Reduce Inspection Cost for Reactor Internals Using Automated Tooling and Remote Operated Vehicles (ROVs) - MTA-MA-006 Rev. 1

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Administrative Items
Date	12/14/21
Functional Area Where Benefits Will Be Realized	Maintenance
Reference Implementation Guidance	2020 TIP Award Submittal 76 (ID: 13349938) 2018 TIP Award Submittal 13 (ID: 11252868) Materials Reliability Program: Pressurized Water Reactor Internals Inspection and Evaluation Guidelines (MRP-227, Revision 2-A) (EPRI 3002031794) BWRVIP-03, Revision 21: BWR Vessel and Internals Project, Reactor Pressure Vessel and Internals Examination Guidelines (EPRI 3002026476)
Industry SME	EPRI – NDE Contact: NuclearPlantMod@epri.com
Previous Implementation	This improvement has been implemented at several nuclear power plants. Please contact EPRI for implementation examples and contacts.
Implementation Enablers	N/A
Applicability	All PWR and BWR Reactor Types All Geographic Regions
Keywords	ROV examination; reactor internals; in-vessel visual inspection; remote visual inspection; containment inspection; nondestructive examination; MRP; material reliability program; BWRVIP; boiling water reactor vessel and internals program; boiling water reactor; pressurized water reactor; license renewal
Business Case Analysis Cross-Reference	N/A

Description

Reactor internals inspections have become more stringent as a direct result of aging plant components and the development of the Pressurized Water Reactor (PWR) Materials Reliability Program (MRP) and Boiling Water Reactor Vessel and Internals Program (BWRVIP) guidelines for satisfying the NRC requirements for management of aging reactor vessel internals. The guidelines specify higher quality inspections, such as enhanced visual inspection (EVT). Traditional methods of completing these examinations require manual techniques such as pole‑mounted cameras manipulated from the refueling floor. Such techniques can be time‑consuming, hazardous, and make it challenging to get high‑quality images. New automated tooling and ROVs make use of 3D probe and/or high definition (HD) camera technology to perform examinations and small‑area cleaning remotely, increasing inspection quality, traceability, repeatability, and efficiency, as well as reducing dose to personnel. These technologies can include lower‑resolution inspections (with robotic crawlers or submarines) and/or higher‑resolution inspections (with tooling mounted on rail and trolley systems).

In addition to the option for improved inspection data, recent advances in visual inspection technologies (e.g., remote operated tooling) reduce inspection times. This can result in a reduction in the schedule for potential critical‑path activities or an increase in inspection scope to include performing inspections currently performed over two outages during a single outage. This has been accomplished using only automated and remote tooling and can result in significant cost savings.

Benefits

Benefits Estimate

Level 2 – Savings are typically greater than $1 million but less than $5 million per plant per reactor internals inspection relative to using traditional manual techniques. This is largely due to reductions in critical‑path outage time and dose. Performing two outages‑worth of scope in a single outage is estimated to save an additional $1 million by eliminating the need to inspect during the following outage.

Benefits Description

• Reduction in cost to inspect and clean reactor vessel internals by saving critical‑path outage time and reducing dose.
• Increased industrial safety by allowing the inspection to be performed remotely as opposed to in hazardous locations (i.e., high elevations).
• Decreased exposure to radiological hazards due to relocating most personnel outside containment; only one in‑containment person is necessary to manage cables when using automated/remote tooling.
• Increased access to previously inaccessible areas when using the identified technologies.
  • Increased clarity and resolution of data when using automated and/or remote tooling, resulting in improvements in data processing due to advancements in data quality.
  • Increased scheduling flexibility when using ROVs since activities can be performed in parallel.
• Potential additional reduction in cost due to the opportunity to perform current and future inspection scope during a single outage, permitting the skipping of a future inspection without impacting critical path.

Costs and Schedule

Cost

Level 2 – Implementation cost is typically greater than $1 million but less than $5 million per plant per reactor internals inspection. First‑time implementation cost of approximately $2 million, subsequent implementation cost of approximately $1 million. First‑time implementation cost includes fabrication of custom‑sized equipment for the reactor vessel. Both initial and ongoing estimates depend on desired inspection scope.

Schedule

Typically, planning takes between six months and one year. Approximately one to five days to complete the inspection.

Scope Context

Per reactor vessel internals inspection. Initial and ongoing cost estimates are based on vendor‑supported implementation.

Risks

• Using automated tooling and ROVs creates risk for schedule delays due to tooling/ROV technical issues. This can be mitigated through having fully operational spares; reliability of the technology is expected to increase over time.
• Using automated tooling and ROVs creates a risk of foreign material intrusion related to introducing the inspection equipment to the reactor vessel area (e.g., leaving parts behind). This can be mitigated through typical precautions and procedural controls for work in the reactor vessel.
• Vessel condition may limit the capacity of a site to perform current and future inspection scope during a single outage. Vessels with outstanding issues may require expanded scope or re‑inspection in subsequent outages, preventing a plant from fully performing two outages‑worth of scope in a single outage.

SWEEP Score

Category	Level	Description
Cost	2	Using the services of a contractor to inspect reactor internals is expected to cost greater than $1 million but less than $5 million.
Savings	2	Savings are achieved through the reduction of inspection costs (primarily reduction in outage critical path) and are generally expected to be greater than $1 million per implementation but less than $5 million.
Payback	3	Based upon estimated cost and savings information the payback period could be immediate. Additional benefit from condensing two outages worth of scope into a single outage would have a payback period greater than one year and less than five years, since this benefit would not be realized until the next outage.
Technical Readiness	3	This technology has already been implemented at nuclear power plants.
Licensing Readiness	3	The technology is commercially available and has already been used at commercial nuclear sites.
Implementation Proficiency	3	The implementation of the technology has been performed by vendors in the past and does not require the utility to have specific knowledge.