Understanding Maintenance

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Goals of this section are to understand:

• Why do maintenance?

• The objective of maintenance

• Benefits of maintenance

• Types of maintenance approaches

• Purpose of CMMS/EAM

• Maintenance quality challenges

• Importance of assessing your maintenance program regularly

1 Introduction

What Is Maintenance and Why Is It Important?

Maintenance is concerned with keeping an asset in good working condition so that the asset may be used to its full productive capacity. The maintenance function includes both upkeep and repairs. The dictionary defines maintenance as "the work of keeping something in proper condition" A broader definition is:

• Keep in 'designed' or an acceptable condition;

• Keep from losing partial or full functional capabilities;

• Preserve, protect.

This definition implies that the term maintenance includes tasks per formed to prevent failures and tasks performed to restore the asset to its original condition.

However, the new paradigm of maintenance is related to capacity assurance. With proper maintenance, the capacity of an asset can be realized at the designed level. For example, the designed capacity of production equipment of x units per hour could be realized only if the equipment is operated without considerable downtime for repairs.

An acceptable capacity level is a target capacity level set by management. This level cannot be any more than the designed capacity. Consider production equipment that is designed to make 500 units per hour at a maintenance cost of $200 per hour. If the equipment is down 10% of the time at this level of maintenance, the production level will be reduced to 450 units per hour. However, if the maintenance department, working with the production department together as a team, can find a way to reduce the downtime from 10% to 5% at a slightly increased maintenance cost/hour, this reduction will increase the output by another 25 units/hour.

Therefore, it’s conceivable that management would be able to justify the increased maintenance cost. Thus capacity could be increased closer to designed capacity by reducing downtime.

Unfortunately, literature related to maintenance practices over the past few decades indicates that most companies did not commit the necessary resources to maintain assets in proper working order. Rather, assets were allowed to fail; then whatever resources needed were committed to repair or replace the failed asset or components. In fact, maintenance function was viewed as the necessary evil and did not receive the attention it deserved.

However, in the last few years, this practice has changed dramatically. The corporate world has begun recognizing the reality that maintenance does add value. It’s very encouraging to see that maintenance is moving from so-called "backroom" operations to the corporate board room. A case in point -in the 2006 annual report to investment brokers on the Wall Street, the CEO of Eastman Chemical included a couple of slides in his presentation related to maintenance and reliability stressing the company's strategy of increasing equipment availability by commit ting adequate resources for maintenance.

2 Key Terms and Definitions


An asset is defined as something that has potential or actual value to an organization; the physical resources of an organization, such as equipment, machines, mobile fleet, systems, or their parts and components, including software that performs a specific function or provide a service; sometimes also referred to as physical assets.


An item or subassembly of an asset, usually modular and replace able, sometimes serialized depending on the criticality of its application; interchangeable with other standard components such as belt of a conveyor, motor of a pump unit, or a bearing.

Computerized Maintenance Management System / Enterprise Asset Management (CMMS / EAM)

A software system that keeps record and tracks all maintenances activities, e.g., maintenance work orders, PM schedules, PM masters, material parts, work plans, and asset history. Usually it’s integrated with support systems such as inventory control, purchasing, accounting, manufacturing, and controls maintenance and warehouse activities.

Failure Mode and Effects Analysis (FMEA)

A technique to examine an asset, process, or design to determine potential ways it can fail and the potential effects(consequences); and subsequently identify appropriate mitigation tasks for highest priority risks.

Maintenance, Backlog

Maintenance tasks those are essential to repair or prevent equipment failures that have not been completed yet.

Maintenance, Capital Project (CPM)

Major repairs, e.g., overhauls and turnaround projects, valued over a certain threshold are sometime treated as capital projects for tax purposes. If these projects are essential to restoring the asset back to the designed capacity - not to add additional capabilities, they should be treated as maintenance costs.

Maintenance, Condition Based (CBM)

Maintenance based on the actual condition (health) of an asset as determined from non-invasive measurements and tests. CBM allows preventive and corrective actions to be optimized by avoiding traditional calendar or run-time directed maintenance tasks. The terms Condition Based Maintenance (CBM), and Predictive Maintenance (PdM) are used interchangeably

Maintenance, Corrective (CM)

Repair actions initiated as a result of observed or measured conditions of an asset after or before the functional failure.

Maintenance, Operator Based (OBM)

OBM involves operators performing some basic maintenance activities. Operator-based maintenance is a cost-effective practice to perform minor routine, and recurring maintenance tasks by the operators to keep the asset working efficiently for its intended purpose.

Maintenance, Predictive (PdM)

A maintenance strategy based on the actual condition (health) of an asset as determined from non-invasive measurements and tests. PdM allows preventive and corrective actions to be optimized by avoiding traditional calendar or run-time directed maintenance tasks. The condition of equipment could be measured using condition monitoring, statistical process control, or equipment performance, or through the use of the human senses. The terms Predictive Maintenance (PdM) and Condition Based Maintenance (CBM) are used interchangeably

Maintenance, Preventive (PM)

A maintenance strategy based on inspection, component replacement, and overhauling at a fixed interval, regardless of its condition at the time. Usually, scheduled inspections are performed to assess the condition of an asset. Replacing service items, e.g., filters; oils, and belts and lubricating parts are a few examples of PM tasks. PM inspection may require another work order to repair other discrepancies found during the PM.

Maintenance, Reactive (RM)

Maintenance repair work done as an immediate response to an asset failure, normally without planning and unscheduled.

Synonymous with breakdown and emergency maintenance.

Maintenance, Run-to-Failure (RTF)

A maintenance strategy (policy) for assets where the cost and impact of failure is less than the cost of preventive actions. It’s a deliberate decision, based on economical effectiveness, not to perform PM but let asset run to fail.

Proactive (Maintenance)Work

The sum of all maintenance work that is completed to avoid failures or to identify defects that could lead to failures (failure finding). It includes routine preventive and predictive maintenance activities and work tasks identified from them.


