Implementation of rcm reliability focused maintenance

Reliability Centered Maintenance RCM is a systematic, objective and documented analysis methodology that can be applied to any type of industrial installation, useful for the development or optimization of an efficient maintenance plan. Developed by United Airline of the United States, the RCM analyzes each system and how it can functionally fail. The effects of each failure are analyzed and classified according to the impact on safety, operation and cost. These failures are estimated to have a significant impact on the subsequent review, to determine the root causes.

The central idea of ​​RCM is that maintenance efforts should be directed towards maintaining the function performed by the equipment rather than the equipment itself. It is the function performed by a machine that is of interest from the productive point of view. This implies that you should not seek to have the equipment as if it were new, but in sufficient condition to perform its function well. It also implies that the conditions under which this function is performed must be known in great detail and, above all, the conditions that interrupt or hinder it, the latter being the failures.

The global analysis process of the RCM is summarized as follows:

1. Analysis of functional failures. Defines the operation of the component in an equipment, its functional failure, and its failure effects. Selection of critical items. Determine and analyze which components and systems are characterized as functionally significant. RCM logical decision. It includes the analysis of the functionally significant items (IS), to determine the consequence of the failure. Inspection analysis. The inspection determines what data is necessary to support the RCM analysis. Summary of maintenance requirements. It determines the grouping of the optimal requirements of the level of maintenance that is practiced.

Preliminary Aspects of RCM Reliability Centered Maintenance

Reliability-Centered Maintenance RCM, as a structured analysis tool based on the specific information of the equipment and user experience, tries to determine which maintenance tasks are the most effective, thus improving the functional reliability of the related systems with security and availability, preventing failures and minimizing maintenance cost.

To carry out the RCM implementation, they must be sustained according to a defined RCM plan and the additional procedures shown in this paper.

Summary of tasks.-

The requirements of the tasks are the result of the analysis of the RCM that can have varying ranges. Tasks should be summarized in groups, with the aim of achieving various tasks in the team, whenever the team is in a maintenance program. Summarized the tasks, the levels and maintenance intervals in the work areas are considered.

Task processes.-

The first thing is to convert the task intervals into a common base measure (usually time). All tasks are displayed over time to see if there are natural groupings. The adjustment of the maintenance task intervals is carried out with the objective of grouping maintenance tasks, these groups must be recorded to make comparisons, redesign and determine the most convenient processes of the fixed maintenance.

Tool Considerations.-

The following considerations are requirements for conducting a maintenance program:

• Group all the work requirements in a specific area, especially if you have wasted time; However, if a work area with too many maintenance personnel is excessively loaded it is an ineffective procedure, the personnel must be distributed evenly in different work areas.The summary of tasks of a maintenance program affects such situations as man-hours, the performance of maintenance, the availability of equipment, and in some cases the organized structure of maintenance.

General description of the installation.-

• Name of the facility, giving a brief description of the activity Future growth plans, indicating the estimated date of completion Date of start of operations (only for facilities in operation) Estimated date of start of project operations Location of the facility or project. Street, city, town, municipality, department, postal code, telephone (s) and fax, or other reference Geographical coordinates of the facility or project Include scale location plans, describing and indicating the boundaries of the facility or project and land uses within a radius of 500 meters in its environment, as well as the location of vulnerable areas, such as: human settlements, protected natural areas, ecological reserve areas, bodies of water, etc.;clearly indicating the distances between them. Total area of ​​the facility or project and area required for the development of the activity. Description of accesses (sea, land and / or air): Necessary infrastructure. In the case of extensions, you must indicate in list form the current and projected infrastructure Related activities (industrial, commercial and / or services) that are linked to the activities that are developed or intend to develop Number of personnel in the operation installation.Related activities (industrial, commercial and / or services) that are linked to the activities that are developed or intend to develop Number of personnel in the operation of the facility.Related activities (industrial, commercial and / or services) that are linked to the activities that are developed or intend to develop Number of personnel in the operation of the facility.

