Asset Integrity Management and Other Concepts of Asset Reliability

Asset Integrity Management and Other Concepts of Asset Reliability

7 ASSET INTEGRITY MANAGEMENT AND OTHER CONCEPTS OF ASSET RELIABILITY CHAPTER OUTLINE Introduction 273 Definitions of reliability 273 Measurements of r...

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7 ASSET INTEGRITY MANAGEMENT AND OTHER CONCEPTS OF ASSET RELIABILITY CHAPTER OUTLINE Introduction 273 Definitions of reliability 273 Measurements of reliability 274 Reliability index 274 Asset integrity management 274 Risk-based inspection 275 RBI for refineries and chemical plants 276 Reliability centered maintenance definition 277 Limitations of RCM approach 278 Steps for implementing RCM 278 Selection of equipment for RCM analysis 279 Setting the boundary and function of the systems that contain the selected equipment 279 Risk-based maintenance definition 280 Determining risk 281 Risk assessment process for RBM 281 Total productive maintenance 282 Workforce participation 282 Total maintenance system 283 First phase 283 Second phase 284 Value-driven maintenance 284 Value on asset utilization 285 Value on Safety, Health & Environment 285 Cost control 286 Value from resource allocation 286

Pipeline Integrity. Copyright © 2017, 2014 Elsevier Inc. All rights reserved.




Evidence-based asset management 286 Component replacement 287 Inspection decisions 287 Capital equipment service life decisions 288 Resource requirements 288 Summary 288


Introduction A company’s assets include much more than maintenance management; it consists of all of the following. • The equipment it holds • The trained and efficient personnel that work there • Its very brand name • Company’s public image • Its stock values Thus the concept of asset management is an essential part of corporate management. The concept although is technical in nature, it is driven more by the economics and financial side of the management. This makes it pertinent that we understand what is the meaning of asset management? In its simplest explanation, it is possibly another word for maintenance of equipment and facilities, albeit by using modern data collection and analysis through artificial intelligence. But it may not be that simple; looking from another view, the asset management includes much more than maintenance management software. It is far beyond the role and function of a maintenance manager. The word “reliability” in terms of maintenance conveys the efforts taken to constant improvement initiatives. Several concepts include reliability-centered maintenance (RCM), reliability-based maintenance (RBM), etc. are derived from that understanding. In this chapter an effort is made to introduce those concepts.

Definitions of reliability The meaning of reliability is related to the value of trust, of being able to be trusted to do what is expected or has been promised. It can be defined as the probability that a component or system will perform a required function for a given time when used under stated operating conditions. The dictionaries describe reliability with adjectives such as dependability, trustworthiness, and consistency. With that definition the concept of reliability can be assigned to every aspect of the activity in business, the services provided, the product sold, production process that includes the reliability of the plant, and machinery to consistently produce the quality of goods. This is also referred as the production process reliability. For the process to be reliable, the reliability of the process equipment and their maintenance takes the main stage. Operations focuses on reliable process and maintenance focuses on reliable equipment. This requires that the operations and maintenance departments must have one common performance measurement.




Measurements of reliability If reliability is deemed as an indicator of confidence in a system or of an equipment, then there should be some way to know how reliable the system is. There should be a way to measure it. Reliability of any system can be quantified. From the definitions stated above, we can safely say that reliability is the combination of the quality of performance, which is one of the components of the reliability, the time it takes to produce reliable results, and the repeatability of that quality performance. It brings us to the following relationship: Reliability is: quality performance  time performance  speed performance. The most common way to measure overall production reliability is to measure quality, time, and speed performance. Time performance must include all available hours; for example, 8760 h in a year less market-related downtime and time for capital rebuilds.

Reliability index Another way to measure overall production reliability is the reliability index. For this the information about the production calendar time, number of production losses, and total production losses including losses in quality, time, and speed is required. In summary, the reliability index says that operation continues as long as possible without losses; and when there are losses, the restart time is as short as possible. Reliability index ¼ MTBPLyMPL; where MTBPL denotes mean time between production loss (time running/number of production losses) and MPL denotes tons lost/number of production losses.

