHY VIDEO?In 2001 Seabrook went through a code revision. ASME O&M Code 1995 Edition, 1996 Addenda, which required set point testing at elevated temperatures. Seabrook and Dunn’s Testers developed test stands to meet the new requirements. The new test equipment exposed personnel to increased hazards which resulted from flashing fluids and high volumes. This necessitated the use of hard piped exhausts.

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

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Seabrook Relief Valve Team 4

Closed exhaust piping made liquid set-point verification difficult. Seabrook fabricated exhaust piping to facilitate video observation of valve internal conditions. The piping configuration allows the camera a direct view down the centerline of the exhaust pipe.

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

Camera

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Seabrook Relief Valve Team 5

The standard Dunn’s Data Package was modified to accept the real time video feed, from the camera, into the main test screen. The operator could mark the chart, using the space bar, when he or she observed the first steady stream.

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

Seabrook Relief Valve Team 6

By using this method, we ensured operator safety and repeatable set point determinations. As a result, the number of set point failures and scope expansions steadily decreased each refueling. In ORO9, only one failure occurred.

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

Seabrook Relief Valve Team 7

The original data package allowed us to get started safely in our hot test program. However, after working with the package, it became clear that enhancements were needed. System deficiencies were as follows:

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

• The video data and other test data was not displayed simultaneously, aside from the initial test. This occurred because the video data was captured only on tape within the camera itself.

• The software customized for our use, subsequently required costly programmers for even minor changes.

Seabrook Relief Valve Team 8

Additionally…• Intermittent software glitches were experienced:

the program occasionally froze and features disappeared and reappeared.

• The base program used had become outdated in the industry.

• The package did not record or display; valve, process or ambient temperatures.

• Data displayed was not continuously streaming. As a result, an additional set of pressure indicators was required for valve heat-ups and leakage tests.

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

Seabrook Relief Valve Team 9

2004 DATA PACKAGE UPGRADE

TO >

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

FROM >

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Seabrook Relief Valve Team 10

• The test can be replayed from one file. Pressure, temperature, video and LVTD data are time stamped during recording.

• The tests files can be burned to CD and archived. This is useful if valve performance is later questioned or when performing tests for other plants in the fleet.

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

Seabrook’s test stand data packages were upgraded in 2004 . The Dewetron DEWE5000 was selected as our new test platform. Dewetron, which specializes in the hi-tech data gathering systems, had an off the shelf unit that solved our problems. The Dewetron unit features:

Seabrook Relief Valve Team 11

Additionally…• The unit was reasonably priced compared to other

data packages.

• Dewetron specializes in data acquisition…not valve testing equipment.

• The standard Dewetron software requires no special programming.

• The Dewetron software can be installed on an unlimited number of work stations. This gives maintenance technicians and system engineers the ability to review completed tests at a later date. Test files can also copied to the site LAN.

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

Seabrook Relief Valve Team 12

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000

The Dewetron DEWE 5000 is completely self contained. The CPU, monitor and all interface cards are included in one unit. Data is continuously streaming, eliminating the need for redundant pressure indicators.

Seabrook Relief Valve Team 13

• The test screen includes: pressure, elapsed time, displacement, video and four channels of temperature data.

VISUAL SET POINT VERIFICATION METHODS USED AT SEABROOK STATION

DEWETRON-DEWE 5000