TOP401 technological obsolescence programme

Programme Description

Many plants are facing increasing demands related to technological obsolescence (further also referred as “obsolescence”) of components due to many suppliersno longer supporting warranty and equipment services or have terminated production of components and spare parts. This puts the operating organization ina vulnerable position, leaving few acceptable options, including re-engineering or reverse engineering, substituting newer models that often do not fit the original configuration envelope, upgrading technology or finding parts from other operating organizations.Nuclear power plants experience and react to unplanned, emergent issues related to obsolete equipment. These emergent issues are generally discovered when the equipment fails or during the procurement cycle. The procurement cycle typically occurs 12 to 18 weeks before work starts.

The purpose of this programme is to provide operating organizations with a general format for development and implementation of a proactive obsolescence programme to manage the impact of obsolescence on the availability and reliability ofsystems, structures and components (SSCs). Each operating organization tailors its programme to its specific needs using available software tools on the market and implementing processes for communicating with other operating organizations.

An obsolescence programme can be developed as a stand-alone programme or incorporated into existing plant processes [1](e.g. maintenance programme, equipment reliability programme)andused in a way that proactively identifies obsolete equipment, prioritizes obsolescence issues, andenables proactive development of replacement solutions.

A formal obsolescence management procedure is put in place with clearly defined roles and responsibilities relating to obsolescence programme performance and reporting requirements of obsolescence issues.

New and existing plants are increasingly relying on digital equipment. Digital Instrumentation & Control (I&C) equipment has a finite technology life time. Developing an overall strategic plan can help mitigate some of the risks associated with digital equipment obsolescence and is considered a part of the overall life cycle management plan. Beyond the scope of this obsolescence programme, special considerations are needed when planning replacements of both analogueand digital I&C equipment with digital I&C replacements. EPRI document [2] provides specific methods for managing digital-system obsolescence.

IAEA Safety Guide NS-G-2.12 [3] contains general recommendations on safety aspects of managing obsolescence and requires proactively managing SSCs important to safety.

EPRI documents [4], [5], [6], INPO document [7], and industry experienceswith implementingproactive obsolescence programmes were used as a reference for the development of this programme.

Evaluation and Technical Basis

  1. Scope of the technological obsolescence programme:

The scope of this programme includes SSCs important to safety and spare parts required to maintain those SSCs and may be applied to all SSCs important for plant reliability and availability.

Technological obsolescence is defined as “Lack of spare parts and technical support; lack of suppliers and/or industrial capabilities” in NS-G-2.12 [3].

The scope of this programme is limited to the subject of technological obsolescence in nuclear power plants. The focus is on “part obsolescence,” and “component obsolescence” which refers to parts, materials, and components likely to be replaced one or more times over the lifetime of a plant. This programme does not address physical ageing, “knowledge” and “standards and regulations” obsolescence.

Technological obsolescence considerations:

  • If an item is no longer supported by the manufacturer to maintain an item or model, or is otherwise difficult to procure and qualify, the original item needs to be replaced and the item is considered obsolete.
  • If an item is obsolete but it is in stock, it remains obsolete. This means that technological obsolescence does not depend on stock, but on the ability to acquire the item in market.
  • If the manufacturer changes only the model or commercial denomination of an item, the original item is considered obsolete.
  • If a manufacturer no longer provides the model with adequate qualification documentation, the item is considered obsolete.
  • If a manufacturer no longer provides the model with the same specifications (dimensions, material, footprints, etc.), the item is considered obsolete.
  1. Proactive technological obsolescence actions to minimize and control obsolescence:

In order to develop an effective proactive obsolescence programme, anoperating organizationhas responsibility for supporting the obsolescence programme.The proactive obsolescence programme includes three basic elements: identification, prioritization, and solution development.

The following describes the organization and the methodology fordeveloping a proactive programme:

  1. ORGANIZATION

The following organizations all have a shared responsibility for obsolescence: procurement engineering, design engineering, supply chain, maintenance, operations, and system engineering. This equates to anoperating organization wide challenge. Specific roles and responsibilities for each group to develop a proactive programmeare defined. Examples of this definition can be found in [5].