Asset integrity management The goal of asset management is to effectively manage corporate assets to gain maximum value, increase profitability and returns on investment, while safeguarding the personnel, the community, and the environment.


A true asset integrity management (AIM) program starts from the concept of the system and includes the following: • design, • construction, • materials, • process, • operations, • maintenance, • inspection, and • the corporate management philosophy. All the above disciplines have a significant impact on the integrity of infrastructure and equipment. The successful implementation of asset integrity is based on the following and conducting essential elements. Elements of AIM: • Corporate business and financial modeling, • Management strategies, • Inspection use of relevant and up-to-date technologies, • Risk assessment, risk prioritization, and risk-based inspection (RBI), • Maintenancedreliability, predictive, and preventive strategies, • Operational and process support (critical operating and process windows), • Process safety and mechanical integrity services, • IT support/software tools, • Health, Safety and Environment strategies, and • Training in safety, industry codes, standards, and regulations. AIM tools may include: • RBI, • failure analysis services forensic engineering, • risk assessment, • hazard identification, • technical inspections, including where use of 3D scanning of equipment is possible, • dimensional control, • asset optimization, • life-cycle analysis, • surveying and mapping of assets, and • nondestructive testing and inspection.

Risk-based inspection Some of the above tools are discussed in the previous chapters of this book, including prioritizing the inspection schedule based on




the risk; however, the concept of risk-based inspection, often referred by its acronym RBI, is specific to AIM, and we will discuss it further. Both ASME and API have specifications and guidelines published on how to approach with his concept and how to implement it in refineries and elsewhere as applicable.

RBI for refineries and chemical plants Unplanned shutdowns of refineries or chemical plants can be minimized or avoided by using the concept of RBI and software developed based on that concept. The approach minimizes downtime and ensures equipment longevity for refinaries and chemical plants. The software is designed to analyze fixed equipment, piping, pipelines, and pressure relief devices. Thus the effectiveness of plant’s mechanical integrity inspection program is increasing, while minimizing risk to HSE and maximizing resource utilization. Key benefits of RBI: • provide a cost-effective alternative to traditional inspection, • establish better reliability of equipment and plant operation, • identify the operational risks associated with equipment, • comply with regulatory codes for increased safety, and • reduce plant downtime. Equipment reliability, along with efficient operation of aging infrastructure, is key to success in the refining industry; more refiners are making RBI a key part of their integrity management process. RBI is based on the prioritizing risk, and based on that it schedules and manages the in-service inspection program. The use of RBI refocuses and controls the cost, while focusing on the use of vital resources on the most needed basis. The inspection dollars and critical efforts are trained on the areas that are most needed. This is accomplished by utilizing technology that considers the probability and subsequent consequences of an unwanted event. A large percentage of risk in an operating plant is related to a small percentage of the equipment. RBI shifts inspection and maintenance resources to provide a higher level of coverage on high-risk items and the proper coverage on low-risk items. With RBI, the plant managers have the ability to increase run lengths of process facilities while reducing or maintaining the level of risk. The methodology and software developed by the API Joint Industry Project has become the industry standard for implementing RBI.


Several softwares are developed on RBI. Those softwares meet the requirements of the inspection part of the API 580, which is a qualitative RBI approach, while the methodology of RBI is described in API 581. The inspection approach tends to be subjective to consistently quantify risk and create a reproducible inspection planning process. The primary goal, however, should be to produce probability of failure, consequence of failure (COF), and risk values that can be trusted. This is possible when the software is based on API 581 methodology principles. The software should continually be updated as new technology is developed, standardized, and tested against API 581 for accuracy. In this respect the API RBI software is advantageous since it is documented in the public domain, allowing users to review and understand the calculated results and follow recommendations. The integrity of asset is not fixed to RBI alone, taking the result of the RBI software and integrating it with other concepts, such as fitness for purpose material selection, corrosion environment, failure mode analysis, and other tools described above, make the AIM program a formidable tool. Such approach to AIM helps to make decisions on remaining life of the equipment and finally to make critical decision on whether to replace an aging equipment or, upgrade its design, or replace with a new equipment. RBI systems are designed to analyze the data for fitness for service, corrosion and metallurgy, mechanical integrity, and RCM programs and applications. Some of these topics are discussed in previous chapters of the book. We would however discuss the RCM and other concepts that are linked to it.

