**2.2 Fundamental aspects in the maintenance strategies**

Maintenance decisions are of diverse natures and, depending on the level of impact, require proper identification and ranking. This is the starting point to develop suitable management policies and bring assertive strategies of reliability. Decisions associated with production maintenance are of four levels:


*Reliability and Maintenance - An Overview of Cases*

function check-out, or combinations" [19].

order to sustain or extend its useful life."

physical or performance variable [24].

a.Equipment has a life cycle

the organization and/or its stakeholders

is operated until it fails.

eventually die" [25].

for engineers

such as equipment

**2.1 Concepts and definitions**

The Federation of European Risk Management Associations (FERMA) states that it would be practically impossible to encompass every technique for risk analysis in a single standard and, likewise, impossible to resolve all problems with only one method. For this reason, each industry must adapt or develop its own method instead of trying to find a single general method. In other words, the methods implemented must consider the actual operation and asset failure, as well as the operating environments thus far, since all these aspects affect its performance.

The British Standard Glossary defined maintenance as "the combination of all technical and administrative actions, including supervision actions, intended to retain an item in, or restore it to, a state in which it can perform a required function" [18]. In addition, maintenance is a set of organized activities that are carried out in order to keep an item in its best operational condition with minimum cost required. Likewise, maintenance tasks are defined as "Sequence of elementary maintenance activities carried out for a given purpose. Examples include diagnosis, localization,

Preventive maintenance is the performance of inspection and/or servicing tasks that have been pre-planned or scheduled for specific points in time in order to retain the functional capabilities of operating equipment or systems [20, 21]. Other standards such as ISO 13372:2012 [22] define preventive maintenance as "maintenance performed according to a fixed schedule, or according to a prescribed criterion, that detects or prevents degradation of a functional structure, system or component, in

Corrective or reactive maintenance is carried out after fault recognition and intended to put an item into a state in which it can perform a required function [23]. This maintenance policy is also called failure-based maintenance because the asset

Robert Davis defined asset management as "a mindset which sees physical assets not as inanimate and unchanging lumps of metal/plastic/concrete, but as objects and systems which respond to their environment, change and normally deteriorate with use, and progressively grow old, then fail, stop working, and

**Table 1** shows additional important concepts of maintenance management for

b.Maintenance management is as important for those working in finance as it is

c.It is an approach that looks to get the best out of the equipment for the benefit of

d.It is about understanding and managing the risk associated with owning assets

reliability systems, in which the following four factors are recognized:

Predictive maintenance refers to the routine inspection of equipment, machines, or materials to prevent a failure. It is a type of proactive maintenance that focuses on determining the potential root causes of machine or material failure and dealing with those issues before problems occur. It is achieved by the measurement of some

**6**


The strategic level incorporates the top direction of the organization and the maintenance implementation with tangible results in a time frame upward of 2 years. These decisions require important investments of resources and market studies, opportunities, and returns on investment.

In operations and production, tactical decisions generate results within several months to 1 or 2 years. Tactical decisions are made by management and mid-level management, involve project modifications, and often are associated with important investments. Operation-specific decisions have immediate impact (from several days to a few months) and are made by technical personnel that do not require changes and investments in the operational budgets. Instrumental or dispatch decisions are also made by technical personnel. The costs related to these decisions are considered in the plans pertaining to preventive maintenance, and their impact is reflected in hours. The maintenance activities related to these decisions are called adjustments.

Often, the governing bodies of the industries only stop to consider the need to restructure their departments or maintenance processes when faced with frequent expensive failures or costly downtimes that cause significant production losses. In addition to the above, performed research indicates that implied processes of documentation and registration processes are precarious, even though, in many cases, significant sums of money have been invested in information systems. When


#### **Table 1.**

*Concepts for maintenance management for reliability systems [26].*

confronted with these loss-potential scenario initiatives to strengthen and structure, the corresponding maintenance departments are taken.

The following are the first steps to properly establish the maintenance requirements inside the organization to guarantee high reliability, equipment availability, and compliance with operational and environmental risk regulations.

It has to be noted however that discussing the performance evaluation of a production system without having prior implemented a maintenance information system may lead to inherent failures. Indeed, an MIS is a tool in which failures, time interventions, spare parts, etc. are saved, treated, and processed in order to inform maintenance managers and facilitate decisions. Although there could be other tools to evaluate the performance of the production equipment, the maintenance information system is where the key indices are considered and integrated with the general maintenance strategies.

Overall, a maintenance information system has four main functions:

a.Collect data

b.Support engineering decisions

c.Record interventions

d.Plan for spare parts and equipment expenses [27, 28].

The MIS can be integrated with a general computerized maintenance management system (CMMS).

The following sections introduce on the one hand its basic aspects and on the other hand highlight the means of using one for performance evaluations and, subsequently, decision-making processes.

In order to have organized and conscientious data collection, it is imperative to define the following:

a.The critical assets

b.The failure

c.The desired capabilities and limits according to the functions for which the assets were designed

**9**

equipment.

**3. Result and analysis**

**3.1 Proposed maintenance strategy model**

motivation among personnel [36].

*Maintenance and Asset Life Cycle for Reliability Systems DOI: http://dx.doi.org/10.5772/intechopen.85845*

and detailed descriptions of activities and operative windows.

