16 Reliability Centered Maintenance - Springer Link

16 Reliability Centered Maintenance Atiq Waliullah Siddiqui and Mohamed Ben-Daya

16.1 Introduction The maintenance function must ensure that all production and manufacturing systems are operating safely and reliably and provide the necessary support for the production function. Furthermore, maintenance needs to achieve its mission using a cost-effective maintenance strategy. What constitutes a cost effective strategy evolved over time? In the past, it was believed every component of a complex system has a right age at which complete overhaul is needed to ensure safety and optimum operating conditions. This was the basis for scheduled maintenance programs. The limitation of this thinking became clear when it was used to develop the preventive maintenance program for the “new” Boeing 747 in the 1960s. The airlines knew that such a program would not be economically viable and launched a major study to validate the failure characteristics of aircraft components. The study resulted in what became the Handbook for the Maintenance Evaluation and Program Development for the Boeing 747, more commonly known as MSG-1 (Maintenance Steering Group 1). MSG-1 was subsequently improved and became MSG-2 and was used for the certification of DC 10 and L 1011. In 1979 the Air Transport Association (ATA) reviewed MSG-2 to incorporate further developments in preventive maintenance; this resulted in MSG-3, the Airline/Manufacturers Maintenance Program Planning Document applied subsequently to Boeing 757 and Boeing 767. United Airlines was sponsored by the US Department of Defense to write a comprehensive document on the relationships between Maintenance, Reliability and Safety. The report was prepared by Stanley Nowlan and Howard Heap (Nowlan and Heap 1978) it was called ‘Reliability Centered Maintenance'. The application of MSG-3 outside the aerospace industry is generally known as RCM. Afterwards, RCM spread to nuclear power plants and other industries. The studies in the airline industry revealed that scheduled overhaul did not have much impact on the overall reliability of a complex item unless there is a dominant failure mode. Also, there are many items for which there is no effective form of

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scheduled maintenance. In Figure 16.1, it is clear that only 11% of the components exhibit a failure characteristic that justify a scheduled overhaul or replacement. Eighty nine percent showed random failure characteristics for which a scheduled overhaul or replacement was not effective. Therefore, new thinking is required to deal with the remaining 89%. These findings redefined maintenance by focusing thinking on system function rather than operation. To understand better this shift in thinking and introduce a formal definition of RCM, the Society of Automotive Engineers has developed and issued SAE JA-1011, which provides some degree of standardization for the RCM process. The SAE standard defines the RCM process as asking seven basic questions from which a comprehensive maintenance approach can be defined: 1. 2. 3. 4. 5. 6. 7.

What are the functions and associated performance standards of the asset in its present operating context? In what ways can it fail to fulfill its functions? What causes each functional failure? What happens when each failure occurs? In what way does each failure matter? What can be done to predict or prevent each failure? and What should be done if a suitable proactive task cannot be found?

From these seven questions emerges a systematic process to determine the maintenance requirements of any physical asset in its operating context, called Reliability Centered Maintenance. The first step in the RCM process is to define the functions of each asset in its operating context, together with the associated desired standards of performance. Then identify what failure can occur and defeat the functions. Once each functional failure has been identified, the next step is to try to identify the causes of failures, i.e., all the events which are reasonably likely to cause each failure mode. These events are known as failure modes. The fourth step in the RCM process involves listing failure effects, which describe what happens when each failure mode occurs at the local and system level. The RCM process classifies these consequences into four groups, as follows: • • • •

Hidden failure consequences; Safety and environmental consequences; Operational consequences; and Non-operational consequences.

Identifying the consequences of failure helps in prioritizing the failure modes because failures are not created equal. By now the RCM process generated a wealth of information on how the system works, how it can fail, and the causes and consequences of failures. The last step is to select maintenance tasks to prevent or detect the onset of failure. Only applicable and effective tasks are selected. This way RCM can be used to create a cost-effective maintenance strategy to address dominant causes of equipment failure. It is a systematic approach to defining a preventive maintenance program composed of cost-effective tasks that preserve important systems functions.

Reliability Centered Maintenance

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The RCM framework combines various maintenance strategies including timedirected preventive maintenance, condition based maintenance, run-to-failure, and proactive maintenance techniques in an integrated manner to increase the probability that a system or component will function in the required manner in its operating context over its design life-cycle. The goal of the method is to provide the required reliability and availability at the lowest cost. RCM requires that maintenance decisions be based on clear maintenance requirements that can be supported by sound technical and economic justification. The purpose of this chapter is to provide an informative introduction to RCM methodology and is organized as follows: in the next section, RCM philosophy along with its principles, key features, goals and benefits are discussed. This is followed by discussion on background issues, including system, system boundary, interfaces and interactions. Section 3 talks about failure and its nature. Section 4 presents RCM methodology and practical RCM Implementation issues are discussed in Section 5. The last section concludes the chapter.

4%

2%

5%

7%

14%

68% Failure rate

Time

Percent of total

Figure 16.1. Aircraft failure characteristics (Nowlan and Heap, 1978)

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16.2 RCM Philosophy Reliability Centered Maintenance philosophy is based on a system enhancement method that keeps a cost effective view while identifying and devising operational, and maintenance polices and strategies. This is done in order to manage the risks of a system’s functional failure in an economically effective manner, and is especially applicable to situations where there are low or constrained financial resources. RCM philosophy fundamentally differs from other maintenance strategies, by preserving system functionality to a desired level, as opposed to maintaining equipments keeping it isolated with their relationship to the system. In summary, Reliability Centered Maintenance is a systematic approach to defining a planned maintenance program poised of cost-effective tasks while preserving critical plant functions. An important aspect of this philosophy is to prioritize systems by assigning levels of criticality based on the consequences of failure. This aspect, in particular, is in line with the fundamental objective of being cost effectiveness with efficiency channelizing the resources to the high priority tasks. This is done by identifying required design and operational modifications and justified maintenance strategies according to the priority levels. As an example, equipment that is non-critical to the plant may be left to run to failure while equipment serving critical functions is preserved at all cost. Maintenance tasks are selected to address the dominant failure causes addressing preventable failures through maintenance. RCM underlines the use of predictive maintenance (PdM) besides traditional preventive measures. 16.2.1 RCM Principles and Key Features There are four principles or key features that characterize the RCM process. These features are: 1.

2.

3.

4.

Preserving the system function is the first and principal feature of RCM process. This feature is important in its understanding. It must be stressed, as it forces a change in the typical view of equipment maintenance and replaces it with the view of functional preservation. What is required is to identify the desired system output and ensure availability of the same output level? Identification of the particular failure modes that can potentially cause functional failure is the second feature of RCM process. This information is crucial whether a design or operational modification is required or a maintenance plan is to be made. Prioritizing key functional failures is the third of the RCM process features. This feature is of foremost importance as the philosophy of efficiency with cost effectiveness can be achieved through this feature. Efforts and resources are dedicated to equipment supporting critical functions and their unavailability means major degradation of plant to even total shutdown. Selection of applicable and effective maintenance tasks for the high priority items is the fourth feature of the RCM process. As described earlier, the


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purpose of prioritizing is to make an efficient and cost effective use of resources. 16.2.2 RCM Goals and Benefits Various goals are served through RCM implementation. First, it helps determine the optimum maintenance program. It is also a proven and effective strategy in optimizing the maintenance efforts, both in terms of, operational efficiency and cost effectiveness. It helps keeping focal point on maintaining or preserving the most crucial system functions, while averting maintenance actions that are not particularly required. In essence it endeavors for the required system reliability at the lowest possible cost without forgoing issues related to the safety and the environment. Significant benefits are also tangible; these typically includes cost saving, shifting from time-based to condition-based work, spare parts usage reduction, improved safety and environmental conditions, improvement in workload reduction and operation performance, large information database enhancing the level of skill and technical knowledge. 16.2.3 System, System Boundary, Interfaces and Interactions A better understanding of RCM methodology requires understanding of few key systems definitions. This section briefly discusses such key terms. 16.2.3.1 Systems All systems are made up of three basic components. These are input, process and output. This is shown in Figure 16.2. The figure shown is also known as a basic system diagram which is one of the ways to model or represent any system.

Process Input

output Open loop system

Figure 16.2. Basic system diagram of an open loop system

The model of a system shown in Figure 16.2 is also known as an open loop system. An open loop system is defined as a system that has no feedback. As opposed to an open loop system, a closed loop system (Figure 16.3) uses a feedback to measure the output ensuring actual results seeking desired results. 16.2.3.2 Complex Systems Industrial systems are almost always complex in nature. The term complex systems refers to a system in which the elements are varied and have complex or convoluted relationships with other elements of the system. The systems which are not complex in nature generally involve fewer engineering disciplines, e.g., a

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washing machine is an electro-mechanical system. Examples of some complex technological systems, signifying the three basic components, are illustrated in Table 16.1.

Input

Process

output

Feedback Closed loop systems Figure 16.3. Basic system diagram of a closed loop system Table 16.1. Examples of complex system System

Inputs

Process

Outputs

Weather satellite Airlines ticketing system Oil refinery

Images, signals

Processed images

Travel requests

Data storage, processing and transmission Data management

Crude oil, catalysts, energy

Cracking, separating and blending

Petrol, diesel and lubricants etc.

Fuel (uranium), heavy water cargo request

Fission reaction, power generation map tracing, communication

Electric a.c. power Routing information, cargo delivery

Nuclear power plant road cargo system

Reservation and air tickets

16.2.3.3 Modeling a Complex System By character, complex systems can be made up of a number of major systems which are composed of further more simple working elements down to primitive elements such as gears, pulleys, buttons, resistors, and capacitors, etc. The architecture, also known as system block diagram (see Figure 16.4.), shows the structure and terminologies used to model a complex system (here a complex systems means a plant or a facility). As can be seen, the highest level is known as a plant having the largest scope. This is followed by a number of systems with smaller scopes. Collection of all these systems makes a plant or complex system. Each system is made up of components, and each component has a simpler functionality as compared to a systems. These components are the first to provide a significant functionality. For this reason, the components are considered to be the basic system building blocks.


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Plant

System 1

System 2

Component 1

Component 2

Part 1

Part 2

…

System x

… Component x

…

Part x

Figure 16.4. Architecture of a complex system

The main purpose of a system is to alter the three basic entities on which a system, generally, operates. These are information, material and energy, which provide us a good basis to classify principal functional elements. These are: 1. 2. 3. 4.

Signal (a system can generate, transmit, distribute and receive signals used in sensing and communication); Data (a system can analyze, organize, interpret, or convert data into forms that a user desires); Material (provide structural support for a system– it can transform shape or composition of materials, etc.,); and Energy (provide energy to a system).

Components are defined as physical embodiment of these functional elements which can be classified in six groups as shown in Figure 16.5. These six categories are electronic, mechanical, electromechanical, thermo-mechanical, electro-optical, and software. The lowest or the most primal level in a system is known as parts. A part in itself does not have any functioning but are required to put together components. Examples of parts are: electronic: LED, resistors, transistors; mechanical: gears, ropes, pulleys, seals; electromechanical: wires, couplings, magnets; thermomechanical: coils, valves; electro-optical: lenses, mirrors; software: algorithms etc. Interfaces and interactions There are three types of interface that may occur in a system. These are: 1.

Connectors: connectors facilitate the transmission of physical interaction, e.g., transmission of fluid through pipes or electricity through cables, etc.;

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2. 3.

Isolators: isolators impede or block physical interaction, e.g., rubber cover over copper wire, etc.; and Converters: converters alter the form of the physical medium, e.g., pump changes the force in a fluid, etc.

More examples of interfaces along with type of physical medium is given in Table 16.2. Electronic Mechanical Electromechanical Component Thermo-mechanical Electro-optical Software Figure 16.5. Classification of component Table 16.2. Examples of various types of interfaces Type

Electrical

(medium)

(current)

Mechanical (force)

Hydraulic

Human-

(fluid)

Machine (information)

Connectors Isolators Converters

Cable, switches Insulator Transformer, antenna

Cam shaft, connecting rod Bearing, shock absorbers Crank shaft, gear train

Value, piping Hydraulic Seal Pump, nozzle

Control display panel Window shield Software

16.3 Failure and its Nature Understanding of failure and its nature is at the core of understanding and implementing the RCM strategy. A look at this aspect is required before moving forward. Key definitions are presented below. Failure Failure of a component occurs when there is a significant deviation from its original condition that renders it unacceptable for its user. It can be categorized as


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complete failure, partial failure, intermittent failure, failure over time, or overperformance of function. Functional failure Functional failure on the other hand is defined as the inability of a system to meet its specified performance standard. Potential functional failure This is an identifiable physical condition that identifies an impending functional failure. Failure modes Failure modes are defined as the manner in which a failure may happen. It could be physical such as conditions where a part fails or conceptual where failure is not identified and organizational where absence of well defined job roles and mission priorities leads to failures. Reliability Reliability is the ability of a system or a component to perform its required functions consistently under the stated conditions for a specified period of time or in other words it is the capacity of a device or system to resist failure.

16.4 RCM Methodology RCM has a seven step methodology. This methodology warrants documentation that records exactly how maintenance tasks were selected and why these were the best possible selections amongst a number of competing alternatives. These seven steps include: 1. 2. 3. 4. 5. 6. 7.

Selecting systems and collecting information; System boundary definition; System description and functional block diagram; System functions and functional failure; Failure mode and effective analysis (FEMA); Logic decision tree analysis (LTA); and Task selection.

The next sections describe each of these steps. 16.4.1 Selecting Systems Selection and Collecting Information As discussed earlier, and by experience, system level analysis is the best approach; component level lacks defining significance of functions and functional failure, while plant level analysis makes the whole analysis readily intractable.

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Having decided that system is the best practical level for conducting such an analysis, the next question to confront is to choose what systems and in which order. One answer could be to select all systems within the plant or facility and in any order. However, this contradicts the sprit and the main drive of RCM – cost effectiveness. This argument is also supported by the fact that many systems neither have the history of consistent failures nor incur excessive maintenance costs that would justify the whole effort. As this may be a situation faced at most plants several selections schemes, that are employed, can be identified as follows: 1. 2. 3. 4. 5. 6. 7.

Systems with a large number of corrective maintenance tasks during recent years; Systems with a large number of preventive maintenance tasks and or costs during recent years; A combination of scheme 1 and 2; System with a high cost of maintenance of corrective maintenance tasks during recent years; Systems contributing significantly towards plant outages/shutdowns (full or partial) during recent years; Systems with high concern relating to safety; and Systems with high concern relating to environment.

It has been found with experience that all of these schemes except schemes 6 and 7 yield more or less the same results. What is a suitable scheme in a particular case is a subjective matter, but more importantly it should be done in as simplistic a way as possible with a minimal expenditure of time and resources. An indicator of decent selection is that systems chosen for an RCM program are easily pinpointed without a big margin of error. The next step, after selecting systems, is collecting information related to these systems. A good practice is to start collecting key information and document right at the outset of the process. Some common documents are identified that may be required in a typical RCM study. These are: • • • • • • •

P&ID (piping and instrumentation) diagram. systems schematic and/or block diagram (usually less messy than P&ID and facilitates better understanding of main equipment). Functional flow diagram (usually less messy than P&ID and facilitates better understanding of functional features of the system). Equipment design specification and operations manuals (a source of finding design specifications and operating condition details). Equipment history (failure and maintenance history in specific). Other identified sources of information, unique to the plant or organizational structure. Examples include industry data for similar systems. Current maintenance program used with the system. This information is generally not recommended to collect before step 7, in order to avoid and preclusions and biases that may affect the RCM process.


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16.4.2 System Boundary Definition The identification of a system depends on various factors. These may include plant complexity, governmental or regulatory rules and constraints, local and / or unique industry practices, a firm’s financial structure, etc. Although a gross system’s definitions and boundaries have been identified for specific cases, that may be used to good effect in step one as well but does not suffice for further analysis. Detailed and precise boundary identification is vital. Key reasons for this are: 1. An exact knowledge of what is included (conversely not included) in a system in order to make sure that any key system function or equipment is not neglected (conversely not overlapped from another equipment). This is especially important if two adjacent systems are selected. 2. Boundary definition also includes system interfaces (both IN and OUT interfaces) and interactions that establish inputs and outputs of a system. An accurate definitions of IN and OUT interfaces is a precondition to fulfil step 3 and 4. There are no clear rules to define system boundaries; however as a general guideline a system has one or two main functions with a few supporting functions that would make up a logical grouping of equipment. However the boundary is identified, there must be clear documentation as part of a successful process. 16.4.3 System Description and Functional Block Diagram The logical step to follow after system selection and boundary definition is to analyze further and document the necessary details of the systems under scope. This step generally involves form to document baseline characterization of a system that is eventually to be used in stipulating PM tasks. A typical form is shown in Figure 16.6. The five items established during this step are as follows: 1. System description In this step data already collected in earlier stages are put in the system analysis form. An accurate and well documented system definition will help produce concrete payback. This baseline information also serves as a record that will assist in comparisons during modifications and upgrades in the design or operations. It also identifies key design and operational parameters that directly affect the performance of the system functions. 2. Functional block diagram A system block diagram, as discussed previously (Figure 16.4.), deals with the static and physical relationship that exists in a system. It does not illustrate the more significant characteristics of a system such as the behavioral response that happens with the changes in the system environment. This behavioral response depends on the function that a system can perform to such environmental inputs and constrictions. To model this functional behavior a FBD or functional block

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diagram (Figure 16.7) is used. FBD elaborates functional flow in a system which is a top-level representation of the major function that a system performs. Arrows connecting blocks roughly represent interaction amongst functions and with the IN/OUT interfaces (to be adjoined in the next step). RCM System Analysis (system description) Date: Plant: Location: System Name: RCM Analyst(s): System ID: 1. System Location: 2. Functional Description Key Parameters Key equipment Redundancy Features Safety Features Figure 16.6. Typical RCM system analysis form

Figure 16.7 shows example of functional flow block diagram for a car temperature control system. The system has two main functions: temperature detection and cooling control. Each function is further explicated by FBD discretely. Temperature detection

Car temperature control system

Cooling system control

Figure 16.7. Functional flow block diagram

3. In/out interfaces After defining a system along with its boundary and major function we can define system interfaces. IN interfaces exist within a system while OUT interfaces exist at


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the boundaries of the system, making themselves the principle objects to preserve system functions. A point to note is that the IN interfaces might be OUT interfaces in some other systems. If an interface is within a system boundary connecting to system environment it is called the Internal OUT interface. Likewise, in step 3 a form is used to document interfaces (see Figure 16.8). RCM System Analysis (interface definition) Date: Plant: Location: System Name: RCM Analyst(s): System ID: 1. System Location: 2. IN interfaces OUT interfaces Internal OUT interfaces Figure 16.8. Typical RCM system analysis form for interface definition

4. Systems work breakdown structure Systems work breakdown structure or SWBS is a term used to identify a list of equipment/components for each of the function shown in a functional block diagram. This list is defined at the component level of assembly that resides with the system boundary. Identification of all components within a system is essential as otherwise it will eliminate these unlisted components out of the PM considerations. A typical SEBS form is shown in Figure 16.9. RCM System Analysis (System Work Breakdown Structure) Date:

Plant:

System Name: System ID: System Location:

Location: RCM Analyst(s): 1. 2.

Item

Number of item used

Non-instrumentation List Instrumentation List Figure 16.9. Typical RCM system analysis form for system work breakdown structure

5. Equipment history Equipment history is also recorded in a form as shown in Figure 16.10. It contains failure history that has been experienced during the last couple of years. This data can be obtained from work orders used for corrective and preventive maintenance.

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RCM System Analysis (Equipment History) Date: Plant: Location: System Name: RCM Analyst(s): System ID: 1. System Location: 2. Component Date Failure Mode Failure Cause

Figure 16.10. Typical RCM system analysis form for equipment history

16.4.4 System Functions and Functional Failure This step identifies the functions that are needed to be preserved by the system (at the OUT interfaces). An important point to note is that these statements are for defining system functions and not the equipment. With the definition of system functions comes the functional failures. In fact, failing to preserve a system function constitutes what is called a functional failure. This leads to the step of how a process function can be defeated. This requires two things; keeping the focus on the loss of function and not the equipment and that the functional failures are more than just a single statement of loss of function. The loss conditions may be two or more (e.g., complete paralysis of the plant or major or minor deprivation of functionality. This distinction is important and will lead to the proper ranking of functions and functional failures. 16.4.5 Failure Mode and Effective Analysis (FEMA) Failure Modes and Effects Analysis (FMEA) is a fundamental tool used in reliability engineering. It is a systematic failure analysis technique that is used to identify the failure modes, their causes and consequently their fallouts on the system function. As discussed in Chapter 4, identifying known and potential failure modes is an important task in FMEA. Using data and knowledge of the process or equipment, each potential failure mode and effect is rated in each of the following three factors: • Severity – the consequence of the failure when it happens; • Occurrence – the probability or frequency of the failure occurring; and • Detection – the probability of the failure being detected before the impact of the effect is realized. Then these three factors are combined in one number called the risk priority number (RPN) to reflect the priority of the failure modes identified. The risk priority number (RPN) is simply calculated by multiplying the severity rating, times the occurrence probability rating, times the detection probability rating.


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FMEA process is usually documented using a matrix similar to the one shown in Figures 4.1–4.3 (see Chapter 4 for more details). For each component, the failure modes are listed, their causes are identified, and their effects are determined. This initial screening of the failure modes help to prioritize them. Further prioritization will be conducted in the next step using logic tree analysis. 16.4.6 Logic or Decision Tree Analysis (LTA) Logic tree or decision tree analysis (LTA) is the sixth step in RCM methodology. The purpose of this step is to prioritize further the resources that are to be committed to each failure mode. This is done since each failure mode and its impact on the whole plant is not the same. Any logical scheme can be adopted to do this ranking. RCM processes a simple and intuitive three question logic of decision structure that enables a user, with minimal effort, to place each failure mode into one of the four categories. Each question is answered yes or no only. Each category which is also known as bin forms natural segregation of items of respective importance. The LTA scheme is shown in Figure 16.11. This makes items fall in the categories of A, B, C, D/A, D/B or D/C. For the priority scheme, A and B have higher priority over C when it come to allocation of scarce resources and A is given higher priority than B. In summary, the priority for PM task goes in the following order: • A or D/A; • B or D/B; and • C or D/C. 16.4.7 Task Selection In this step, we have to allocate PM tasks and resources and this is the point where we would be able to reap the maximum economic benefits of RCM activity. The task selection requires that each task is applicable and effective. Here, applicable means that the task should be able to prevent failures, detect failures, or unearth hidden failures, while effective is related to the cost effectiveness of the alternative PM strategies. If no PM task is selected the only option is to run equipment to failure. This activity requires contribution from the maintenance personnel as their experience is invaluable in the right selection of the PM task.

16.5 RCM Implementation The practical side or implementation of RCM is an important factor to look at since; typically, such a program will initially focus on its planning and completion of systems analysis phase. However, in reality the real complexity that is almost always present in planning and coordination phases of such efforts is hard to realize before it catches up. This immediately results in delays and problems in communication, decision and consequently in the execution of the project. In this

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case certain practical guidelines present in RCM reference have been summarized below. Failure modes

Is the operator aware of something occurring under regular conditions? D Does this failure mode caused a safety issue?

Hidden failure (requires return to logic tree to see if the failure is an A, B, C)

A Is there a full or partial outage of the plant

Safety issue

by this failure mode?

B

C Outage issue

Minor or economically insignificant issue

Figure 16.11. Logic tree analysis

16.5.1 Organizational Factors Organizational factors play an important part as they define responsibilities and jurisdictions, and establish communication channels essential for such an effort. Issues that are needed to be addressed are: 1.

2.

