SPECIAL REPORT: CMMS improves refining maintenance management

To operate a world-class maintenance organization, plant operators need precise information combined with the ability to act quickly in response to impending emergencies. A computerized maintenance management system (CMMS) can help refiners eliminate the vast majority of unscheduled equipment repairs.

This article discusses the features of a CMMS that are important for plant owners to demand.

The main objective of maintenance management is to achieve the optimum balance between plant availability and maintenance resource use. The effective matching of labor and material resources for maintenance planning and control is a dynamic activity.

Plant management needs reliable information of both equipment performance and costs, which will allow them to make informed decisions. It is therefore essential to adapt to techniques that would provide accurate and timely information for making the maintenance function more meaningful and reduce the unforeseen plant outages.

Implementation of a computerized maintenance system is an effective way to achieve this goal. Selection and proper implementation of the correct CMMS is an integral part of achieving maintenance management success.

CMMS

The maintenance department should:

• Provide effective maintenance services that support facility operational requirements.
• Reduce unscheduled equipment downtime through effective maintenance planning.
• Use the CMMS report generator to provide meaningful management reports that will increase the control of maintenance activities.
• Use CMMS to ensure that maintenance is performed efficiently through organized planning and the coordinated use of materials, manpower, and time.
• Create and maintain measurements of maintenance performance within CMMS.

One of the highest priorities of a maintenance manager should be keeping the equipment operating (reducing equipment downtime). The corresponding goal is to reduce downtime by some percentage.

Assuming that a CMMS package has provisions for entering and tracking downtime, the operator should carefully log all downtime and enter the information in CMMS; total as well as specific equipment downtime can be retrieved and compared with last month’s, last year’s, or last week’s.

Objectives should be to measure and maximize maintenance program effectiveness. Specific areas for measurement should include percent of rework, percent of planned maintenance work, and percent of unplanned maintenance work. The maintenance manager should establish standards that will assign actual costs for equipment downtime and then track both planned and unplanned downtime.

The CMMS should include the following options.

Asset management, register

This option will facilitate the creation of an asset register. The asset register holds comprehensive details of each asset or piece of equipment.

Typical data stored include asset number, department, asset name, model, serial number, drawing numbers, purchase price, location, supplier, planned and unplanned maintenance history, etc.

Preventive maintenance

Maintenance schedule should have a flexible set up, allowing each asset to have a defined maintenance profile. This may include details of various periods, trades required, procedures required, estimated job times, and when the equipment is available, etc.

The preventive maintenance (PM) procedure library is generally a database of all the PM procedures required for the maintainable assets in the system. In a paper system, records contain details of PM to be carried out on all equipment. Each time maintenance is scheduled, the technician must refer to the procedure on file.

The operator generally desires a system that allows many assets to be linked to a single procedure that is convenient to use. If the procedure requires modification, it should be done only once and all linked assets will continue to use the modified version in the library.

Unplanned work reporting

When a defect or breakdown occurs, someone from production must notify the required trade group. This is done through the nearest terminal by inputting brief details of the fault, the asset number or description, and the reporter’s name.

When this is done the software offers the reporter a choice of printers. After one has been selected the work order is printed in the relevant workshop. The work order is then automatically added to the list of outstanding work.

Scheduling planned maintenance

Most systems include a maintenance scheduler. When the scheduler runs, it scans each asset in turn and checks the periods when maintenance is required. It then looks at the last maintenance date for each period and, if due, creates a planned maintenance work instruction for the asset.

Typically, the planned maintenance scheduler will be “rolled forward” each week, producing work instructions and adding them to the list of outstanding work. Users may be required to decide whether they would prefer the scheduler to run automatically, in real time, or by intervention at a particular time each day or each week.

Work orders

In addition to generating unplanned work orders, the CMMS should have a means of outputting hard copies of planned work orders. The system should separate the planned work orders into various trades, asset groups, and locations before they are printed.

Other points are whether the user requires work order formats to be reconfigurable. Most companies want to design their own work order forms.

Viewing outstanding work

Maintenance managers and supervisors need to check outstanding work orders quickly. The system should support a quick and easy method of selectively displaying lists of these work orders by trade, work type, department, etc.

Purchasing

Most fully integrated packages support some kind of inventory-management option. If this option is used, the operator should carefully specify it to ensure that it meets local requirements.

One benefit of opting for stock control is that trade groups can have access to the inventory database allowing them to find spare part numbers and check stock levels of maintenance spares. Some systems allow spares to be linked to equipment, thus simplifying the search and ensuring that no obsolete spares are held in inventory.

Some users consider that the greatest financial returns from a CMMS are through improved stock control procedures.

Condition monitoring

Condition monitoring is a form of predictive maintenance in which continuous monitoring of the condition of specific areas of plant and equipment occurs. When any predefined limit is exceeded, an alarm output is turned on. This alarm output can be input to a CMMS so that a work order is generated immediately. This is particularly suited to continuous processing where plant failure could be extremely costly.

Typical conditions that can be monitored are temperature, vibration, over voltage or current, and liquid level—any condition that a sensor can detect.

Statistical data, reports

CMMS has extensive information readily available for fault analysis, costing, and work statistics. This is one of the most important functions of a CMMS.

Lube data

Maintenance procedures should, at a minimum, indicate the type of lubricant. If the requirements were taken from manufacturer’s literature, the procedure probably includes the lubricant manufacturer, grade, and brand name.

Importing all lubricant data and application requirements into the CMMS allows the operator to develop a lubricant equivalency matrix, which he can use to minimize the number of different brands and grades needed and probably reduce the total quantity kept on hand by about 50%.

A single lube map can take the place of several procedures, which a lube team can perform in much less time and in fewer separate efforts. Consolidating lubrication requirements is an obvious cost-saving practice.

Daily scheduling, job control

This covers areas such as how work is allocated to the workforce, and how a “reasonable” time for job completion is generated. It also includes how daily priorities are set and decisions made regarding the deferral or cancellation of planned work to incorporate daily breakdowns.

Weekly scheduling

An effective weekly scheduling system permits the allocation of jobs to specific days, so that parts can be delivered to the job site “just in time,” and so that equipment can be shut down and cleaned before the tradesman arrives to perform the maintenance task.

It also compares labor requirements of the schedule with labor available from the work crew for each day of the schedule, and allows effective decision-making regarding the need for supplementary labor or the need to reschedule work before the schedule is finalized.

Maintenance budgeting

Maintenance activities generate maintenance costs, and although some sites prepare maintenance budgets based on a bottom-up assessment of maintenance activities they expect to perform, few report actual costs vs. those budgeted activities. Most CMMSs only permit the reporting of actual costs against budgeted amounts; therefore an essential element of cost control is lost because the manual effort involved in reconciling the budgeted activities with those actually performed means that this task is not performed.

This being the case, the budgeting and cost control procedure should clearly be “owned” by these people, with people at this level responsible for preparing maintenance budgets and controlling costs to within those budgets.

Maintenance effectiveness

Included in this process are activities such as failure analysis and reliability-centered maintenance (RCM) analysis.

To make informed decisions regarding equipment maintenance strategies and equipment design modifications, one must record information about:

• The number of failures.
• Root causes of those failures.
• Maintenance costs associated with those failures.
• Production costs associated with those failures. These may incorporate more than just downtime costs.
• Any safety or environmental implications associated with those failures.

When evaluating CMMSs, there are five major factors that one must consider. Careful examination of these factors during the evaluation process will help ensure ongoing CMMS success:

1. Comprehensive maintenance management functionality. This should include three major elements: work management, physical asset management, and resource management.

The work management component of CMMS optimizes day-to-day operations, manages corrective work orders, and supports a PM program

The physical asset management component acts as the “filing cabinet” of CMMS, providing quick and easy retrieval of important information such as: planned and unplanned work history, assets accounting information, warranty and service contracts, nameplate data, scanned documents, libraries of computer-aided drawings, and complete descriptive information.

The resource management component of a CMMS supports a full inventory and purchasing system. Furthermore, it tracks in-house labor and contracted service costs.

2. Extensive management reporting capabilities. CMMSs provide extensive management reporting capabilities that include detailed and summary reports, graphical reports, and easy-to-use report writing tools that do not require programming knowledge.

3. PM procedure library. This will minimize the start-up time necessary to establish and implement a PM program and provide conformance to generally accepted PM inspection schedules. After many PM actions have been performed and recorded on the same equipment, sufficient data is available for determining whether the equipment needs more or less frequent PM work and how PM frequency should be adjusted.

4. Multiple system interfaces. The CMMS should be able to work together effectively and transparently with multiple systems. Direct interfaces between the CMMS and other diagnostic and monitoring systems such as predictive maintenance can assist greatly in streamlining the maintenance process by allowing maintenance personnel to respond to early warning signals before they escalate into critical repair problems.

A CMMS builds on these types of interfaces to automatically create work orders and update equipment histories based on alarms and test results received through these interfaces.

5. RCM integration. The CMMS system should fully integrate and take advantage of RCM.

In selecting a CMMS, the operator should conduct a formal review to determine the key performance indicators (KPIs). Then the operator must consider where the data to produce these KPIs is going to come from.

Frequently these KPIs will require data from different systems; for example, maintenance cost/tonne may require data from the CMMS or accounting system and the production systems. Maintenance safety statistics may need data from a totally separate system.

Reliability and maintainability indicators should look better in a CMMS. The mean time between failures (MTBF) should increase and the mean time to repair (MTTR), if managed correctly, should stay at the pre-implementation low level.

A maintenance workforce in a reactive state will have a very low MTBF of equipment and an equally low MTTR. This may be masked, if not measured and regularly reported, by the fact that machine availability may still be at a high level.

What the indicator shows is that a plant or piece of machinery is unreliable and breaks down often; and that workers are good at fixing these breakdowns. The culture that is fostered in these situations can be the most difficult obstacle in the implementation of a CMMS and realizing its possible gains.

Machine availability

With the amount of day-to-day data available in a CMMS that pinpoints problem areas and modifies processes and routines, other factors are easier to achieve. A reduction in the amount of breakdown work, or increase in overall availability of plant and equipment, of 5% is a realistic and achievable goal.

Inventory holdings

As the work content becomes more planned out, the inventory department will become more predictive. The will reduce the requirement to keep large volumes of parts and materials on a “we might need it” basis.

If the plant owner can reduce inventory, the logistical requirements to manage the inventory function also decreases dramatically, particularly that of the purchasing department and actual inventory management personnel.

RCM

A CMMS should have the functionality to support RCM. RCM is the method that best addresses the requirement for maximum reliability at minimum cost, or more pragmatically, doing the right maintenance at the right time.

RCM results in a maintenance program that focuses PM on specific probable failure modes only. It has a strong bias toward condition monitoring and trend analysis of equipment performance.

Nonintrusive condition monitoring, such as vibration monitoring and oil analysis, can reveal deterioration in performance and warn of impending loss of equipment functionality or failure. When sufficient data are available, the operator can use trending and perform maintenance when measurements stray out of a predetermined safe operating range.

Performing appropriate maintenance just in time can produce significant cost savings, in addition to increased equipment uptime. RCM is a powerful tool for optimizing just-in-time maintenance actions.

RCM targets only preventable failure causes with actions intended to prevent them, predictable failure mechanisms with actions that take advantage of the predictability of the mechanism, or telltale signs that indicate that the failure mechanism is in its early stages so that the operator can take steps to prevent functional failure. RCM does not result in overmaintaining equipment with actions that do not address specific failure modes.

RCM can result in significant reductions in direct maintenance costs.

Maintenance measurements

One of the universal objectives of any maintenance improvement plan must be to improve the ratio of planned vs. unplanned work. The ultimate goal is to have no unplanned maintenance.

In practice, many unorganized maintenance departments will have a ratio of 90% unplanned to 10% planned work; much of their work will be reactive. A CMMS will make this easy to monitor and produce a suitable measurement. Over time, it can be used, along with the other statistics, to reverse the trend.

Many other maintenance factors that have relevance, including:

• Percent overtime hours.
• Cost of maintenance.
• Backlog of work.
• Average time per breakdown job.
• Cost of spares.
• Cost of labor.
• Equipment effectiveness.
• Total maintenance cost per unit of output.
• Cost of lost output due to unplanned downtime.
• Cost of lost output due to planned downtime.
• Downtime percentages, by area and by asset.
• Mean time between stops or MTBF.

Future of CMMS

In the future, users of CMMS will demand these additional functions:

• Planning indicators and capabilities.
• Automatic scheduling as a forecast of man-hour capacity levels.
• Automatic scheduling according to materials availability levels.
• The ability to schedule work on the basis of equipment operation or condition.
• Control of inventory levels and materials planning for 3-5 years.
• Equipment condition monitoring and alarm generating capabilities.
• Asset register creation and the inclusion of equipment or component tracing capabilities.
• Project management capabilities.
• Shutdown planning capabilities.

Predictive maintenance

Ideally, the plant operator should integrate the CMMS with a predictive maintenance system. At a minimum, the predictive maintenance system should accurately monitor real-time equipment performance and alert the maintenance professional to any changes in performance trends.

There are many measurements that a predictive maintenance package could track including vibration, oil condition, temperature, flow, etc. CMMS is a great organizational tool but can not directly monitor equipment condition.

A predictive maintenance system excels in monitoring equipment condition. It is ideal to combine the two technologies into a seamless system that avoids catastrophic breakdowns but eliminates needless repairs to equipment that is running satisfactory.

Based on a presentation to the Oil & Gas Maintenance Technology Conference & Exhibition, Dec. 9-13, 2007, Manama, Bahrain.

The author

Trinath Sahoo ([email protected]) is a manager for Indian Oil Corp. Ltd., Haldia. Since 2003, he has worked in the maintenance department for the Haldia and Mathura refineries. Sahoo’s responsibilities include troubleshooting of rotary equipment, planning, scheduling, and controlling maintenance activities. During 1994-2003, he worked in the engineering services department at the Haldia refinery. Before joining Indian Oil, he was a senior engineer for Indian Charge Chrome Ltd. Sahoo holds a BSc in engineering from the University College of Engineering, Orissa, India.