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Maintenance
Operator Driven Reliability systems
Prevent catastrophic pump failures
Colin Roberts, SKF Group
The introduction of reliability systems into petrochemical plants is
transforming traditional operating and maintenance practices. Benefits
gained by so-called ‘Reliability Systems’ include substantial financial
savings as well as the prevention of a catastrophic pump failure,
detection of a coolant leak and a doubling of meantime between failure
for critical process fans. SKF’s Colin Roberts reports.
In petrochemical plants two types of reliability systems are proving
highly successful: Operator Driven Reliability (ODR), and Proactive
Reliability Maintenance (PRM). Operator Driven Reliability is a
company-wide, team-based process that optimizes the operation of an
industrial production plant and augments classic operator duties. It
incorporates operational, technical, and financial metrics that are
balanced to best meet the business plan of the industrial enterprise.
Because unscheduled downtime of assets is largely caused by early and
random failures, these failure are best addressed by an Asset Efficiency
Optimization (AEO) program. As a pillar of AEO, Operator Driven
Reliability brings plant operators into a position to assist in the
asset management strategy. A typical ODR program leverages the unique
position that operators hold in the plant, by increasing asset
effectiveness and reducing unscheduled downtime.
Operator Driven Reliability
ODR achieves these goals in two ways:
§ by providing strategic focus for operator responsibilities and duties
§ by ensuring all operator activities have technical, operational, or
financial basis.
The three main elements of ODR are as follows: Equipment Operating
Procedures, Operator Involved Maintenance and Operator Performed
Maintenance.
Equipment Operating Procedures originate from the design of the plant
and the desired performance of the equipment. Plant operators are
responsible for the management and optimization of these procedures.
Operator Involved Maintenance meant to coordinate the operations
department and the maintenance department. This includes activities such
as work orders, equipment changeovers, permits, root cause analysis, and
maintenance strategy reviews. Operator Performed Maintenance activities,
which are generally preventative in nature, use the operators’ unique
understanding of the machine to perform such tasks as inspection,
cleaning, minor adjustments, and keeping a general watch on machine
performance. By doing so, the operator will know when it is time to call
a specialist.
Implementing ODR
Both individuals and management are key to the success (or failure)
of an ODR program. Management change and a clear understanding of the
benefits of an ODR program are necessary throughout the organization.
Correctly implemented, the benifits of ODR include:
§ Providing a basis for operator duties
§ Enabling duties to be tied to business objectives
§ Formalizing of compliance and reporting requirements
§ Fostering operator ownership of assets
§ Improving teamwork and communication
§ Enhancing (or enacting) Total Productive Maintenance and Reliability
Centered Maintenance philosophies
§ Ensuring continuous improvement through an ODR program review
§ Manageable program scope and implementation with impact
§ Increasing asset performance, reliability and effectiveness
§ Increasing revenue and profits
ODR case histories
The Swedish company SKF for instance has extensive experience in
successfully implementing ODR programs in a variety of industries. The
company provides the technology, processes, and skills needed to
implement an ODR that is truly beneficial to the facility.
One petrochemical plant that introduced the SKF ODR realized an
immediate success with the early detection of failing bearings in a
naptha pump motor. Tne motor would have run to failure if the operator
hadn’t detected the problem. The vibration department confirmed the
problem and a spare pump and motor was prepared for installation. A
catastrophic pump failure would have resulted in plant downtime and
employee overtime with a total out-of-budget cost of 15.000 euro.
At another petrochemical plant early life and random bearing failures
were causing unscheduled downtime. After the introduction of an ODR
system a decrease in bearing temperature was detected. The temperature
had dropped 15°F from normal. By having trend data readily available,
the operator was able to identify a change and act. Instant inspection
revealed a coolant leak that would have led to lost production. The
early detection and correction saved the plant 61.000 euro.
Proactive Reliability Maintenance (PRM)
Proactive Reliability Maintenance on the other hand is an asset
efficiency process that enables continuous improvement of maintenance
strategy and machine performance.
Most traditional forms of predictive maintenance will form a sustained
maintenance loop, whereas the Proactive Reliability Maintenance (PRM)
process, developed by SKF, forms a continuous improvement loop. The
following four steps build one upon another to prevent repetitive
failures or problems.
Step 1: Establish a predictive system
The first step is to design a Predictive Maintenance (PdM) system
specifically for the plant, based on information provided by an SKF
assessment which provides an understanding of the parameters that
affect plant and equipment effectiveness. The PdM system includes
activities such as vibration analysis and bearing monitoring,
thermography and lubrication analysis. The PRM process may also
highlight the need for additional activities during maintenance, such as
geometric alignment, precision balancing, lubrication, filtration and
sealing improvement.
Step 2: Diagnostics and root cause analysis
SKF Reliability Systems engineers will diagnose the root cause of
problems and determine corrective maintenance actions, such as machine
realignment, changing the lubricant, or replacing a damaged component.
Detailed machine diagnostics can be conducted on site, or at a remote
diagnostics facility using Condition Monitoring. Physical analysis on
the damaged components may also be required to determine the root cause
of the failure. This information is used to prevent the same type of
failure from recurring.
Step 3: Key Performance Indicators to measure improvement
Key Performance Indicators (KPIs) are performance improvement
targets established jointly between SKF and the customer. They may cover
a wide range of factors, from bearing performance to plant availability.
Where possible, once a KPI is achieved, a new target is set to
facilitate continuous improvement.
Step 4: Operational review process
Periodic review of the improvement program is important to monitor
KPI achievement. Results are documented and presented at performance
review meetings. Operational review meetings are held to continually
refine the PRM process to achieve the best balance of plant asset
performance with the PRM process activity cost.
How the plant will benefit
Implementation of a well managed Proactive Reliability Maintenance
process will ensure the best possible return on plant assets by
managing potential risk. SKF Reliability Systems can guide a company in
establishing its own PRM process—or design, implement and manage the
process for the company. This can apply to the entire plant or any area
of it. A full management program will include all the hardware,
software, and the technical resources needed to ensure measurable
improvements.
PRM case history
At one petrochemical plant consistent fan failures in the process
area resulted in a Mean Time Between Failure (MTBF) measured in months
rather than years. The average repair cost for a fan was 5.725 euro and
production downtime was estimated at 30.500 euro per hour. Introducing
the SKF fan PRM led to the doubling of the MTBF for the critical process
fans . This gave increased plant productivity, and lower costs, with
bottom line savings of 1.900.000 euro. <<
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