Nuclear Services

Nuclear Services

Nuclear Services 

SOCOTEC’s engineering and technical staff have provided support and engineering services to both US and international nuclear plants for nearly sixty years. Our experts have been called upon to investigate component failures, provide engineering support for component improvement, and to demonstrate system operability. Depending on specific needs, clients typically collaborate with us through one of our service offerings or directly based on the areas of specialization and expertise of our staff. 

Component Operation Simulation 

SOCOTEC can develop component operation simulation using a combination of modeling, kinematics and analysis to simulate performance under operating scenarios. SOCOTEC's experience has encompassed various air-operated valve and check valve behavior, simulation sequencing of spent nuclear fuel loading into casks, and construction load sequencing. 

We have capabilities to test component performance through data acquisition and digital capture. 

Operability Assessments 

The life expectancy of components is continually challenged with the aging of the nuclear fleet in the US. This often results in degraded conditions that require assessments to support continued plant operation. SOCOTEC’s engineers have evaluated many such components, often with tight schedules necessary to support determinations. We can quickly mobilize experts to work independently or with plant teams to develop the technical basis in support of plant operability determinations. 

Nuclear Program Support Services 

SOCOTEC has been actively involved in many of the most significant programs in the nuclear industry in the last 20 years. These have included FAC programs, valve programs, service water system fluid transients, buried piping and gas intrusion analysis services. 

Talk to our experts

Paul BRUCK

Principal

Principal

paul.bruck@socotec.us +1 978 378 1180

Sontra YIM

Principal

Principal

sontra.yim@socotec.us +1 978 378 1182
flow accelerated corrosion - wall thinning inspection for nuclear plants

Nuclear Services

Flow Accelerated Corrosion (FAC)

FAC can lead to wall thinning in pipes, valves heater shells, and tanks in BWR, PWR, and CANDU nuclear plants and within fossil power plant systems. FAC is the dissolution of the normally protective oxide layer on the inside surface of carbon and low alloy steel piping. The iron oxides that naturally form on the exposed surface of the pipe are removed by mass transfer to the de-oxygenated water flowing over the pipe's inside surface. 

Resulting failures of pressure components can lead to catastrophic events, with significant downtime for repairs. SOCOTEC’s personnel have been involved in FAC assessments of piping systems since the early identification of this problem in US nuclear plants. Our experience extends to all nuclear power plant types, and the review of a significant number of fossil stations. 

We understand how plants operate and work closely with plant personnel, soliciting input and valuable insights from system engineers, operations, maintenance, and NDE personnel.  

FAC can lead to wall thinning in pipes, valves heater shells, and tanks in BWR, PWR, and CANDU nuclear plants and within fossil power plant systems. FAC is the dissolution of the normally protective oxide layer on the inside surface of carbon and low alloy steel piping. The iron oxides that naturally form on the exposed surface of the pipe are removed by mass transfer to the de-oxygenated water flowing over the pipe's inside surface. 

Resulting failures of pressure components can lead to catastrophic events, with significant downtime for repairs. SOCOTEC’s personnel have been involved in FAC assessments of piping systems since the early identification of this problem in US nuclear plants. Our experience extends to all nuclear power plant types, and the review of a significant number of fossil stations. 

We understand how plants operate and work closely with plant personnel, soliciting input and valuable insights from system engineers, operations, maintenance, and NDE personnel.  

Nuclear plant valve failure analysis and specification inspection

Nuclear Services

Valve Programs

Our valve analysis experience extends over many years, with active involvement since the beginning of the GL89-10 motor-operated valve program in US nuclear plants. Our engineers have performed assessments using our structural engineering capabilities to develop weak link assessments, our mechanical engineering abilities to perform set-up and capability evaluations, and our fluid engineers predict flow, drag, blow-down, and check valve performance. SOCOTEC's capabilities and service encompass: 

 

  • Valve failure analysis 

  • Valve and actuator mechanical analysis 

  • Qualification of valve designs to meet structural and performance specifications 

  • Analysis to predict valve performance for motor-operated, air-operated, and hydraulically operated gate, butterfly, globe and check valves 