Reliability centered maintenance definition RCM is a corporate level maintenance strategy that is implemented to optimize the maintenance program of a plant or facility. The final result of an RCM program is the maintenance strategies that should be implemented on each of the assets of the facility. The maintenance strategies are optimized so that the reliability is established that the plant would continue to function effectively. Equipment are maintained using costeffective maintenance techniques, of which RBI discussed above is one of the tools. RCM is based on the following principles that are critical for the effective implementation of RCM program. • The primary objective is to preserve system function • Identify failure modes that can affect the system function • Prioritize action to prevent or control identified failure modes




Equipment reliability and availability, achieved by minimizing the probability of system failure, is the focus of RCM. With this maintenance strategy, the function of the equipment is considered, and possible failure modes and their consequences are identified. Maintenance techniques that are cost-effective in minimizing the possibility of failure are then determined. The most effective techniques are then adopted to improve the reliability of the facility as a whole. For effective implementation of RCM, answers are sought for a series of functional questions about the facility. These answers contribute to the success of the facility. The focus is on the reliability, rather than the functionality, of these systems that are considered. The key questions that need to be asked for each asset are: • what are the functions and desired performance standards of each asset? • how can each asset fail to fulfill its functions? • what are the failure modes for each functional failure? • what causes each of the failure modes? • what are the consequences of each failure? • what can and/or should be done to predict or prevent each failure? • what should be done if a suitable proactive task cannot be determined? RCM identifies the functions of the plant or refinery that are most critical and then seeks to optimize their maintenance strategies using applicable and cost-effective techniques. The most critical assets are those that are likely to fail often or have large consequences of failure.

Limitations of RCM approach RCM does not readily consider the total cost of owning and maintaining an asset. Additional costs of ownership, such as those considered in evidence-based maintenance, are not considered and are therefore not factored into the maintenance considerations.

Steps for implementing RCM There are several different methods for implementing RCM, which are recommended by different organizations. In general, however, they can be listed in sequence as following.


Selection of equipment for RCM analysis The first step is to select equipment for RCM analysis. The equipment selected for RCM should be critical, in terms of its effect on operations, its previous costs of repair, and previous costs of preventive maintenance.

Setting the boundary and function of the systems that contain the selected equipment The equipment belongs to a system that performs certain function that is important to the process. Irrespective of the size of the system, the function of the system should be known as its inputs and outputs. 1. Identify the hazards that can lead to failure (HAZID) As the HAZID is conducted, it is also important to identify various modes of failure that can put the system out of service. 2. Conduct a root cause analysis of the failure modes With the help of operators, experienced technicians, RCM experts, and equipment experts, the root causes of each of the failure modes should be identified. 3. Assess the consequences of failure In this step the consequences of each failure mode are considered. This should include the effects on safety, operations, and other equipment. Criticality of each of these failure modes can also be considered. There are various recommended techniques that are used to give this step a systematic approach. These include: • failure mode and effects analysis, • failure mode, effect, and criticality analysis, • hazard and operability studies, • fault tree analysis, and • RBI. The most important failure mode is determined at the conclusion of the systematic analysis of each failure mode. This is done by asking questions such as: 1. does this failure mode have safety implications? and 2. does this failure mode result in a full or partial outage of operations? These important failure modes are then prioritized for further analysis. Importantly, the failure modes that are retained for further consideration include only those that have a real probability of occurring under realistic operating conditions.