The probability that an asset or item will perform its intended functions for a specific period of time under stated conditions.

Reliability Centered Maintenance (RCM)

A systematic, disciplined process, for establishing the appropriate maintenance plan for an asset/system to minimize the probability of failures. The process ensures safety, system function, and mission compliance.

3 Maintenance Approaches

Many organizations have many different approaches (or some may call practices) when it comes to their maintenance programs. All approaches have at their basis the requirement to keep their facility's assets at whatever capacity level is necessary for their current operational needs. Some of these maintenance programs are more structured than others-some maintenance programs are based on an RCM analysis, and some organizations even develop an annual or even multi-year maintenance program plan to guide their maintenance decisions strategically and tactically. The truth is that an organization will have a maintenance pro gram whether they admit it or not; their program will simply be more costly than it has to be since they will live in a reactive maintenance state. All assets requires some form of care-maintenance, for example.

Belts and chains require adjustment, alignment of shafts such as pump motor or blower-motor shafts need to be properly maintained, filters need to be changed at regular intervals, proper lubrication on rotating machinery is required, and so on. In some cases, certain components need replacement after a specified number of hours of operations, e.g., a pump bearing on a hydraulic system to ensure that the system lasts through its design life. Anytime we fail to perform maintenance activities, we may be shortening the operating life of the asset. Over the past few decades, many cost-effective approaches have been developed to insure an asset reaches or exceeds its design life. Instead of waiting for assets to fail and then fix them, maintenance actions are performed to keep assets in good working condition to provide continuous service.

Why Have a Structured Maintenance Program

The most important reason to have a maintenance program with a structured approach is to ensure that assets don't fail prematurely, that they keep producing or providing service as intended. Maintenance pro grams should improve production capacity and reduce overall facility costs by:

• Reducing production downtime - the result of fewer asset failures.

• Increasing life expectancy of assets, thereby eliminating premature replacement of machinery and asset.

• Reducing overtime costs and providing more economical use of maintenance personnel due to working on a scheduled basis, instead of an unscheduled basis, to repair failures.

• Reducing cost of repairs by reducing secondary failures. When parts fail in service, they usually damage other parts.

• Reducing product rejects, rework, and scrap due to better overall asset condition.

• Identifying assets with excessive maintenance costs, indicating the need for corrective maintenance, operator training, or replacement of obsolete assets.

• Improving safety and quality conditions.

A structured maintenance program can have different philosophies, approaches, and practices embedded within the program. The basic philosophy is really only two-fold: do some form of maintenance to an asset to prevent failure or allow the asset to be run-to-failure. The basic approaches to maintenance can be grouped into four major categories:

Condition Based Maintenance (also known as Predictive Maintenance), Preventive Maintenance, Proactive Maintenance, and Corrective Maintenance.

A brief description of each of these approaches is discussed on the following pages with more details on each covered within sections 4 and 8.

Condition Based Maintenance (CBM)

Condition Based Maintenance (CBM), also known as Predictive Maintenance (PdM), attempts to evaluate the condition of an asset by per forming periodic or continuous asset monitoring. The ultimate goal of CBM is to identify proactive maintenance actions to be performed at a scheduled point in time when the maintenance activity is most cost effective and before the asset fails in service. The "predictive" component stems from the goal of predicting the future trend of the asset's condition.

This approach uses principles of statistical process control, trend analysis, and preselected thresholds to determine at what point in the future maintenance activities should be scheduled.

CBM inspections typically are performed while the asset is operating, thereby minimizing disruption of normal system operations. Adoption of CBM/PdM in the maintenance of an asset can result in substantial cost savings and higher system reliability.

There are a number of different CBM / PdM technologies that can be used to evaluate assets condition. A few of the more common technologies (or data) are:

• Vibration analysis

• Infrared (IR) thermography

• Acoustic / Ultrasonic -- sound level measurements

• Oil analysis

• Electrical - amperage plus other data

• Shock Pulse Method (SPM)

• Partial discharge & Corona detection

• Operational performance data - pressure, temperature, flow rates, etc.

Basically, in the CBM approach, the maintenance need is based on the actual condition of the machine rather than on some preset schedule.

Activities such as changing oil are based on a predetermined schedule (time), like calendar time or asset runtime. For example, most of us change the oil in our cars every 3,000-5,000 miles driven. This is effectively basing the oil change needs on asset runtime. No concern is given to the actual condition and performance capability of the oil. It’s changed because it’s time to change it. This methodology would be analogous to a preventive maintenance task.

On the other hand, if we ignore the vehicle runtime and have the oil analyzed at some regular period to determine its actual condition and lubrication properties, then we may be able to extend the oil change until the car has been driven 10,000 miles, or maybe even more.

This is the advantage of utilizing condition based maintenance. CBM is used to define needed maintenance tasks based on quantified asset conditions or performance data. The advantages of CBM are many. A well established CBM program will eliminate or reduce asset failures cost effectively. It will also help to schedule maintenance activities to minimize overtime cost. In addition, we will be able to minimize inventory and order parts, as required, well ahead of time to support the downstream maintenance needs.

Past studies have shown that a well-implemented CBM program can provide an average savings of 10% (7-15%) over a program utilizing preventive maintenance (PM) alone. These savings could easily exceed 30-40% if there is not a good PM program in place. In fact, independent surveys and technical papers presented at the International Maintenance Conferences 1999-2002 combined with the author's own experience indicate the following industrial average savings resulting from a good established condition based maintenance program:

• Reduction in maintenance costs: 15-30%

• Reduction in downtime: 20-40%

• Increase in production: 15-25%

On the down side, starting a full-blown CBM program utilizing all of the previously mentioned technologies can be quite expensive. Some technology's test equipment may cost in excess of $40,000. In addition, training plant personnel to utilize PdM technologies effectively will require considerable funding as well. This is one reason to have an RCM basis for choosing where to apply which CBM technology; it helps to determine the test equipment purchase that can provide the most "bang for your buck." Program development will require an understanding of predictive maintenance and a firm commitment to make the program work by all facility organizations and management.