  • Valve/actuator design modifications 

  • Valve analysis per ASME code requirements 

Our valve analysis experience extends over many years, with active involvement since the beginning of the GL89-10 motor-operated valve program in US nuclear plants. Our engineers have performed assessments using our structural engineering capabilities to develop weak link assessments, our mechanical engineering abilities to perform set-up and capability evaluations, and our fluid engineers predict flow, drag, blow-down, and check valve performance. SOCOTEC's capabilities and service encompass: 

 

  • Valve failure analysis 

  • Valve and actuator mechanical analysis 

  • Qualification of valve designs to meet structural and performance specifications 

  • Analysis to predict valve performance for motor-operated, air-operated, and hydraulically operated gate, butterfly, globe and check valves 

  • Valve/actuator design modifications 

  • Valve analysis per ASME code requirements 

Nucelar Services degradation of buried pipes - advanced analysis and fitness for service

Nuclear Services

Buried Piping Programs

Degradation of buried piping is a major issue facing nuclear power plant owners, and many plants will require repair or replacement of existing carbon steel piping components. Although degradation mechanisms are often slow, they are progressive. As plants reach 30 and 40 years of operation, increased instances of inadvertent radiological release from these underground systems are expected, based on the industry experience to date. This has been an issue for license renewal, and plants have generally been required to commit to opportunistic inspections of these underground systems. 

Many nuclear plant systems contain one or more lines that are buried. These systems may include safety and non-safety service water, circulating water, fire protection, diesel fuel oil, spent-fuel pool cooling water, miscellaneous radioactive lines, off-gas, and yard drains. Many buried lines are coated or tape-wrapped with materials such as concrete, coal tar, asphalt-based materials, or epoxy. Although many of these lines were cathodically protected when plants were constructed, in many cases the cathodic protection system may not have been maintained or used consistently. The result is accelerated external degradation at locations where the coating has failed. Additionally, certain systems can be subject to internal corrosion as a result of microbiologically influenced corrosion (MIC), and other degradation mechanisms. 

Degradation of buried piping is a major issue facing nuclear power plant owners, and many plants will require repair or replacement of existing carbon steel piping components. Although degradation mechanisms are often slow, they are progressive. As plants reach 30 and 40 years of operation, increased instances of inadvertent radiological release from these underground systems are expected, based on the industry experience to date. This has been an issue for license renewal, and plants have generally been required to commit to opportunistic inspections of these underground systems. 

Many nuclear plant systems contain one or more lines that are buried. These systems may include safety and non-safety service water, circulating water, fire protection, diesel fuel oil, spent-fuel pool cooling water, miscellaneous radioactive lines, off-gas, and yard drains. Many buried lines are coated or tape-wrapped with materials such as concrete, coal tar, asphalt-based materials, or epoxy. Although many of these lines were cathodically protected when plants were constructed, in many cases the cathodic protection system may not have been maintained or used consistently. The result is accelerated external degradation at locations where the coating has failed. Additionally, certain systems can be subject to internal corrosion as a result of microbiologically influenced corrosion (MIC), and other degradation mechanisms. 

Nuclear values of likelihood of occurrence and consequence of failure

Nuclear Services

SOCOTEC Value

SOCOTEC can offer our clients the expertise of our staff with extensive experience in corrosion control, program development, and fitness-for-service assessments. Our experience encompasses program development services, including risk ranking, NDE planning, direct examination, and data evaluation, based on our comprehensive Fitness-for-Service expertise. 

Our experience includes: 

  • Fleet support services for a leading US operator 

  • Model and database development 

  • Risk ranking of fleet SSCs (including radiological piping, tanks and sumps) 

  • Drawing development for ease of location of plant SSCs and monitoring wells 

SOCOTEC can offer our clients the expertise of our staff with extensive experience in corrosion control, program development, and fitness-for-service assessments. Our experience encompasses program development services, including risk ranking, NDE planning, direct examination, and data evaluation, based on our comprehensive Fitness-for-Service expertise. 

Our experience includes: 

  • Fleet support services for a leading US operator 

  • Model and database development 

  • Risk ranking of fleet SSCs (including radiological piping, tanks and sumps) 

  • Drawing development for ease of location of plant SSCs and monitoring wells 

Nuclear System and Component Aging

SOCOTEC has performed extensive system and component aging and life cycle management evaluations. These have ranged from procedures for inspection or system walk-downs to prediction of failure probability to the end of plant operation.

SOCOTEC’s personnel have worked extensively both on programs for Life Cycle Management and individual component life cycle assessments. Evaluations of specific equipment have included buried piping and infrastructure, rotating equipment, cables, large NSSS equipment, and others. Programmatically, SOCOTEC personnel have developed methods to systematically assess degraded conditions. This has included training of personnel and implementation of programs.

This topic is particularly pertinent as operating plants extend their licenses and look at maintaining high operating reliability and containing costs. This places a premium on the quality of decision-making that assures all expenditures are focused on maintaining safety and reliability. Since 2014, SOCOTEC engineers have been working with EPRI to develop innovative tools to predict the remaining life of critical plant assets—components, systems and structures—as well as tools to develop asset strategies and perform financial evaluations for informed decision making. In conjunction with Argonne National Laboratory, we have developed a system for real-time monitoring of critical plant fluid and electrical systems to allow operators to predict and assess issues before they occur.

SOCOTEC has provided services to owners to assist them in assessing the condition of their concrete structures. Services include evaluation of particular causes of concrete aging such as alkali-silica reaction, freeze-thaw, calcium leaching, rebar deterioration. Since 2012, SOCOTEC engineers have researched long term radiation effects on nuclear plant concrete, developing a methodology for predicting and evaluating concrete conditions for plants extending their operating lives beyond 60 years. In addition, our experts have been working on new technologies for concrete structural monitoring, including digital image correlation, image change detection, and fiberoptic and wireless strain network measurements.

SOCOTEC’s services include:
-Long-term monitoring, and crack assessment
-Core sample analysis, compression testing, chemical analysis and petrographic examination
-Pre- and Post-tensioned concrete monitoring and aging assessments, including tendon cable assessment
-Cable assessment
-Rebar corrosion prediction
-Permeability assessments

SOCOTEC engineers have performed a wide variety of evaluations for nuclear plant systems, structures and components. Examples include:

-Structural assessment of plant buildings: containments, vacuum buildings, refuel cavities, off-gas stacks, floors and steel structures
-Spent fuel pool degradation assessment for boric acid corrosion
-Heavy load analysis of concrete floors and pads
-High energy line breaks effects on buildings
-Extreme loads (flooding, seismic, design basis threats) analysis
-Investigations into mechanical system/component performance, failure and aging.
-Thermal hydraulic analysis of high energy piping systems and components
-Piping and pressure vessel stress analysis and code qualification

A number of plants have experienced leakage from fuel pools and transfer canals, leading to tritium contamination. Such leaks are often very small and usually below the measurement threshold available to in-plant installed systems. SOCOTEC personnel have designed test configurations and conducted long-term tests to quantify the leakage from pools down to small quantifiable amounts. SOCOTEC personnel have also performed remote inspection and direct inspection of transfer canal liners to identify leakage areas and develop repair strategies. Long-term leakage from spent fuel pools often raise questions relative to effects on concrete and reinforcing bars as a result of boric acid corrosion. SOCOTEC has performed a number of assessments to predict damage, including extraction of concrete samples deep into the spent fuel pool wall, and assessment of concrete performance from decommissioned nuclear plant spent fuel pool facilities.

As nuclear plant owners are faced with complex challenges ranging to in-vessel component qualification, primary coolant loop assessments for power uprate and life extension or degradation from in-service corrosion mechanisms, the solution to such problems can be challenging and complex.

To assist plant owners, SOCOTEC experts work alongside the owner to assist in the technical assessment of NSSS evaluations or act in an independent advisory role with third-party review services.

Our projects have ranged from steam dryers in BWRs, vessel nozzle issues, steam generator tube degradation, RCP mechanical seal failure, and others.

Nuclear System and Component Aging services

Want to know more about our Nuclear services? Contact us

Contact Us
paul.bruck@socotec.us

Talk to our experts

Paul BRUCK

Principal

Principal

paul.bruck@socotec.us +1 978 378 1180

Sontra YIM

Principal

Principal

sontra.yim@socotec.us +1 978 378 1182