4. Decide on the maintenance approach to deal with each failure mode At this step, the most appropriate maintenance tactic for each failure mode is determined. Importantly, the maintenance tactic that is selected should be technically and economically feasible. • Condition-based maintenance is chosen when it is technically and economically feasible to detect the onset of the failure mode. • Time or usage based also called the “preventative maintenance” is selected when it is technically and economically feasible to reduce the risk of failure using this method. • For failure modes that do not have satisfactory conditionbased maintenance or preventive maintenance options, a redesign of the system to eliminate or modify the failure mode should be considered. • Failure modes that were not identified as being critical through maintenance approach or RCA be identified as good candidates for a run-to-failure schedule. 5. Implement and monitor the selected maintenance approach Importantly, the RCM methodology will only be useful if its maintenance recommendations are put into practice. When that has been done, it is important that the recommendations are constantly reviewed and renewed as additional information is found.

Risk-based maintenance definition The risk-based maintenance (RBM) is the corollary of RBI. An RBM strategy prioritizes maintenance resources toward assets that carry the most risk if they were to fail. It is a methodology for determining the most economical use of maintenance resources. This is done so that the maintenance effort across a facility is optimized to minimize the total risk of failure. An RBM strategy is based on two main phases: 1. risk assessment and 2. maintenance planning based on the risk. The maintenance frequency and type are prioritized based on the risk of failure. Assets that have a greater risk and COF are maintained and monitored more frequently and on a priority basis. Assets that carry a lower risk are subjected to less stringent maintenance program. By this process, the total risk of failure is minimized across the facility in the most economical way.


The monitoring and maintenance programs for high-risk assets are typically the condition-based maintenance program described above. RBM is a suitable strategy for all maintenance plants. As a methodology, it provides a systematic approach to determine the most appropriate asset maintenance plans. Upon implementation of these maintenance plans, the risk of asset failure will be acceptably low.

Determining risk The RBM framework is applied to each system in a facility. A system, for example, may be a high-pressure vessel. That system will have neighboring systems that pass fluid to and from the vessel. The likely failure modes of the system are first determined. Then, the typical RBM framework is applied to each risk. The framework is shown in Figure 3.7.1. In earlier chapters we have identified the importance of the need for data collection for determining risk. Same principles of risk and consequences apply for risk evaluation and risk ranking for selecting suitable inspection process and initiating mitigation steps.

Risk assessment process for RBM Risk of failure assessment is one of the key steps in the application of RBM process. The accuracy of the assessment determines the final outcome of the maintenance process.

Figure 3.7.1 Risked-based maintenance framework.




There are several ways to assess risk, but there is no specific fits-all method that can be prescribed. Approaches like qualitative, semiquantitative, and quantitative are used to determine if the possible risks. Other estimation methods could be described as deterministic and probabilistic approaches. The most appropriate approach will depend on the data that are available to evaluate each risk.

Total productive maintenance Another maintenance philosophy is called total productive maintenance (TPM) that requires the total participation of the work force. It was first developed and implemented in Japan. TPM incorporates the skills and availability of all employees to focus on improving the overall effectiveness of a facility. Effectiveness is improved by eliminating the wastage of time and resources. Typically, TPM is a concept that is most easily applied to a manufacturing facility. TPM emphasizes all aspects of production. As such it seeks to incorporate maintenance into the everyday performance of a facility. To do this the maintenance performance is one factor that is considered when evaluating the performance of the facility. One of the most important measurements of TPM is overall equipment effectiveness (OEE). It is a measure of availability, performance efficiency, and quality rate. As such, equipment stopping, equipment working at less than peak capacity, and equipment producing poor quality products are all penalized when the OEE is determined. OEE ¼ availability  performance efficiency  quality rate.

Workforce participation To improve the OEE, total workforce participation is expected for a proper implementation of TPM. This includes everyone from the top level management to the equipment operators. • Top level management is expected to be involved by promoting TPM as a corporate policy and to make decisions based on OEE. To do this, they need to develop relevant metrics of TPM, such as OEE. • Operators are expected to take responsibility for the day-today maintenance of their machines. This includes the cleaning and regular lubrication necessary for equipment health. Operators are also expected to find early signs of equipment wear


and tear, deterioration and report them appropriately for necessary in-time repairs. They are also encouraged to determine ways to improve equipment operation. • Maintenance staff are expected to train and support operators to meet their goals and perform the more advanced preventative maintenance activities. They are also expected to take responsibility for improvement activities that will increase the OEE of the facility. The three levels are expected to work together toward TPM. Without cooperation it is likely that an implementation of TPM will fail.

