Inspection of the Inlet and Outlet Nozzle to Shell welds at Beznau NPP Unit 2

Speaker:
Benitez, Jorge; DEKRA Industrial AB; Sweden

Authors:
Benitez, J.; DEKRA Industrial AB; Sweden
Harrison, M.; DEKRA Industrial AB; Sweden
Zaicev, V.; DEKRA Industrial AB; Sweden

ID: ECNDT-0537-2018
Download: PDF
Session: PAUT-Nuclear Industry
Room: H2
Date: 2018-06-13
Time: 09:40 - 10:00

DEKRA Industrial AB has successfully performed a mechanised inspection of the Inlet and Outlet Nozzle to Shell welds at Beznau NPP unit 2 in the Outage in 2017.
The inspection was performed from the inside of the Reactor Pressure Vessel (RPV) using DEKRA developed manipulator Grotte able to scan from both RPV wall as well as from the Nozzle Bore. The manipulator Grotte was qualified by according the Swiss regulation by QSt (Swiss Qualification Center).
DEKRA Industrial AB developed the NDE technique and qualified procedure according to the Swiss rules by QSt.
The NDE technique is based in a combination of the following techniques:
• Eddy Current
• UT conventional (Pulse-echo)
• TOFD
These procedures are valid for detection, characterisation, positioning, length and height sizing of:
• ID Zone: Circumferential and axial defects using both Ultrasonic (UT) and Eddy Current (ET) techniques for inspection of ID zone (wet surface to 26mm from the wet surface) at the Inlet and Outlet Nozzle to Shell welds.
• Inlet Nozzle Volume Zone: Circumferential and Axial defects using Ultrasonic (UT) techniques for inspection of volume zone
• Outlet Nozzle Volume Zone: Circumferential and Axial defects using Ultrasonic (UT) techniques for inspection of volume zone
The inspection was performed in parallel with two manipulators and was completed in less the 6 days.