How the CBM team should be organized is another issue. We have found that a centralized dedicated team is a good way to start a program.

This approach helps in standardizing testing methods and practices.

The CBM approach consists of scheduling maintenance activities only when equipment or operational conditions warrant - by periodically or continuously monitoring the machinery for excessive vibration, temperature, noise, etc. When the condition gets to a level that has been pre determined to be unacceptable, the asset is shut down. The asset is then repaired or has damaged components replaced in order to prevent more costly failures from occurring. This approach works very well if personnel have adequate knowledge, skills, and time to perform the CBM work.

In addition, the company must allow asset repairs to be scheduled in an orderly manner. The approach provides some lead-time to purchase materials for the necessary repairs, reducing the need for a high parts inventory. Because maintenance work is only performed when it’s needed, there is likely to be an increase in production capacity.

Preventive Maintenance (PM)

As stated previously, a CBM approach is the preferred approach if your organization can handle the expense of implementing this approach.

However, a PM approach is the next best thing and maybe the only approach with certain types of assets. Additionally, regulatory requirements may force some level of PM to be performed (e.g., crane inspections).

Preventive Maintenance requires that maintenance or production/operation personnel pay regular visits to monitor the condition of an asset in a facility. The basic objective of PM visits is to take a look at the asset to determine if there are any telltale signs of failure or imminent failure. Also, depending on the type of the asset, a checklist or a procedure with task details indicating what to check or what data to take may be used, e.g., change filter, adjust drive belts, and take bearing clearance data. The observers also document the abnormalities and other findings.

These abnormalities should be corrected before they turn into failures for a PM program to add any value.

These PM inspections can be based on either calendar time or asset runtime. If CBM is not being performed on a particular piece of equipment, or if CBM cannot detect a particular failure, then the next best approach is a runtime-based PM program, but only for equipment and failure modes that have a time basis. If a calendar time-based PM program is all that really adds value, then that approach is still better than a run-to failure strategy. The exception to this is when an analysis has been per formed that indicates the most cost-effective strategy is run-to-failure because the total cost of maintenance is less than the corrective maintenance necessary for this run-to-failure strategy (assuming that there is no safety impact to this run-to-failure strategy).

The objective of preventive maintenance can be summarized as follows:

• Maintain assets and facilities in satisfactory operating condition by providing for systematic inspection, detection, and correction of incipient failures before they develop into major failure.

• Maintenance, including tests, measurements, adjustments, and parts replacement, performed specifically to prevent failure from occurring.

• Record asset health condition for analysis which leads to the development of corrective tasks.

Proactive Maintenance

Proactive Maintenance is one of those terms used to mean different things to different people. The term can be a controversial one. Some consider CBM and PM approaches to be proactive -these approaches do take a proactive approach as opposed to simply reacting to equipment failure. In some cases, tasks that are generated based on what is found during CBM and PM tasks (including work identified as a result of root cause and failure analysis) are considered proactive. In some organizations, proactive maintenance is calculated as a ratio of all maintenance work minus unscheduled corrective maintenance, divided by all maintenance work. Another definition is that anything on the maintenance schedule is proactive - that is, any maintenance work that has been identified in advance and is planned and scheduled. These last definitions make better sense. Therefore, proactive maintenance can be defined as all work tasks completed to avoid failures or to identify defects that could lead to failures.

Corrective Maintenance (CM)

Corrective Maintenance is another term used in different ways. CM is an action initiated as a result of an asset's observed or measured condition before or after functional failure. CM work can be further classified into Scheduled, Major Repairs/Projects, and Reactive.

When an asset breaks down, it fails to perform its intended function and disrupts scheduled operation. This functional loss, partial or total, may result in defective parts, speed reduction, reduced output, and unsafe conditions. For example, a wear or slight damage on a pump impeller, which reduces output, is a function reduction failure. Full functional failure that shuts down the asset is called function-disruption failure.

Function-disruption or reduction failures that are not given due attention will soon develop into asset stoppage if not acted on.

Many abnormalities such as cracks, deformations, slacks, leakages, corrosions, erosions, scratches, excessive heats, noises, and vibrations are the indicators of imminent troubles. Sometimes these abnormalities are neglected because of the insignificance or the perception that such abnormalities won’t contribute to any major breakdowns. The tendency to overlook such minor abnormalities soon may grow and contribute to serious catastrophic failures. It’s not uncommon to receive queries from production staff in response to a "high temperature or vibration condition" about how long we can continue running.

It has been observed that a high percentage of the failures occur during startups and shutdowns. However, asset failure could also be due to poor maintenance. Causes that go unnoticed are called "hidden abnormalities." The key to achieving zero failures is to uncover and rectify these hidden abnormalities before failure actually occurs.

In many organizations, CM is called repair maintenance; it’s conducted to correct deficiencies and to make the asset work again after it has failed or stopped working.

4 Other Maintenance Practices

In addition to maintenance approaches that are used to form a more structured maintenance program, maintenance practices are also used to define a company's program. One of the key maintenance practices used by companies to effectively execute their maintenance program is related to operator-based maintenance, including the use of operators in designing for maintenance and reliability.

Operator-Based Maintenance (OBM)

Unlike what is typically assumed, the operator is actually one of the most important members of the maintenance team. Well-informed, trained, and responsible operators will ensure that assets are being kept in good working order.

Operators are the first line of defense against unplanned asset down time. OBM assumes that the operators who are in daily contact with the assets can use their knowledge and skills to predict and prevent break downs and other losses.

The main objective of an Operator's Maintenance program (aka autonomous maintenance program) is to equip operators with the following asset-related skills:

• Ability to detect abnormalities

• Ability to correct minor abnormalities and restore function, if they can

• Ability to set optimal asset conditions

• Ability to maintain optimal equipment conditions

Autonomous maintenance is one of the basic pillars of Total Productive Maintenance (TPM). TPM is a Japanese maintenance philosophy which involves operators performing some basic maintenance activities. The operators learn the maintenance skills they need through a training program. They then perform the following tasks:

• Conduct general inspection.

• Keep assets clean and all areas accessible.

• Identify and eliminate problem sources.

• Support and create cleaning and lubricating standards and procedures.

• Standardize through visual workplace management.

• Implement autonomous asset management.

• Perform minor maintenance and service items, e.g., replacing filters, lubricating, and changing oil.

• Work with the maintenance team to repair what they are unable to perform.

The operators use the following four sensory tools to identify problem areas, then either fix them or get help to get the problems repaired before they turn into major failures.

a. Look for any abnormalities - clean, in place, accessible.

b. Listen for abnormal noises, vibrations, leaks.

c. Feel for abnormal hot or cold surfaces.

d. Smell abnormal burning or unusual odors.

The following suggested measures could help in achieving that goal:

a) Operator Involvement

Operators can detect any abnormalities and symptoms at an early stage and get them corrected before they turn into major failures. O&M personnel can ensure that all the assets are properly secured and bolted.

The support structures - piping, hoses, guards, etc. - are not loose and vibrating. These should be properly fastened.

b) Cleaning

Cleaning leads to inspection and timely detection of any incipient failures like cracks and damaged belts. Dirt and dust conceal small cracks and leaks. If an asset is clean, we could assess if things are not working right, e.g., leaking, rubbing, and bolt loosening, which may be an indication of an incipient failure.

Keep assets and the surrounding area clean. A clean asset creates a good feeling and improves employee safety and morale.

c) Lubricating

Lubrication helps to slow down wear and tear. Check if components are being lubricated properly with the correct type of lubricants and that oil is being changed at the proper frequencies. Don't over-lubricate; use the right amount. Ultrasonic guns can be used to ensure the required amount of lubricant is used. Apply 5S plus or 6S practices to have a lubrication plan, with pictures identifying all lube points and the type of lubricant to be used.

d) Operating Procedures

All operating procedures available at the site should be current. Are these procedures easily understood? Do operators know how to shut down or provide lockout / tag out for the asset safely in case of an emergency? Do they know what operating parameters - pressures, temperature, trip/alarm settings, etc., - to watch? Make sure that operators and other support personnel have a good understanding of the answers to these questions. It’s a good practice and very desirable to have these operating instructions laminated and attached to the asset.

e) Maintenance Procedures

Be sure that maintenance / repair procedures are current when used.

Maintenance personnel should have the right tools available to perform maintenance correctly and effectively. Having a current procedure is an ISO principle.

When an asset is ready to be repaired, all items identified in the work plan should be staged at the asset site for craft personnel to execute their work in the most effective and efficient manner. Specialized tools should be kept at or near the asset with proper markings.

It’s a good practice to laminate the procedures, drawings, part list, wiring diagrams, logic diagrams, etc., and make them available at or near each asset location.

f) Operating Conditions

All assets are designed to operate under specific conditions. Check that assets are operating in the correct environment and are not being mis used, i.e., overloaded or unsafely used. If they are not being operated in their designed environment, (e.g., they are being used at much higher level of speed than normal use), take steps to see that appropriate safety precautions are being taken and all concerned personnel are aware of the risks involved.

g) Workforce Skills

Ensure that the workforce, operators, maintainers, and support staff are all properly trained and have the right skill sets to operate and maintain the asset effectively. Although ignorance and lack of skill, etc., can be overcome easily by proper training, the human attitude and mindset towards asset failure is somewhat difficult to handle. It takes a lot of effort and time to create the right culture.

h) Repair Documentation

Repair documentation - what we did, with some details - is very important when performing an analysis. We often see entries such as "Pump broke - repaired" or "Mechanical seal replaced." Such entries merely help in maintaining failure statistics, but not in failure analysis.

The challenge is usually how to make data input easy for our crafts personnel. For a good reliability analysis, we need to have quality data to understand how the asset was found before and after the failure, what actions were taken to repair, parts used, time taken to repair, etc.

i) Designing for Reliability and Maintenance

If the asset is being modified or replaced, make sure that the operators and maintainers are involved with design reviews and are part of the improvement team. The asset should be designed with high reliability and ease of maintenance features. This best practice will be discussed in more detail in later Section 6.

TPM maintenance practice will be discussed in more detail in Section 7.

5 Maintenance Management System: CMMS

A maintenance management system is an essential tool for all maintenance organizations. It can help to improve a maintenance department's efficiency and effectiveness and, ultimately, to get more out of assets by streamlining critical workflows, work identification, work task planning, scheduling, and reporting. Two types of systems are available. One type of system is an enterprise-wide collection of modular applications such as asset management, material resource planning, finance, and human resources. These applications or systems interface with each other seamlessly and can work effectively across many locations and plants. Most of these systems, first developed in the mid-1990s and throughout the following decade, are known as Enterprise Asset Management (EAM) systems. Examples of these types of systems are those from companies such as J.D. Edwards, IFS, Oracle, PeopleSoft, and SAP. They can be expensive to install as well as keep up-to-date.

Other types of systems are standalone applications related to maintenance management. They can be interfaced with other enterprise-wide systems such as Finance or Human Resource systems. These systems are called Computerized Maintenance Management Systems (CMMS). The CMMS name was coined in the late 1970s and 1980s when PM programs were automated using computers. New CMMS systems have a lot more capabilities and functionalities; they are easier to use compared to some EAM systems. Examples of these systems are assetPoint, Champs, DataStream, eMaint, EPEC, Ivara, Maximo / IBM, Mapcon, mPulse, and Synergen/SPL/Oracle WAM. Over a hundred systems are available in the market, starting from $1,000 to over $250,000 depending upon the number of users or the size of the plant. Most of these systems are now web based. Basically, now there are no major differences in the way both types of systems function so the terms CMMS and EAM are often used inter changeably.

CMMS / EAM systems should have the following capabilities, al though they are not limited to them:

1. Asset / Equipment History

2. Asset description and specifications

3. Asset Register

4. CM results of PM and CBM findings

5. Configuration Management

6. Contractor Work Management

7. Critical asset identifications

8. Drawing and technical document management

9. EPA/OSHA permits

10. FMEAs and RCM analysis history

11. Hierarchy management

12. Inventory / spares management

13. Materials - MRO Stores Management

14. MTBF and MTTR data by assets and asset types

15. Non-recurring work - failures / breakdowns

16. Pending work – Backlog

17. People Management

18. PM and CBM/PdM Work Procedures

19. PM Optimization including Reliability Analysis

20. Pressure vessel certifications

21. Recurring type work - PM, PdM/CBM

22. Reporting - Standard and Specialized Reports

23. Timekeeping

24. Training management

25. Warrantee management

26. Work Order routing

27. Work close-out and feedback

28. Work estimating data tables and link to other resources

29. Work Identification

30. Work Order (WO) Management

31. Work planning

32. Work scheduling and resource balancing

Work Order (WO) Management Module

One of the most useful management tools in a CMMS package is work order (WO) management or workflow process. The workflow engine allows automatic routing of data through an optimized process, including configurable approvals, notification, and automated transactions based on user-defined business rules.

A standard workflow for routing work orders to the appropriate approver, depending on estimated total labor and material dollars, can be established. Furthermore, organizations can establish work limit rules by teams and approval type for customizing authorization schemes. The sys tem can be set up to request the next level of authorization when the actual dollar expenditure logged exceeds a user-defined percentage. Thus, work orders or projects can be monitored for significant overruns. The system also can be configured to allow only certain people to approve emergency work orders.

Organizations should be able to establish elaborate business rules, if desired. For example, a work order of a certain type and dollar value is sequentially routed to two approvers. If the first approver doesn't approve the work order within a certain time period, the supervisor is notified by email/pager. It also can designate alternate approvers under certain conditions, such as when the approver is on vacation. Other features for work order management may include:

1. Ability to create multi-step WO; for similar work, WO can be saved as a template for future work.

2. Ability to build work standards for labor estimating.

3. Easy to input data including graphical user interface having a similar look and feel as Microsoft office software.

4. Ability to provide status for a given workflow item directly from a table or dashboard.

5. Ability to provide statistics such as volume of transactions that went through a given time period, or the average time to complete a specific work activity.

6. Entering standard times for work activities to predict how long a process should take, and to report on actual versus standard completion time.

7. Making activities mandatory or optional, depending on the characteristics of the work type (e.g., skip the approval step if a work order is urgent).

PM and CBM /PdM Module:

PM and Condition-Based Monitoring is another important module for a CMMS. Some of the features for optimizing the workflow are multiple PM triggers; schedule flexibility that accounts for seasonality, multiple formats, zoom, and simulation; and condition monitoring for user-defined data. Another helpful feature is task shadowing. This feature allows skip ping a weekly PM routine if the short-term schedule has an upcoming monthly routine that includes the same weekly tasks.

Information from data collection systems, such as barcode-based time reporting, Supervisory Control and Data Acquisition (SCADA) system, and Human Machine Interface (HMI) can automatically feed into CMMS the condition of assets and the use of maintenance labor and material. If a variance is detected, it can be explained via drill-down to the source data.

The condition-based maintenance functionality in a CMMS can be used to establish the control limits that trigger actions, such as issuing a work order or paging a technician, thereby increasing workflow efficiency and effectiveness. Most managers find it increasingly difficult to control rising maintenance costs because of inadequate or outdated procedures. The CMMS can identify such procedures that are consuming large resources and need reviews or updates.

Scheduling Module

Scheduling is an area where different CMMS packages provide significant capabilities. CMMS should provide a schedule to match the work demand for maintenance - open work orders with the labor resource availability. Some systems compare the work backlog with a listing of available hours, all similarly sorted and filtered. Some system displays this data in graphs to help in workload balancing. A good way to display this data can be a bar graph in the top half of the screen and the lists of work orders in the bottom half. Some CMMS packages increased their level of sophistication by seamless linkage to home-grown or third-party project management soft ware. This gives users access to comprehensive features such as critical path analysis, Gantt charting, and resource utilization optimization.

Probably the most exciting breakthrough in scheduling functionality is the ability to perform "what-if" analysis. By playing with variables such as estimated duration of work, work order priority, and labor availability, the maintenance scheduler can fine-tune the schedule without having to make a permanent change in the source data. Only after the scheduler and craft supervisors are satisfied with the schedule, the data is frozen and the source data updated.

Productivity and User-Centered Design

One of the most important trends seen in CMMS is the improvement in user-centered design or usability during recent years. For those CMMS packages that rewrote their software to become Web-based, the new, improved user interfaces have become more user-friendly. To compare prospective CMMS vendors, some users have even developed several scenarios to assess how many screens it takes to complete a given series of tasks and over what time. Some compare how many screens or clicks are typically needed to get the information they need. The Web-based soft ware packages offer much improvement over older systems, with features such as:

1. Search toolbar


3. Favorites

4. History pull-down, which provides a listing of screens that were visited in the past, in chronological order, including hyperlinks

5. Back and Forward buttons to move through the last viewed screens

6. URL toolbar, which allows the user to key in any screen address or Web site reference (like a "go to" feature)

Another key trend in user-centered design has been the flexibility in customizing the application to the varying needs of individuals, or tailoring it to different roles such as maintenance planner, scheduler, supervisor, craftsperson, and stock keeper. This trend has been widely accepted by users, as it decreases training time, simplifies execution of day-to-day processes, improves accuracy and speed of data entry, and facilitates extraction of relevant information that lead to better and faster decision making. Examples of customization capability are:

1. Security access that defines who has the access to certain fields, screens, menus, etc., and whether data is read-only or even visible on-screen

2. Screen layouts including what fields are viewed on which screen or tab, field labels, size and shape of each field, field position, colors, tab labels and content, size and position of columnar data, and default values

3. Language that a package displays, as well as currency used

4. Start-up or main menu, i.e., what menu options, shortcuts, report asset lifespan. Repair vs. replace analysis can be shown graphically, where the cost of a new asset exceeds the historical trend cost of repairing it, all based on a user-defined amortization period and inflation rate.

Many CMMS vendors have been trying to improve their failure analysis capability in response to the ever-increasing interest in failure modes and effects analysis (FMEA), reliability-centered maintenance (RCM), and root cause analysis (RCA). Asset-intensive organizations are finding it painfully slow and complex to implement these advanced techniques. When these techniques are used on critical assets and systems, the potential payback is enormous.

Another group of analysis tools for which demand is steadily growing includes costing and budgeting tools such as life-cycle costing. Capturing costs associated with an asset, from its procurement to its disposition, gives management greater insight into the total cost of ownership or economic life of various assets and asset classes. The benefits of tracking life cycle costs are many, including:

• Comparing the cost of various offerings of the same asset type before e.g., comparing, say, a Caterpillar versus a Toyota forklift with the same or similar specifications)

• Understanding the trade-off between asset performance and the total cost of ownership (e.g., deciding how long it’s economical to hold onto a specific asset and when is it economical to replace it)

• Forecasting cost of assets based on the life-cycle cost profile of similar assets

• Becoming aware of the costs in order to control them Life-cycle cost analysis can be quite complex, especially for facilities or infrastructure that require monitoring and assessment of the asset's condition and rate of deterioration. The multi-year considerations include factors such as discount rates used in the net present value (NPV) calculations. Important assumptions about how the business, market and product alternatives will change over time.

A CMMS can help in tracking life-cycle costs by accumulating relevant labor, material, contract, and overhead costs associated with a given asset - even if the asset is moved, sent outside for repair, shows sign of deterioration faster or slower than expected, or either depreciates or appreciates in value. Costs other than maintenance costs must be considered; these include installation costs, operating costs, and risk abatement (e.g., health, safety, and environmental impact).

Mobile Technology

The popularity of mobile technology continues to rise as more users realize its power. Meanwhile, the telecommunications networks continue to expand their geographic reach and their ability to handle interference.

Handheld devices are also improving in terms of functionality and afford ability. Much of the functionality of a desktop terminal can be put in the hands of a mobile user, including uploading and downloading work order and spare parts inventory information, accessing equipment history and reports, and even viewing or redlining drawings and maps. The mobile technology is one of the most important trends being adopted in the CMMS industry, just as the BlackBerry, Smartphones and IPads took the business world to a whole new level.

System Affordability

The need for and use of a CMMS is not specific to any one industry or type of application. Any organization using assets to make products or providing services is a potential candidate for a CMMS. Computerized systems are becoming more attractive as more maintenance personnel have become computer literate and prices of hardware and software have dropped significantly. These factors make a CMMS an attractive option for even smaller plants. CMMS packages are available in modular format. In other words, organizations don't have to buy all the modules and options. For example, smaller plants can purchase only the asset, PM, and work order modules to start. They can add other modules later on. Also, many CMMS programs are designed with scaled-down functionalities for smaller plants. These programs are fully functional and relatively inexpensive. However, organizations must determine if a CMMS is beneficial to their operations and have buy-in from all stake holders.

Workforce average age and continuity of the organization's knowledge base is another important issue to consider. How much information will leave the company when a key maintenance employee retires? Years of critical information can be lost the moment that employee walks out the door.

Barriers to CMMS Acquisition

Opposing the CMMS acquisition are the internal roadblocks that stand in the way of the system purchase, particularly in smaller organizations. The following list can help overcome barriers associated with acquiring a CMMS:

1. Organization is too small for a system. - This attitude suggests a basic lack of understanding of the true benefits and functions of a CMMS.

A CMMS that is ideally matched to the organization's needs should pay for itself, even for very small plants. There are many plants with just a few maintenance technicians successfully using a CMMS. A CMMS can help record and maintain the equipment histories that will be the basis for future repair vs. replacement decisions and associated justifications. An accurate and complete history can also describe how the job was executed last time, thereby, saving time associated with a job or task redesign.

2. The project payback or savings is inadequate. - Maintenance organization must do a thorough job of determining benefits and savings in order to show real ROI of a well-chosen CMMS.

3. MIS or IT doesn't give CMMS high enough priority. - This lack of sufficient support is a very common situation. If MIS supports the project, its chances of success are increased greatly. A CMMS is complicated to many decision makers. Helping MIS understand the importance of CMMS should be a primary goal of the maintenance department.

4. MIS and maintenance speak different technology languages. - Being able to translate the technological and business benefits effectively can go a long way toward overcoming this roadblock. With MIS support, it’s easier to convince others.

5. Participants fail to reach consensus. - When the parties involved disagree on either the need for a CMMS or the features required in a CMMS, it becomes difficult to gain approval for CMMS funds.

There must be an internal champion who is empowered to select a team and act on results.

Selecting the Right CMMS

Selecting the right CMMS is crucial to a successful implementation.

Some suggested guidelines are discussed below.

System Features:

There are numerous features that the system should include. One such feature is flexibility. The CMMS should be flexible in terms of allowing users to enter information pertaining to your organization. It should also accommodate both present and future needs. Organizations should also be aware of the system's limitations. Before buying a particular system, one should check the limitations of the system. For example, if the number of records in the database increases significantly in the future, the system's searching and reporting capabilities should not be slowed down.

Another feature to consider is the system's interfacing capabilities.

The CMMS should be capable of interfacing with other information systems. Self-sufficiency is something else to consider. Programs should be capable of direct, full use without needing to consult a manual or other outside sources. The on-screen instructions should explain what the pro gram will do and how to use it. Other features to consider include the system's security, data security, modifications, user customizable screens, and user customizable reports.

Ease of Use:

The CMMS should be easy to learn and should come with training aids and documentation. It should also be easy to use. The package should be icon and menu driven, contain input screens to enter information in an orderly manner, and provide error handling and context-sensitive help.

Vendor Support Consider the qualifications of the potential CMMS vendors.

Obviously we want a vendor who is both knowledgeable and experienced when it comes to CMMS. Also consider the vendor's financial strength. A CMMS project is an investment in time, resources, and money. Therefore, the vendor must be established. Ask about references, delivery, payment options, source code, and warranty.

Also, investigate the level of vendor support for training. Whether this training is provided at their facility or on site, this small investment can save a great deal of money and frustration in the long run. Other factors to consider include the vendor's system support, upgrade policy, and over all system cost. Select the vendor that provides the best combination of characteristics for your particular situation.

The bottom line is that there a need for a CMMS for maintenance no matter how small or large plant is. We should be aware of the barriers and be well prepared to face them during the justification process. We can avoid failure by looking at why so many installations have failed and making the right selection for application for the organization.

Why So Many CMMS Projects Fail:

Many CMMS projects fail to reach their full potential.

The following are some of the reasons:

1. Selecting the wrong CMMS for your application

2. Employee turnover

3. Lack of adequate training during implementation

4. Employee resistance

5. Being locked into restrictive hardware/software

6. Inadequate supplier support for the CMMS

7. High expectations and quick return on investment

8. Internal Politics - Financial or IT - heads the CMMS/EAM implementation team

Note: Ideally, senior M&R professionals should lead the project because they understand the need more than anybody else. Keep IT and Finance employees on the team to get their continued support.

In general, incremental gains in CMMS features and functions have made many packages better at handling the myriad and specialized requirements of particular industries and facilities. Many organizations are simply looking for a CMMS package that meets their unique needs, and a vendor that understands their industry. Some examples are as follows:

1. Pharmaceutical organizations require a CMMS that has an electronic signature capability to comply with FDA 21 CFR Part 11.

2. Municipalities are looking for a CMMS package with sophisticated linear asset functionality for handling utilities, underground water and wastewater networks, and so on. They need capability to be in compliance with GASB 34 requirements.

3. Organizations with considerable mobile equipment are looking for fleet management functionality, such as compliance with the vehicle maintenance reporting standards (VMRS) coding structure or the American Trucking Association's standard listing of components.

4. Pipeline companies need inspection and risk assessment features.

5. Chemical, oil and gas, and nuclear plants need sophisticated safety-related functionality such as lockout/tag out.

6. Third-party service providers want features such as contract management, third-party billing, help desk, and dispatch.

7. Government departments are keen on sophisticated budgeting capability including encumbrance accounting.

8. Asset-intensive companies experiencing considerable capital expansion can save millions of dollars if the CMMS can help integrate and follow the complete life cycle of asset-related data from engineering design to deployment to maintenance.

An effective CMMS has proven to be an invaluable tool for many plants and facilities. Various internal obstacles to acquiring a CMMS also confront businesses. When deciding to acquire a CMMS, take the following steps:

a. Form a team.

b. Identify problems with the existing system.

c. Define the objectives, features, and benefits of a CMMS.

d. Conduct a financial analysis.

And identify a project manager, preferably a senior M&R profession al, not an IT or financial person, to lead the project.

New CMMS packages are so feature-rich that most users can hope to exploit only a small percentage of the functionality they buy. It has been reported that most of the users utilize less than 50% of the capabilities and functionalities of the CMMS they have. The true differentiation is how the CMMS is implemented. Organizations should set quantifiable goals and objectives, re-engineer processes in light of those goals, con figure the CMMS to optimize the new processes, and change behavior across organization to embrace these changes.

6 Maintenance Quality

It’s said that "Accidents don’t happen, they are caused". The same is true for asset failure. Assets fail due to basically two reasons: poor design and human error. Our negligence, ignorance, and attitude are the prime factors of human errors. Several studies have indicated that over 70 percent of failures are caused by human errors such as overloading, operational errors, ignoring failure symptoms and not repairing an asset when it needs to be taken care, and the skill level of our work force. There is usually a human factor behind most asset failures. Because most failures are caused and don’t happen independently, they are preventable.

If a survey is taken among operations and maintenance personnel as to whether there can be zero failures, the overwhelming answer will be zero failures are theoretically possible, but impossible in an actual work environment. Yes, zero failures are difficult to achieve, but they may not be impossible. If all concerned operations and maintenance personnel set a goal of zero failures and diligently work toward that goal, it’s attainable.

However, total commitment is needed from all involved, from top management to supervisors and down to the operator and maintainer level.

What we need to do is implement some good and best practices, as well as strict adherence to the procedures.

Quality of Maintenance Work:

All maintenance work involves some risk. Here, the risk refers to the potential for inducing defects of various types while performing the maintenance tasks. In other words, human errors made during the PM, CBM, and CM tasks eventually may lead to additional failures of the asset on which the maintenance was performed.

For example, a review of the data from the power plants that examined the frequency and duration of forced outages after a planned maintenance outage reinforces this risk. The analysis of data showed that in 55% of the cases, unplanned maintenance outages were caused by errors com mitted during a recent maintenance outage. Most of the time these failures occur very soon after the maintenance is performed. Typically, the following errors or damages may occur during PMs and other types of maintenance work.

Damage to the asset receiving the PM task may include such things as:

• Damage during the performance of an inspection, repair adjustment, or installation of a replacement part.