Process description.-

• Mention the design criteria of the installation or project based on the characteristics of the site and the susceptibility of the area or natural phenomena and adverse meteorological effects. Detailed description of the process by production lines, main and secondary reactions involving materials considered of high risk (having to attach block diagrams) List all raw materials, products and by-products handled in the process, indicating those that are in the Highly Hazardous Activities Lists, specifying substance, maximum amount of storage in kg, flow in m ³/ hr, concentration, maximum production capacity, type of storage and safety equipment Type of containers and / or storage containers. Specify: characteristics, code or construction standards, dimensions, quantity or maximum storage volume per container, indicating the substance contained, as well as the safety devices installed in them Describe process and auxiliary equipment, specifying characteristics, estimated time of use and location. Also, attach a scale plan of the general arrangement of the facility or project.

Example:

Equipment	Equipment nomenclature	Features and capacity	specs	Service life (indicated by the manufacturer)	Estimated time of use	Location within the general arrangement of the plant
Bomb	P-1	Centrifuge Hydraulic seal 150 HP	460 Volts 3 phase 60 Herz Stainless steel 1400 lt / min	10 years	3 years	Drainage area

• Operating conditions. Attach the flow charts, indicating the following information:

1. Material balance Design and operating temperatures and pressures Physical state of the various process streams Characteristics of the facility's operating regime (continuous or batch) Diagrams of piping and instrumentation based on detailed engineering and corresponding symbology.

Workgroup.-

Nature.-

The working group is established and should include a person from the maintenance and operation function and a specialist RCM facilitator. The RCM project group defines and classifies the objectives and scope of the analysis, requirements and acceptance criteria policies with respect to safety and protection of the environment. As summarized below.

The work team must be highly proactive multidisciplinary, made up of people from the maintenance, operations and specialist departments. These people should be highly familiar with the subjects that concern them.

The group will be led by a facilitator who may or may not come from the departments named above. Performance improvement involves contributions in attitudes, organization, knowledge, cultural patterns, and results.

Functions of the working group.-

The functions of the working group are framed in carrying out continuous improvement activities in the operations of the company. These can be grouped into two work fronts.

• Reactive activities: Root Cause Analysis (ACR), problem solving Preactive activities: Reliability Centered Maintenance (RCM). With functional analysis and criticality analysis of equipment. Previous activities.

These analyzes allow us to know the order of implementation of the techniques to be used, in order to guarantee a significant impact on the systems studied.

Tasks to do.-

• Prepare the working group. Select profile personnel according to the nature of the project. Select natural replacements for each member of the group, the best way to achieve this is to have redundancy, that is to say, two operators (for example), one or both of them being able to be in each meeting, ensuring between them always being informed of the progress of the activities. Having replacements that work only in case of emergency, has associated various problems of a practical nature Prepare an inventory of systems to analyze or opportunities for improvement Carry out functional and criticality analysis or analysis of opportunities for improvement Prepare an implementation order of the RCM, estimating the positive impact for the company that could represent an improvement in them.Select the system or problem with the greatest possible impact and the highest probability of success Clearly define the functions of the systems or the nature of the problems Establish a precise and clear mission in consensus, define the objectives of the working group Prepare the schedules of activities, the nature of said schedule will depend on the work group, its needs and limitations, and may be from a weekly meeting, to daily meetings, five-year meetings or continuous work days (by weeks or project). until the implementation of activities and their follow-up Carry out a contingency plan to avoid any delay due to foreseeable problems, such as permits, vacations of any member of the group, Reach consensus with the plant management on the above points.Begin the analysis, starting with a simple but concise documentation of the previous steps Complete the analysis Suggest solutions Evaluate the economic feasibility of the solutions, remember that many possible solutions are not economically feasible Document the entire process above, making small summaries to present to the management Present the results to the plant management, the results must be with a complete economic judgment that supports its implementation Make the suggestions proposed and justified by the work team come true. follow-up on activities and their results, take measures if required, remember that it is about continuous improvement and not about improvement by jumping to the highest level of performance.Verify if the activities are applicable in other areas of the organization and implement them if necessary.