Company organization: although, a prime factor in the success of any such concerted and complex effort requires motivation and strong personalities, a loose organizational structure with unclear responsibilities’ and loose communication channels proves to be a major hurdle in making any such effort a success. With goo team work, where there is top management commitment and clear organizational hierarchy, the already complex task is not further aggravated, and this setup rather supports and simplifies the project handling. In RCM a key success factor is the separation of production and maintenance functions with clear peer like coordination. The decision making process: any large scale and complex successful projects is driven by commitment from the management, both at the top and at plant level. This becomes even more essential as such initiative demands a change


3. 4.

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in a company’s cultural and major operational methodologies, resulting in phenomena such as internal resistances and lack of employee commitment and motivation. This may prove to be a real threat as resulting quality compromise renders the whole process futile. The financial aspect: financial commitments are required while unforeseen costs may appear. Major cost factors include training, consultation fees, software support, project facilitation cost, etc. Project ownership (The Buy-in Factor): buy-in process signifies a process where individuals or teams responsible for implementation are made part of the planning and development process, creating a sense of ownership. This proves to be a motivating factor which contributes towards removing project hurdles and success.

16.5.2 RCM Teams RCM team formation is another issue that is almost always present in RCM projects. Availability of experienced personnel and on-site plant staff with the present work load are some of the issues to handle, especially for keeping the buyin factor in view. Various resource allocation strategies are mentioned in the literature; one good strategy is to assign appropriate on site personnel to the RCM team by giving it top priority over other activates. Another strategy is to increase plant staffing if current staffing is not committed. A third strategy is to commit a team from corporate head quarters and a fourth strategy is to outsource or contract the RCM project. As for the team formation, a typical team comprises four to five members with a facilitator. Diverse experience proves healthy for the team. The facilitator in the team is generally responsible for the coordination of efforts and guides in achieving buy-in during the early stages of the projects. 16.5.3 Scheduling Consideration and Training Scheduling considerations also play a key role in RCM success. Lack of dedicated allocation of team personnel and other resources severely hinders project deadlines and this is common in such situations. The scheduling considerations not only involve project management aspects and logistics but they must include a timeframe that would enable the organization to pass through the learning curve that is needed in the change in the mindset and culture. The schedule must also include a pilot project. Training is also required with a firm grip on RCM philosophy, seven step methodology and; a good knowledge of practical issues and understanding of the current maintenance situation, etc. Generally, training for RCM is carried out in a two step method form. In the initial step, a classroom setting for training works well, with a session of 3–5 days, while hands-on training cannot be avoided due to the nature of the process. This hands-on training is best done under the guidance of a trained person generally available as facilitator of the project. The important aspects to keep in mind include how to get acquaintance and documentation of the current maintenance situation, the knowledge of RCM, its methodology, and in

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what ways RCM would help the plant in terms of cost effectiveness and plant efficiency.

16.6 Conclusion A brief description of RCM is presented in this chapter. The objective was to introduce the reader to the basics of RCM. The methodology has proved time and again to deliver fruitful results. However, in spite of the simplistic and intuitive appeal, application without full understanding may lead to project hiccups if not total failures. A detailed pre-study is required before such an initiative should be undertaken. One should be careful that the initial simplistic appeal of the methodology should not make a user unsighted to the real application issues and challenges. A lack of experience as RCM implementers and/or people providing necessary information may hinder in the success of the project. Management’s direct interest is always crucial and any such activity should not be undertaken until or unless there is full support, commitment and involvement from both top and plant management. Buy-in is a factor that should never be forgotten. With cultural and fundamental work methods changes at hand, buy-in is a proven strategy to confront internal and cultural resistances. With a learning curve required to grasp fully the philosophy of method, initial investments on training also serves well. RCM is a highly intuitive and applicable method. Its philosophy and methodology was discussed along with implementation issues and challenges. Deciding to use this methodology with a good handling of implementation challenges ensures considerable efficiency and economic benefits.

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Nowlan FS, Heap HF (1978) Reliability Centered Maintenance, United Airlines Publications, San Francisco, CA. Smith AM and Hinchcliffe GR (2004) RCM gateway to world class maintenance. Burlington : Elsevier Butterworth-Heinemann.