• Installing material/ part that is defective

• Incorrectly installing a replacement part, or incorrectly reassembling

• Reintroducing infant mortality by installing new parts which have not been tested

• Damage due to an error in reinstalling asset into its original location

• Damage to an adjacent asset or component during a maintenance task

A quality maintenance program requires trained and motivated maintenance personnel. To create high quality and motivated personnel, the following measures are suggested:

a. Provide training in maintenance best practices and procedures for maintenance on specific assets.

b. Provide appropriate tools to perform the tasks effectively.

c. Get them involved in performing FMEA and RCA/RCFA, and in developing maintenance procedures.

d. Follow up to assure quality performance and to show everyone that management does care for quality work.

e. Publicize reduced costs with improved uptime, which is the result of effective maintenance practices.

7 Maintenance Assessment and Improvement

Maintenance Key Performance Indicators (KPI)

It’s often said that "what gets measured gets done" and "If we can't measure it, we can't improve it." KPIs, also called metrics, are an important management tool to measure performance and help us make improvement actions. However, too much emphasis on performance indicators, or on the wrong indicators, may not be the right approach. The selected indicators shouldn't be easy to manipulate just to "feel good." The following criteria are recommended for selecting the best KPI / metrics:

• Should encourage the right behavior

• Should be difficult to manipulate

• Should be easy to measure -- data collection and reporting

Some key maintenance metrics, with some benchmark data, are listed in Figure 1.

Fig. 1 Maintenance Benchmarks

Other maintenance metrics to consider, depending on the maturity of the maintenance program, include:

• PM and CBM effectiveness, or the number of hours of corrective work identified by PM and CBM work divided by hours spent on PM and CBM inspections. The PM and CBM should be able to identify 1/2 - 2 hours of corrective maintenance work to every one hour of PM and CBM performed; otherwise, the frequency or condition parameters should be reviewed or adjusted.

• PM and CBM schedule adherence. It should approximate 90% or more.

• Percent of maintenance labor dedicated to performing PM and CBM inspections should be more than 50 percent. The rule of thumb is:

• PM - Time based 15-20%

• CBM 30-40% - The distribution may vary depending on type of asset and industry.

Maintenance Task Optimization:

Maintenance effectiveness can be improved by optimizing the maintenance work tasks (content) and by effective task execution through the utilization of the many tools available to us. The maintenance tasks - e.g., PM, CBM work instructions, and repair plans - must cover what needs to be done. These tasks can be optimized by using tools and techniques such as FMEA, RCM, and predictive technologies. These tools and techniques can help to optimize the content of the work tasks to be accomplished.

Establishing a Successful Maintenance Program

Scheduling and execution are the keys to a successful maintenance program. Maintenance programs should be automated by using Computerized Maintenance Management Systems (CMMS) or Enterprise Asset Management (EAM) systems. In addition, a monitoring process should be established to ensure a 90% or better schedule compliance and quality of work performed.

In addition, create a "living maintenance program" consisting of the following key elements:

• Continually review processes, procedures, and tasks for applicability, effectiveness, and interval frequency; these should be optimized as required. Get the right people both in operation and maintenance involved in the review process.

• Standardize procedures and maintain consistency on asset and components.

• Identify and execute mandated tasks to ensure regulatory compliance.

• Apply and integrate new predictive technologies where effective.

• Ensure task instructions cover lockout / tag out procedures and all safety requirements.

• Ensure operation and maintenance personnel understand the importance of PM practice and provide feedback for improving PM instructions and procedures.

8 Summary

Maintenance prevents an asset or item from failing and repairs it after it has failed. However, the new paradigm for maintenance is capacity assurance, meaning that maintenance assures asset capacity as designed or to an acceptable level.

Maintenance approaches - practices can be classified in the following categories:

• Condition-based Maintenance (CBM)

• Preventive Maintenance (PM)

• Time (Calendar) based maintenance (TBM)

• Run-based maintenance (RBM)

• Operator-based maintenance (OBM)

• Proactive maintenance

• Corrective Maintenance (CM)

• CM - Planned and Scheduled

• CM - Major Repairs / Projects (Planned and Scheduled)

• CM - Reactive (Breakdowns / Emergency)

Computerized Maintenance Management Systems are essential data based decision making tools for managing asset. A CMMS or EAM sup ports a maintenance department to ensure that assets and systems operate efficiently, and to minimize downtime. They help to improve maintenance effectiveness in any organization.

All maintenance tasks involve some risk of introducing defects of various types while performing the maintenance tasks. In other words, errors committed during the PM, CBM, and CM tasks eventually may lead to additional failures of the asset on which the maintenance was performed.

A maintenance quality program requires trained and motivated maintenance personnel.

Selecting the right performance indicators to measure maintenance performance is critical and important to implementing best practices. The indicators should encourage the right behavior; they should be difficult to manipulate just to have "feel good" results. Finally, they should be easy to collect and report.

Maintenance cost and asset availability can be improved by optimizing the maintenance work tasks (content) and by effectively executing tasks through the utilization of tools available to us. Maintenance tasks such as PM/CBM work instructions and repair plans must cover what needs to be done. These tasks can be optimized by using tools and techniques such as RCM, FMEA, predictive technologies, and Six Sigma.

These tools and techniques help to optimize the content of the work tasks to be accomplished. The execution of maintenance tasks can also be optimized by using other tools and techniques such as planning and scheduling. These tools and techniques can help to utilize maintenance resources effectively.


1 Define maintenance and its role.

2 What are the different categories of maintenance work?

3 What can equipment operators do to support maintenance?

4 Why would an organization support operators getting involved in maintenance?

5 Why would an organization need to have a CMMS? What is the difference between a CMMS and an EAM?

6 List five maintenance metrics and discuss why they are important.

7 Name five PdM technologies. Discuss how they can help reduce maintenance costs.

8 Define Proactive Maintenance.

9 What are the benefits of a structured maintenance program?

10 How can a CMMS/EAM system help improve maintenance productivity?

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