Obsolescence owner performs typical management functions, including governance of the obsolescence programs and processes, and coordinates activities among different plant organizations. With the information captured through various performance indicators/metrics, the obsolescence owner periodically assesses programme and process effectiveness, improvement opportunities and resource required. The obsolescence owner also ensures alignment with the plant’s other equipment reliability programmes to prioritize obsolete components (e.g. scope and screening based on AP-913 [8] classification, critical components).

Obsolescence committee is comprised of experts among key departments such as operations, maintenance, engineering, and procurement that are involved in identification, prioritization, and resolution of obsolete items. Committee performs review of known unsolved obsolescence issues, plant risk, and recommended actions. It is usually a subcommittee of the plant senior management committee.

Obsolescence specialists like engineering, materials, or procurement personnel who perform daily tasks associated with managing obsolescence are involved in identification, prioritization, and resolution of obsolete items.

  1. METHODOLOGY

The first step in establishing a proactive obsolescence programme is to develop a baseline listing of equipment and associated items in the plant. Typically, this entails compiling a list of plant equipment and replacement parts typically contained in existing plant databases and information systems. Inaccurate data can result in incomplete or inaccurate obsolescence status since the minimum information required to determine if an item is obsolete consists of manufacturer and model information or part number.

In cases wheredata is missing or cannot be interpreted, the plant is unable to determine an obsolescence status for these components. These components may impact availability of items important to safety, have the potential to extend or cause unplanned outages orcause preventive maintenance task deferrals. By proactively addressing the issue of missing or incomplete data, these risks can be mitigated.

In order to identify this missing information, a data clean-up (identification) effort canbe performed by:

  • Document review and data capture through the site’s existing data sources;
  • Physical walk-downs of the equipment; and/or
  • Use of available industry software tools.

After themanufacturer and model numbers are identified for plant equipment, an effort is made to determine if the original manufacturer still manufactures the product, or supports the product by providing refurbishment or spare parts. The supply chain organization is typically responsible for this task as it has access to suppliers`contact information. The basic methodology involves the following three processes:

IDENTIFY the scope of installed equipment and replacement items that are no longer manufactured or are otherwise difficult to procure and qualify is the first step. Sources of this information include:

  • Demands due to reduced spare inventory;
  • Demands due to plant maintenance;
  • Plant personnel who identify issues during daily plant activities;
  • Inputs from suppliers;
  • Information from other plants or from external sources;
  • Proactive vulnerability reviews (targeted reviews of plant equipment to identify obsolescence problems in advance of discovery through equipment failure or through the daily procurement process, e.g. [7]);
  • System, programme, and/or component health reports and assessments;
  • Industry obsolescence databases; and
  • Supplier contact reviews or other relevant factors.

PRIORITIZE these items in a manner that determines the highest obsolescence vulnerabilities to the plant. Three focus areas are taken into consideration:

  1. The importance of the component to the plant;
  2. The plant demand for the part; and
  3. Spare part availability in the plant warehouse.

This prioritization scheme is performed based on component classifications, work order information, stock history, failure history, or any additional criteria determined by operating organization. The relative importance of each factor is determined by the operating organization, and a relative weight or importance is assigned for each factor [6]. Based on operating experience, the prioritization scheme changes over time as the programme matures to incorporate lessons learned. The prioritization scheme is based upon the above.

It is possible to have enough spare parts in stock of the obsolete item in good conditions to guarantee safe and reliable operation for a reasonably long period of time. Each site can have plantspecific priorities. Generally, the following factors are considered when prioritizing proactive obsolescence challenges:

  • Number of identical equipment in operation in the plant;
  • Current inventory levels;
  • Consumable history of spare parts;
  • Failure rate of equipment;
  • Historical lead time;
  • Maximum and minimum stock revision;
  • Upcoming demand for maintenance;
  • Ageing of equipment in stock;
  • Classification of the equipment based on criticality (critical, non-critical, run to maintenance);
  • Safety impact and reliable operation of the plant if failure/unavailability of that item occurs; and
  • Ability to maintain obsolete component using available spare parts.