From the facilitator.-

The facilitator is the leader of the work team, he must facilitate the implementation of the philosophies or techniques to be used, taking advantage of the different skills of the personnel that make up the work team, the facilitator must be absolutely competent in the following areas:

1. Techniques to implement Analysis management Meeting management Time management Administration, logistics and bottom-up management Typical facilitator functions include:

• Organize and direct all the activities inherent to the project Planning, scheduling and conducting meetings. Guarantee the execution of meetings in any case, therefore it should manage alternatives to solve any inconvenience with the team members Select the level of analysis, define borders and scope, in addition to estimating the impact, duration and resources required for the Ensure that each deadline is fully understood before its execution Ensure the correct order of implementation, avoiding methodological leaps that affect the integrity of the process Ensure that the project is carried out within the schedule with an acceptable margin of error Coordinate all the support material for the team's work (plans, diagrams, etc.), as well as,keep all project documentation up to date (files, progress, etc.) and share it online with the group. Be the group's communications focal point by centralizing information related to the work topic. Keeping management informed about all plans and the progress of activities, it must generate constant high-quality reports. Be the technical voice that clarifies any (methodological) doubts presented by team members during any stage of the process. Of the cases, he should act as the transcriber of the information generated. Investigate deeply about the topics discussed and not settle for superficial information, having in many cases dedicate himself to corroborating the information generated in the meetings.Therefore, you must have sufficient judgment to know when the participation of a specialist is required. You must ensure that the solutions provided by the work team exceed the level of technical report, that is, they are actually implemented. Recognize training needs (technical or methodological) of group members and provide it when required and at their level Ensure consensus of the decisions made Motivate the group Manage problems: personal clashes, interruptions, etc.Be able to recognize training needs (technical or methodological) of group members and provide it when required and at their level Ensure consensus of the decisions made Motivate the group Manage problems: personal clashes, interruptions, etc.Be able to recognize training needs (technical or methodological) of group members and provide it when required and at their level Ensure consensus of the decisions made Motivate the group Manage problems: personal clashes, interruptions, etc.

Of the meetings.-

• It must be guaranteed that the work team has common objectives and knows (“roughly”) the methodology and the action plan. Take special care with occasional guests (give them enough information). They will be scheduled with work sessions of no more than 90 minutes, with 15-minute rest periods between sessions (if work days of more than 90 minutes are scheduled). Ideal session 50 minutes work + 10 minutes break (refreshment) Remember that meetings are social events and every effort should be made to make them enjoyable (these projects sometimes last for years) The meeting should be confirmed by the focal point in the plant, who should ensure the participation of the group and locate alternates if required. If it is not possible to bring together the entire multidisciplinary team,Work sessions can be held by specialty, guaranteeing the participation of a member of operations in each meeting The facilitator will prepare an agenda with objectives to be met in the meeting and they must be verified at the end of the meeting The results of the previous meeting must Make yourself known at the current meeting. Never suspend a meeting without setting the date and time of the next meeting by consensus. The atmosphere of the meeting should be blameless. “The search for solutions should not be a search for culprits destined for the stake.” The opinions of the members should not be negatively questioned. Internal problems should be solved by the group and stay with them. The objectives of the analysis and the process diagram should always be visible in the meeting room.The facilitator should encourage the participation of all members in an enthusiastic way. Meeting time should be used in an intelligent and efficient way. The existence of all the resources to be used in each meeting (manuals, plans, refreshments, etc.) They must be carried out in comfortable and accessible places for all the members. Analysis techniques can be used, such as brainstorming, fishbone diagrams, etc. Key information must be validated before continuing to work based on it. Work around realities and not opinions. Seek solutions to problems and not problems to solutions. Failure to comply with activities assigned to team members for the next meeting, results in serious setbacks.The facilitator and the focal point must guarantee the means for the team members to carry out these activities.

So in all this trance, communications play an important role, being channeled by the facilitator and the focal point, they should be in a vertical (up / down) and horizontal direction.

Main tasks of the RCM analysis.-

The main elements of the RCM analysis are summarized in twelve steps as follows:

• Studies and preparation Definition and selection of systems Functional analysis of failure Selection of critical items Treatment of non-critical items Collection and analysis of data Analysis of failure modes and their effects Selection of maintenance tasks Maintenance Determination of maintenance intervals Analysis and comparison of maintenance strategies Implementation of recommendations Follow-up of results

Study and preparation.-

Clearly define the objectives to be pursued with the analysis to be carried out, since their definition will determine the scope of the study. The systems to be evaluated are selected and the project monogram is established, identifying the necessary resources.

Definition and selection of systems.-

After the definition for the execution of the RCM analysis in the plant, two questions are considered:

• For which of the systems is the analysis beneficial, compared to traditional planning? At what level of installation (plant, system, subsystems, etc.) should the execution of the RCM be conducted?

The description of the hierarchical process installation (records, flowcharts) is a good tool for the system.

Functional analysis of the failure.-

After completing the previous step, the next step is to define and identify the functions of the teams and components of the teams under study. For the system selected in the previous subtitle under analysis, the following aspects should be considered:

1. Identify and describe the functions of the systems and the performance criteria Describe the operating requirements of the system Identify the ways in which the functions of the selected equipment may fail.

The application of Failure Modes and Effect Analysis is recommended for this analysis.

Selection of critical items.-

The fundamental objective of this task is to identify the components that are considered critical for the proper functioning of the system in question. The classification of a component as critical will imply the requirement of establishing some efficient preventive or predictive maintenance task that allows preventing its possible causes of failure.

To determine the criticality of an equipment failure, two aspects must be considered: its probability of occurrence and its severity. The probability of occurrence measures the estimated frequency of occurrence of the failure considered, while the severity measures the severity of the impact that this failure can cause on the installation.

If a reliable and efficient database is not available to calculate the aforementioned probabilities, its impact on the function or functions defined for the system under analysis can be considered as the only criterion to classify the criticality of equipment failures., although it is convenient to establish the appropriate measures so that, in the future, information related to the probability term may be available. In some cases, it may be appropriate to subdivide the system under evaluation into several clearly delimited subsystems to facilitate analysis. These subsystems, which are analyzed as if they were main systems, are characterized by developing a specific function in the system under consideration and are made up of certain components or equipment.

The interfaces of the system in question will constitute its borders with other systems of the plant and inside them are, normally, all the components whose criticality is going to be analyzed. In the technical procedures of the RCM project, a list of component types is usually established that are generally excluded from the analysis (for example: manual valves smaller than two inches, rigid supports, thermocouples, etc.).

Criticality analysis is, in essence, a reliability analysis of the considered system and usually consumes a significant level of resources. The classic method of evaluating the criticality of the components of a system consists in determining, first of all, the functions that the system in question must perform within the entire installation, as well as its associated functional failures. For each of these functional failures, those components whose failure leads to the functional failure under study are identified, causing negative effects on the installation. These components are called "critical components". This evaluation is normally carried out using the known reliability technique called "Failure Modes and Effects Analysis" (FMEA).

For certain systems, the optimization of the resources dedicated to the analysis of the criticality of their components is usually considered, reducing the systematic level of the analysis process that the development of an FMEA implies and the considerable volume of documentation that is generated. In such cases, a simplified method of analysis is usually used, being the "Criticality List" one of the most used. This method, based on the identification of the negative consequences that the potential failures of the different components may produce on the system under study, consists of applying a list or battery of questions to each component of the considered system, based on their answers., catalog it as critical or non-critical. These questions have to do, among other aspects, with the loss of production, security,of the suitable conditions of operation or the increase of environmental contamination.

Treatment of non-critical items.-

In the previous step the critical items are selected for the extensive analysis of the RCM. But it happens that there are items in the system that are not analyzed, in this case the plants have a maintenance program for these non-critical items, or they carry out maintenance according to the supplier's technical specifications.

Although RCM theory admits that components considered non-critical are allowed to operate to failure without applying any preventive maintenance, an evaluation of these non-critical components is recommended before making this decision.

Data collection and analysis.-

The data necessary for the RCM analysis can be categorized into the following three groups:

• Design data Operational data Reliability data

For data analysis, statistical techniques and probability are applied, with the appropriate adjustment to a probability distribution law, which provide a graphical solution to the analysis of the plotted curves; the type of analysis that relates the possible failure modes that can be extended with the revision of the previous curves.

Analysis of Failure Modes and their Effects.-

The objective of this step is to identify the dominant failure modes, as described above using different failure identification methods.

Selection of maintenance tasks.-

The result of the critical items selection task is the list of components (selected critical and non-critical) to which it will be convenient to identify an efficient preventive or predictive maintenance task. The objective of the present task is to carry out said assignment of maintenance activities. In a generic way, the process of selecting maintenance tasks begins with the identification of the most probable causes associated with the different failure modes of the components considered.

The application of a Logical Decision Tree (ALD, Figure 1) is a systematic and homogeneous process for selecting the most appropriate maintenance strategy to prevent the cause that causes the appearance of a certain failure mode corresponding to a system component. object of analysis. For the construction of this AML, the criteria to be considered and their corresponding priorities must be previously defined. Thus, for example, priority may be given to the prevention of the failure over its correction, to the application of maintenance techniques based on the operating condition of the equipment compared to periodic maintenance activities or to consider aspects such as the evidence of failures for the operators when such failures occur.

The result of this task will be the set of recommended maintenance activities for each piece of equipment. The specific content of the specific activities to be carried out and their corresponding execution frequencies will be defined. In this regard, it may be useful to develop "templates" in which the available knowledge on the maintenance of the different types of equipment is collected, in order to establish the appropriate tasks and frequencies of execution in a systematic and homogeneous way, depending on aspects such as the criticality of the equipment, its frequency of use or the specific environmental conditions of its operating environment, among others.

Determination of maintenance intervals.-

To determine the optimal maintenance intervals, information about the failures, i.e. the failure ratio function, the consequences and costs of failures, etc., is necessary.

Analysis and comparison of maintenance strategies.-

The criteria for the selection of maintenance tasks used in the RCM have two requirements:

• Applicability Effectiveness

Applicability: a maintenance program is applicable, when it can eliminate the failure, or reduce the probability of occurrence to an acceptable level, reducing the impact of failures.

Effectiveness: means that the cost of maintenance tasks is less than the costs of failures. The defined maintenance schedule tasks.

Implementation of recommendations.-

Once the maintenance activities considered most efficient for the different components analyzed have been selected, the final recommendations of the RCM study are established and their implementation is carried out. First, the current maintenance tasks in the installation are compared with the recommendations of the RCM analysis. The result of this activity is the final set of maintenance tasks that you propose to apply to each component. Said final maintenance tasks will have arisen from applying the following criteria:

• If a current maintenance task in the plant has not been recommended by the RCM study, it will be proposed to be canceled. If a maintenance task recommended by the RCM study is not currently being applied, it will be proposed to incorporate it into the maintenance plan. If a current maintenance task in the plant coincides with a task recommended by the RCM study, its retention will be proposed If the frequency of a current maintenance task in the plant does not coincide with that of a task recommended by the RCM study with the same content, its modification will be proposed.

Based on these final recommendations, the new maintenance plan proposed for the installation must be drafted. For this, the approval of the proposed recommendations by management is essential, who will also set the application criteria and assign the necessary resources.

The development of the new maintenance plan, in addition to the technical bases of maintenance obtained with the RCM analysis, will require considering other aspects such as existing commitments, unrelated to maintenance, that imply the performance of certain tasks and the degree of efficiency achieved. in the grouping of different maintenance activities. In some cases, it will be necessary to develop new work procedures and make adaptations of existing computer processes that may be related to the subject.

Results monitoring.-

The monitoring and analysis of the results that are obtained in the plant with the implementation of the new maintenance program are tasks that are of paramount importance for the evaluation of its effectiveness. This process will require, on the one hand, the definition of the monitoring parameters and indices, the implementation of the relevant processes for capturing the necessary basic information, the establishment of the appropriate action procedure and the corresponding allocation of resources.

The need to consider new maintenance techniques, add a possible failure mode or component not initially analyzed or review the study hypotheses, its conclusions, among others, will make it convenient to update the global study of the RCM, from time to time in order to minimize the obsolescence of the recommendations provided over time.

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