Once static data is collected, it is important to record information related to failures and interventions. It is at this point where the record of work orders and failure report may be used as it may be regarded as the foundation of the availability and maintenance indicators incorporating essential information concerning financial planning and evaluation. The correct filing of work orders should include at least the nametag of the asset, time records, workforce, downtimes, spare parts,

Similarly, a fault report should accurately describe the type, nature, and time the fault was observed and, if it is already cataloged, put the fail mode number or tag. There are international standards such as the ISO 14224 describing general guidelines to report faults and tag them. One of the biggest benefits of recording the failures according to the international standard is the ability to share and use information to estimate failure rates. An example of the failure rate prediction and database is in the OREDA Handbook for the offshore oil and

A work order is the main tool that allows recording fault information. It begins with a planning process in which the workforce, deadlines, procedures, and route sheets are established. The work order continues with a programming stage where the precise dates and the maintainer's ID are selected, and, after this, the work order is executed and closed in the information system. This last step may be regarded as the triggering point and the interface to the real world as it gives rise to all these processes, since it documents and depicts in the equivalent data record, the KPI's

Even so, work orders and failure reports are not enough. If only work order data is tracked, it is difficult to establish tendencies, averages, and alerts. As such, it may not be possible to establish equipment-specific degradation levels as well [34]. This is when quantitative variables become necessary because they indicate the performance state of the equipment. These quantitative variables come from sensory devices such as gauges, thermometers, pressure and temperature transducers, flow meters, gas detectors, vibration sensors, etc. It is important to highlight the fact that a quantitative variable could be useful only if the correct functions of the equipment and their parameters are well established. This may be demonstrated by using the PF curve [35]. In some plants, SCADA and DCS are commonly found where the variables can be analyzed remotely and stored, and, in many cases, they are only used for operational purposes. In brief, quantitative and qualitative maintenance and cost data are necessary to evaluate the performance of any asset or piece of

The model proposed strategically incorporates the "better practices of maintenance management" in order to achieve operational excellence in the framework of the international standard ISO 55000:2014. Better practices in maintenance management have the following attributes: they are realistic, specific, achievable, and tested in the industry; they contribute in making maintenance more efficient and profitable, while optimizing operation costs and improving equipment's reliability. Authors have equally postulated an overall improved level of satisfaction and

computing, evaluation, and the provision for making decision [31–33].

• Catalogs, technical bulletins, etc.

gas industry [29, 30].

The reason therein may be associated but not limited to the fact that the plant could have hundreds of assets which could result in useless, inefficient work. Data collection should begin with an organized set of information which must include static information, such as:


• Catalogs, technical bulletins, etc.

*Reliability and Maintenance - An Overview of Cases*

regulations.

general maintenance strategies.

c.Record interventions

ment system (CMMS).

define the following:

b.The failure

a.The critical assets

assets were designed

static information, such as:

• Hierarchy classification

• Nameplate information

• Functional analysis charts

• Assembly and spare part drawings

• Processes and instrumentation diagrams (PIDs)

b.Support engineering decisions

subsequently, decision-making processes.

a.Collect data

confronted with these loss-potential scenario initiatives to strengthen and struc-

The following are the first steps to properly establish the maintenance requirements inside the organization to guarantee high reliability, equipment availability, and compliance with operational and environmental risk

It has to be noted however that discussing the performance evaluation of a production system without having prior implemented a maintenance information system may lead to inherent failures. Indeed, an MIS is a tool in which failures, time interventions, spare parts, etc. are saved, treated, and processed in order to inform maintenance managers and facilitate decisions. Although there could be other tools to evaluate the performance of the production equipment, the maintenance information system is where the key indices are considered and integrated with the

Overall, a maintenance information system has four main functions:

The MIS can be integrated with a general computerized maintenance manage-

The following sections introduce on the one hand its basic aspects and on the other hand highlight the means of using one for performance evaluations and,

In order to have organized and conscientious data collection, it is imperative to

c.The desired capabilities and limits according to the functions for which the

The reason therein may be associated but not limited to the fact that the plant could have hundreds of assets which could result in useless, inefficient work. Data collection should begin with an organized set of information which must include

d.Plan for spare parts and equipment expenses [27, 28].

ture, the corresponding maintenance departments are taken.

**8**

Once static data is collected, it is important to record information related to failures and interventions. It is at this point where the record of work orders and failure report may be used as it may be regarded as the foundation of the availability and maintenance indicators incorporating essential information concerning financial planning and evaluation. The correct filing of work orders should include at least the nametag of the asset, time records, workforce, downtimes, spare parts, and detailed descriptions of activities and operative windows.

Similarly, a fault report should accurately describe the type, nature, and time the fault was observed and, if it is already cataloged, put the fail mode number or tag. There are international standards such as the ISO 14224 describing general guidelines to report faults and tag them. One of the biggest benefits of recording the failures according to the international standard is the ability to share and use information to estimate failure rates. An example of the failure rate prediction and database is in the OREDA Handbook for the offshore oil and gas industry [29, 30].

A work order is the main tool that allows recording fault information. It begins with a planning process in which the workforce, deadlines, procedures, and route sheets are established. The work order continues with a programming stage where the precise dates and the maintainer's ID are selected, and, after this, the work order is executed and closed in the information system. This last step may be regarded as the triggering point and the interface to the real world as it gives rise to all these processes, since it documents and depicts in the equivalent data record, the KPI's computing, evaluation, and the provision for making decision [31–33].

Even so, work orders and failure reports are not enough. If only work order data is tracked, it is difficult to establish tendencies, averages, and alerts. As such, it may not be possible to establish equipment-specific degradation levels as well [34]. This is when quantitative variables become necessary because they indicate the performance state of the equipment. These quantitative variables come from sensory devices such as gauges, thermometers, pressure and temperature transducers, flow meters, gas detectors, vibration sensors, etc. It is important to highlight the fact that a quantitative variable could be useful only if the correct functions of the equipment and their parameters are well established. This may be demonstrated by using the PF curve [35]. In some plants, SCADA and DCS are commonly found where the variables can be analyzed remotely and stored, and, in many cases, they are only used for operational purposes. In brief, quantitative and qualitative maintenance and cost data are necessary to evaluate the performance of any asset or piece of equipment.