IMPLEMENT SOLUTIONS for obsolete items in an effective and timely manner. The types of solutions can vary from minor design changes and equivalency evaluations to reverse engineering and major design modifications. Based on available response time, the least expensive solutions can be researched, and a parallel path approach can be taken until the issue is resolved. Usually operating organization prefers a graded approach to identify the least costly and resource intensive solution to solve the problem. Possible solutions are the following:

  • Procurement engineering: equivalent replacement, surplus markets, and special manufacturing runs;
  • Plant engineering: rebuild/repair, and reverse engineering; and
  • Design engineering: design change.
  1. Detection of technological obsolescence indicators:

In addition to the identification of plant equipment and items that are already obsolete, early warning indicators can identify equipment and items that are likely to become obsolete in the near future. The following are examples of early warning indicators:

  • Changes in the suppliers’ owner structure, e.g. brands that are bought or sold to another company;
  • Outsourcing of manufacturing;
  • Long lead times and high price;
  • Manufacturing quality problems;
  • Information and knowledge that is shared in national and international networks is used and taken inconsideration to detect obsolescence;
  • Information from regular contacts and meetings with manufacturers and suppliers;and
  • Self-assessment programmes, manufacturer reports, plant purchasing sector reports, international databases of obsolescence report, or SSC responsible sector reports.
  1. Monitoring and trending of technological obsolescence:

Effective obsolescence management considers performing an obsolescence programme or process assessment and developing health report and metrics. Programme metrics are directed to senior management to identify risk, progress, financial resources, and to gain alignment of priorities for an obsolescence programme. Descriptions of metrics can be found in [7].An obsolescence programme assessment is typically performed to identify gaps relative to plant obsolescence programme, international guidelines and other operating organization programs and processes. The assessment identifies recommended actions for strengthening the effectiveness of the obsolescence programs and processes.

It is important to monitor the effectiveness of the obsolescence programme and continuously seek to improve performance and efficiency.Two types of activities are recommended:

  • Periodical obsolescence programme assessment; and
  • Development and monitoring of meaningful performance indicatorson a periodic basis (e.g. quarterly).

Consider the following obsolescence questions and attributes when developing the assessment scope:

  • Is there an obsolescence programme or process description or guideline describing implementation?
  • Does it include roles and responsibilities?
  • Is there a designated obsolescence owner?
  • Is there an obsolescence committee involving key departments such as operations, maintenance, engineering, procurement?
  • Are obsolescence vulnerability reviews performed to identify critical obsolescence issues?
  • Is there a tools being utilized to support identification, prioritization, and research of solution for obsolete components?
  • Are there information exchanges or collaboration initiatives with other operating organization?
  • Do system and/or component health reports contain a section on obsolescence vulnerabilities?
  • Are metrics used to monitor the programme and process health?
  • Has the programme proactively resolved any obsolescence challenges?
  • What lessons have been learned (what could have been done better) from the obsolescence programme development and implementation?
  • How the plant measures success? What are the key performance indicators?

The following metrics (site vs. industry) can be used as performance indicators for monitoring and trending:

  • Percent obsolete components;
  • Percent unidentified components;
  • Percent components with incomplete data;
  • Number of reactive obsolescence incidents per year during operation/ outage;
  • Total number of plant systems or components reviewed or un-reviewed (proactive approach);
  • Number of priority obsolete components in the backlog;
  • Number of days priority components have existed in the backlog;
  • Average closure time, i.e. the time between obsolete item identification and positive evidence of a solution;
  • Generation loss due to obsolescence;
  • Cancelled or deferred maintenance activities due to obsolescence;
  • Number of temporary modification (or non-conformity) in order to solve obsolescence problems; and
  • Number of days to implement a solution for an obsolete component.

Causalanalysis is usually implemented by all events that affect the safety or availability of the plant's production capacity.Technological obsolescence is an important parameter that is usually consideredupon evaluating the cause of the plant disturbance. The number of identified “obsolescence events” can be monitored as a plant performance indicator.