Total maintenance system TPM requires a focus on the total maintenance system, from equipment design to asset maintenance strategies. • As far as possible the equipment is designed to be maintenance free. • All possible options must be considered to improve the maintenance techniques. • Preventive and predictive maintenance strategies should be implemented to eliminate reactive maintenance. TPM system is built on two phases. In the first phase, the 5S is the platform. The second phase is built on the seven pillars of TPM. These are built upon the 5S platform.

First phase The platform for TPM is the “5S.” Originally these are five Japanese phrases. 1. seiri, 2. seiton, 3. seiso, 4. seiketsu, and 5. shitsuke. All beginning with letter “S,” but phrases are translated in English starting with letter S. All five phrases are related to the place where production activity is occurring and are most obvious for the operators of the equipment. • Sort (Seiri)dDetermine which items are used frequently and those that are not. The ones used frequently should be kept in easy reach, close-to-hand, and not so frequently used items should be stored further away. • Systemize (Seiton)dEach item should have one place and only one place of storage.




• Shine (Seiso)dThe workplace needs to be well lighted and clean, without it problems will be more difficult to identify and maintenance will be more difficult to perform. • Standardize (Seiketsu)dThe workplace should be standardized and labeled. • Self-discipline (Shitsuke)dEffort should be made to continually perform each of the other steps described above at all the times.

Second phase 1. Autonomous maintenance: Operators are required to attend to the day-to-day maintenance of their equipment, without engaging the dedicated maintenance team. 2. Workforce should focus on improvement. 3. The approach is for the planned maintenance as opposed to the reactive (emergency) maintenance. 4. Quality of maintenance. 5. Education and Training. 6. Safety, Health and Environment (SHE) should be the driving force. 7. Office TPM. At the beginning of a TPM program the focus will be on the 5S and on developing an autonomous maintenance plan. This will free the maintenance staff to begin larger projects and perform increasing amounts of planned maintenance.

Value-driven maintenance Yet another concept of efficient maintenance program is called value-driven maintenance. Improper and poor maintenance deteriorates assets over time reducing the reliability of the production process and causing a knockdown effect on the quality of the product. It can also impact the safety of the asset or the people who operate it. Traditionally, maintenance has been viewed as a cost center in an organization; it costs money to hire maintenance technicians and purchase the spare parts to keep systems running smoothly. Often short sighted, senior executives ignore the added value that a good maintenance program brings to the organizations’ integrity. • Significance of cost savings from that of reactive maintenance costs • Reducing costs to restart production after a breakdown • Limiting production scrap


• • • •

Costs of downtime such as missed orders and lost revenue Customer perception/satisfaction Improved quality of products Reduced environmental impact Not surprisingly, maintenance can add economic value to a business by delivering maximum availability at the lowest possible cost. To view maintenance as a value driver, senior executives must move from cost-based thinking to value-based thinking. Value Driven Maintenance (VDM) is a methodology developed by Mark Haarman and Guy Delahay, for optimizing the value derived from maintenance at any particular point in time. The decision to perform maintenance at any time is based on the cost-benefit analysis. It requires a delicate balancing between the value that improved reliability can bring and the cost of maintenance. This is summed up in four value drivers.

Value on asset utilization Availability of the asset is the probability a system is functioning when needed to under normal operating conditions. When the system is alive and well, the organization can continue to produce output and meet orders. Increasing availability means more units can be produced with the same equipment, generating more income while fixed costs remain unchanged. This scenario is ideal in growth markets where demand outstrips supply. For declining markets, increasing asset utilization in one facility could lead to shutting down a sister plant while still meeting demand.

Value on Safety, Health & Environment Can we put a price on safety? The emphatic answer is “No,” we cannot put a price on safety of personnel. An effective SHE policy is an important value driver for maintenance; if not done properly, it can have a significant negative effect on future cash flows. Maintenance-related incidents that injure personnel, damage equipment, or cause negative impact on the environment will increase expenditure through litigation or imposed government penalties. A good SHE policy ensures that the license to operate remains intact. Losing the license to operate means no income. The BP’s Deepwater Horizon accident is one example that underlines the importance of good SHE policy and the enormous impact it can have on costs when it goes wrong.




Cost control Cost of reactive maintenance budget is increased by salaries, contractor fees, parts, emergency shipments, and specialist tools. Reducing reactive maintenance cost and limiting the need for external contractors, emergency parts procurement and shipments, and technician overtime can reduce the cost of maintenance and increase value to the asset. This requires careful planning to determine the optimum time to perform costeffective preventive maintenance. An effective preventive maintenance program can over the time increase the time between the maintenance and achieve further cost savings.

Value from resource allocation Prioritized resource allocation focuses on smarter management of limited and expansive resources. For example, smarter inventory management such as just in time and standardization can minimize stock on hand, which drives down the carrying costs and reducing the impact of part obsolescence; all these acts increase the value for a company. The challenge for maintenance planners would be to ensure that there are adequate resources when needed for preventive or reactive maintenance. The challenge for maintenance managers is to reduce related costs while improving or at least maintaining the reliability; but depending on priorities, this does not always maximize value. In the oil and gas industry, the SHE factor is critical. In highly competitive industries, such as consumer electronics, cost control takes center stage. Value can also depend on time. For example, during the recent downturn, the auto industry switched focus to cost control as demand crashed. This meant less preventive and reactive maintenance and leaving systems down for longer periods until repairs can be completed economically. As orders picked up, the focus switched from cost control to asset utilization.

Evidence-based asset management Evidence Based Asset Management (EBAM) is the science of making the right decisions and optimizing asset management processes with the best available data and with decision criteria clearly defined. Asset management in the past was not viewed as a professional activity. The critical maintenance decisions were based on personal experience, technician complaints, original


equipment manufacturer recommendations, hunches, and, the worst of all, the strength of personality. Within EBAM, common sense and expert judgment play a role but key asset decisions are based on solid evidence. Data-driven decisions in EBAM provide the most advantageous methodology for minimizing costs and maximizing the return on investment from physical assets. Making EBAM datadriven decisions requires access to maintenance and financial data; therefore, accurately logging maintenance activities is critical. There are four key asset management decision areas that are described below.

Component replacement The first area includes the determination of the optimal replacement time for spare parts. The decision is made to either replace components proactively, time-sensitive decision, or simply to run the component to fail. Replacing before failure ensures that the repairs can be planned in advance; but if the cost of reactive maintenance is less and there is no risk of collateral damage, then run-to-fail is the logical choice. Coupled with this decision is the determination of inventory levels for stock to complete repairs. The levels of stock on hand should ensure that availability and cost criteria are met.

Inspection decisions Optimizing the time interval between maintenance inspections can minimize the cost of preventive inspections and breakdown maintenance (Figure 3.7.2). Inspections should be performed where the total cost of maintenance is minimized.

Figure 3.7.2 PM optimizationdfoundation.




Figure 3.7.3 Economic life of assets.

Capital equipment service life decisions The economic life, also called as service life or useful life, is the expected period for which an asset is fit for purpose. The physical life of an asset could be considerably longer than the economic life. Without careful analysis, it is possible to confuse the two. Economic life of the asset (Figure 3.7.3) occurs when the total cost of ownership is at a minimum. According to EBAM principles, at this point, the asset should be replaced. Organizations must ensure that they have sufficient funds to purchase replacements at this point to reap potential savings. Other considerations such as technical improvement on newer models must also be factored into this decision area.

Resource requirements The final area involves right sizing maintenance crews, machine shops, tooling, and contractor labor to achieve productivity, system availability, and cost targets.

Summary In capital-intensive industries, asset management is making a fundamental shift from reactive to proactive maintenance coupled with a focus on the total cost of ownership. EBAM is a logical approach to maximize the return on investment on physical assets and strengthen the bottom line. EBAM provides direction on how to cost effectively manage assets while maximizing availability.