Maintenance and Reliability Best Practices. Ramesh Gulati
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• Installation of material or a part that is defective
• Incorrect installation of a replacement part or incorrect reassembly
• Reintroduction of infant mortality by installing new parts that have not been tested
• Damage due to an error in reinstalling an 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:
1. Provide training in maintenance best practices and procedures for maintenance on specific assets.
2. Provide appropriate tools to perform the tasks effectively.
3. Get personnel involved in performing FMEA and RCA/RCFA and in developing maintenance procedures.
4. Follow up to assure quality performance and to show everyone that management does care about quality work.
5. Publicize reduced costs with improved uptime, which is the result of effective maintenance practices.
Maintenance Assessment and Improvement
Maintenance Performance Indicators
It is often said, “What gets measured gets done” and “If we can’t measure it, we can’t improve it.” Performance indicators (PIs), also called metrics, are an important management tool to measure performance and help us make improvements. However, too much emphasis on performance indicators, or on the wrong indicators, may not be the right approach. A few vital indicators are known as KPIs—key performance indicators. The selected indicators shouldn’t be easy to manipulate just to “feel good.”The following criteria are recommended for selecting the best PI/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 3.6.
FIGURE 3.6 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 ½ to 2 hours of corrective maintenance work for every 1 hour of PM and CBM performed;otherwise, the frequency or condition parameters should be reviewed or adjusted.
• The PM and CBM schedule adherence. It should approximate 90% or more.
• Percentage of PM based on reliability/RCM and RBM methodology.
• Percentage of maintenance labor dedicated to performing PM and CBM inspections—this should be more than 50%. The rule of thumb is:
• PM—time- or run-based; 15 to 25%.
• CBM—0 to 40%. The distribution may vary depending on the type of asset and industry.
Maintenance Task Optimization
Maintenance effectiveness can be improved by optimization of 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 CMMSs or EAM systems. In addition, a monitoring process should be established to ensure a 90% or better schedule compliance and quality of work performed.
The following steps are essential for creating a living maintenance program:
• Continually review processes, procedures, and tasks for applicability, effectiveness, and interval frequency; these should be optimized as required. Get the right people in both operations and maintenance involved in the review process.
• Standardize procedures and maintain consistency on assets and components.
• Identify and execute mandated tasks to ensure regulatory compliance.
• Apply and integrate new predictive technologies where effective.
• Ensure task instructions cover lockout/tagout procedures and all safety requirements.
• Ensure operations and maintenance personnel understand the importance of PM practice and provide feedback for improving PM instructions and procedures.
Future of Maintenance: Where Is Maintenance Heading?
We are going through a new Industrial Revolution called Industry 4.0, also known as digitalization. It seems maintenance and reliability are also facing many changes at a very fast pace. Fundamentally,maintenance practices have not changed over the years. However, rapid changes in technology introduce new tools every day. As a result, maintenance is reinvigorating itself. Newer tools such as wireless sensors, the Internet of Things (IoT), drones, high-resolution cameras to capture motion amplification, and data analytics can make maintenance much more effective.
Also, there is a rapid increase in a young, new generation entering the operations and maintenance field and reliability. It is encouraging to see Y Gen and iGen in the workforce, as they are very adaptable to new technology.
Clear evidence indicates that the corporate world has recognized good maintenance programs as a valuable part of total asset management strategy. Many organizations have increased their maintenance budget and are trying to train their workforce to implement best practices.
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 practices can be classified in the following categories:
• Condition-based maintenance (CBM)
• Preventive maintenance (PM)
• Time (calendar)-based maintenance (TBM)
• Run-based maintenance (RBM)
• Reliability—RCM and RBM optimized
• Operator-based maintenance (OBM), also called total productive maintenance (TPM)
• Corrective maintenance (CM)—planned
• CM—planned and scheduled
• CM—major repairs/projects (planned and scheduled)
• CM—reactive (breakdowns/emergency)
Computerized maintenance management systems are essential databased decision-making tools for managing the asset. A CMMS or EAM helps a maintenance department to ensure that assets and systems operate efficiently and 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