  1. Mitigating technological obsolescence:

Reactive or proactive obsolescence issues can be added to the plant’s corrective action programme with action plans and due dates. Codes areavailable for events that are caused by obsolescence or have obsolescence issues that result in an extension of outage so that the impact of technological obsolescence on plant availability can be fully understood.

For all action plans created, potential solution paths are researched. These solution paths apply to either a reactive obsolescence challenge or a proactive one. The following table represents the seven possible solution paths available for obsolescence, as well as what department/organization that may be involved in completing the resolution. The solution paths are listed in priority order least to most complex:

Solution Path / Responsible Organization
1. / Surplus market (open market quotes) / Supply chain
2. / Special manufacturing run / Supply chain
3. / Equivalent replacement / Procurement engineering
4. / Rebuild/repair / Plant engineering
5. / Utilization of parts from other components / Plant engineering
6. / Reverse engineering / Plant engineering
7. / Design change / Design engineering

The following describes each solution path:

  1. Surplus market – Though the original equipment manufacturer no longer manufactures anitem, existing inventories of the item may exist and the item may be available for purchase. There are suppliers who specialize in the purchase and resale of discontinued products or other power plants that have excess inventory. This is the least challenging solution as it provides identical components or parts to be procured in order to resolve the obsolescence issue.
  2. Special manufacturing run – Original equipment manufacturers are sometimes willing to manufacture the obsolete item for a specific quantity in order to provide a life of plant inventory of the obsolete item.
  3. Equivalent replacement – Another item is identified as a replacement for the item no longer available and an engineering analysis is performed to validate the interchangeability and impact to system performance for the replacement. Commercial grade dedication is a common acceptance process for equivalency replacement in which dedicated item is supplied in place of basic parts important to safety that was formerly available from original equipment manufacturer[9], [10], [11].
  4. Rebuild/repair - Some equipment can be placed on a long term service contract with a supplier or manufacturer that has the capability to provide spare parts in order to rebuild or repair equipment as necessary.
  5. Utilization of parts from other components– This solution path is a special case of the rebuild/repair option. Parts required to rebuild a component are scavenged from an identical spare that is typically not in operation.
  6. Reverse engineering – This solution path is the process of developing product specifications sufficient to duplicate an item by reviewing technical information and conducting physical examinations of an original specimen. Typically a third party supplier who is not the original equipment manufacturer performs this analysis and design with identical critical characteristics to remanufacture an item.
  7. Design change – This solution path refers to a plant modification to replace the item no longer available with a different item.

Further details, explanation, and examples can be found in [4],[5],[6] and [7].Components within the scope of the programme may be procured either as basic components or as commercial grade items and dedicated by the licensee in accordance with relevant national Quality Assurance programme, e.g. [9], [10], [11].

The following considerations may help to mitigate the technological obsolescence problems:

  • The correct analyses regarding spare parts and stock levels mitigate the obsolescence issue. When possible, advanced procurement process can ensure the operation for long time despite obsolescence issues;
  • Sharing information and solutions with other plants are actions to mitigate the effects;
  • Training and qualifying workers to perform repair service on obsolete item or to consider contract a specialized company to conduct repair service;
  • Keeping a database with information about which, where and how many parts are obsolete. It is constantly updated;
  • Improving maintenance to allow the lifetime extension of obsolete components;
  • Improving engineering support to analyze if a substitute can be applied;
  • Sharing obsolete components between others plants;
  • Selecting appropriate technology;
  • Using a standard equipment rather than customized or unique designs;
  • Identifying key components which are likely to become obsolete before the end of SSC lifetime and procurement of sufficient spare parts;
  • Keeping sufficient capacity to accommodate future need;
  • Using modular design so that obsolescence can be tackled on module basis;
  • Using configurable/ programmable design providing flexibility to accommodate changed need with a need of external support;
  • Enhancing the spares stock based on experience of spares consumption in the early stages itself;
  • Cooperating with other plants and organisations in order to support the availability of spare part and equivalent components; and
  • Getting access to the original equipment manufacturer specifications and procedures.
  1. Acceptance criteria:

The obsolescence programme acceptance criteria are: