Reducing downtime by ensuring accurate Maintenance,
Reliability and Inspection planning
SMC
Maintenance Management
Why maintenance management ?.......
Effective maintenance management is critical to the operation of the plant equipment.
to keep the machines/equipment in their optimum operating conditions
helps in maintaining and improving the operational efficiency of the plant facilities
Key objectives of maintenance management
to ensure that equipment and assets are always in good condition
To extend the useful life of the plant, machinery and other facilities by minimizing their wear and
tear
to carry out prompt emergency repair of equipment so as to secure the best possible availability
for production
To minimize the total maintenance cost which includes cost of repairs, cost of preventive
maintenance and inventory costs associated with spare parts/materials required for
maintenance
To improve reliability, availability and maintainability
Efficient use of maintenance equipment’s and personnel
Maintenance strategies
Taking into consideration various concepts of programs, managers may plan and undertake maintenance
activities proactively or reactively
Key maintenance strategies followed by best practice industries
(a) Corrective or breakdown maintenance
Done after the equipment is out of order and no longer able to perform its normal function
(b) Preventive or time based maintenance
Periodic inspection/minor repairs on equipment at predetermined intervals based on calendar days or running
hours, to reduce any unexpected breakdown
(c) Predictive maintenance
Predictive maintenance (PdM) uses condition-based monitoring technologies to detect and eliminate
equipment failures. It involves monitoring for evidence of changed conditions within the equipment
(d) Proactive maintenance
This have primary emphasis on tracking all failures to their root cause. Each failure is analyzed and proactive
measures are taken to avoid the repetition of the similar failure
It’s key elements are
Identify the Root Causes of Machine Failure
Resolve Problems Before They Become Failures
Extend the Life of Machinery and Reduce Downtime as a Result of Machine Failure
Maintenance planning
Maintenance planning objectives
Effective utilization of the maintenance workforce by reducing delays and interruptions
Reduced maintenance cost.
Maintaining the operating equipment to perform its intended function as and when required
Benefits of Maintenance planning
Increased productivity
Reduced equipment downtime
Increased equipment life
Lower spare parts inventory and usage
More work with fewer resources
Less Maintenance rework
Role of reliability in Maintenance planning
Prepare and/or review the maintenance strategies on equipment and recommend the best suitable one
Prepare and/or review the PM tasks on each equipment and optimize the tasks
Evaluate the SAP data input and equipment history and recommend any improvements if required
Provide assistance/guidance in spare parts optimization
ASSET INTEGRITY STUDY
No of plant S/D & Production loss
5
5
4
Reasons for Shutdown / Production loss
Planned
shutdow
n / TA; 1
4
Electrical ; 1
TBC; 1
Rotary
maintenance
;1
3
Instrument
malfunction;
7
Operational ;
2
1
Year
2010
Year
2011
Year
2012
Year
2013
Year
2014
Equpt /
Piping
failures; 9
Year
2015
Plant shutdowns and equipment failures were reviewed, in addition to other industry
failures from MARSH industry failure cast studies.
To strengthen the barrier
Typical bath tube curve of plant equipments
Reliability Vs Availability
Understanding the Difference Between Reliability and Availability
People often confuse reliability and availability.
Simply put availability is a measure of the % of time the equipment is in an operable state while
reliability is a measure of how long the item performs its intended function. We can refine these
definitions by considering the desired performance standards.
A piece of equipment can be available but not reliable. For example the machine is down 6
minutes every hour. This translates into an availability of 90% but a reliability of less than 1 hour.
Generally speaking a reliable machine has high availability but an available machine may or
may not be very reliable.
Availability vs Reliability
Availability
Definition
The percentage of time
that something operates
normally over a period of
time.
Reliability
Long term operational performance
in real world conditions.
RBI and RCM
RBI
RBI itself is the proactive approach to identify the risk and area need more attention.
RBI during commissioning will add value in terms of
Any modification required can be easy done before plant start up to reduce risk.
Any additional inspection required can be done to reduce the hidden risk.
Risk rank and prioritization will be more accurate with available thickness data.
RCM
Will help to identify the components whose potential failures lead unwanted/unexpected outage of the
plant.
Identify the causes of failures and select appropriate maintenance strategy.
This will help to optimize most cost effective/appropriate maintenance task to ensure the integrity of the
asset.
Reliability Planning
RBI:
SMC following RBI methodology for inspection and major RBI requirements are set with Turnaround since most of the
equipment requires shutdown for inspection.
After each TA new risk matrix will be published and inspection planning will be done based on RBI.
Inspection History:
Inspection history is most important
Ensure all the predictions are clarified during available opportunity to plan corrective action during TA
Detailed report on finding
Online/Offline vibration monitoring:
System1 online monitoring , off line monitoring and performance parameters.
vendor recommendation.
Lube oil analysis: Routine and specialized lube oil analysis.
Similar industry experience:
Collect experience from similar industries time to time.
SMC will participate TA in similar industries.
Published papers (challenges against code)
Information from vendor/ licensers
Operational history:
Information from Operation history
Process Changes during normal operation and upset (will change extent of inspection)
Inspection and condition monitoring
International code/ local regulatory/ vendor recommendation/ best practices are influencing
planning.
Change in frequency of monitoring based on the equipment current condition will assist in early
prediction and proper outage planning.
Immediate feed back on observation will prevent unwarranted failures or any secondary damages.
Earlier prediction of equipment condition will help in proper resource planning and reduce
maintenance/ production loss.
Early identification of anomalies will help to have more intensive analysis thereby predicting the root
cause and subsequent outage plan.
After every startup / upset in plant inspection engineer should collect all changes in operation
parameters and analyze.
Base line data
One of the important proactive approach is collection of base line data
Base line data on static equipment during construction – easy/ less cost/ accurate RBI
Base line data on rotating equipment – Effective trending/estimating the potential failure/planned
outage rather than unplanned of run to failure
Base line data for rotating equipment collected during commissioning using offline vibration and
temperature monitoring
SMC base line data captured during hydro test package and equipment acceptance
Critical items inspection done before commissioning in SMC
Eg: Reformer tube eddy current testing and creep measurement done before commissioning.
Operating parameter changes to be captured by inspection engineer
12
Inspection engineer role:
Inspection engineer required a through knowledge on operation of their plant equipment.
Any change in operating parameters to be addressed to inspection engineers (Pi system
available in most of the plant).
Possibilities of crossing design boundary is high during startup.
After every startup / upset in plant inspection engineer should collect all changes in operation
parameters and analyze.
check to be done for any differential thermal expansion occurred and bellow provided is
sufficient to accommodate this expansion.
Simple way to check mean metal temperature is
For the shell, take the average of the inlet and outlet temperatures. As the tubes experience
the shell side and tube side fluids, the mean temperature can be taken as the mean of the
four terminal temperatures.
This method can be used if you have no other way of accurately getting the mean metal
temperatures.
Periodically collect the lab analysis for hot and cold media to check any corrosive media
entered or crosses the limit.
Process Control
Technical guidance to production team to operate the plant with in the design envelop.
Change in process parameter to be discussed and recorded
Detailed study on process changes in terms of what can go wrong
Information to inspection engineer to concentrate specific problems in specific area.
Laboratory: continuous monitoring of feed stock / intimidate stream to remain with in the design
limits.
Equipment preservation
Intermittent service equipment preservation
Raw material and spares
Routine inspection of Critical equipment rotors and evaluate the condition of preservation
Extensive Corrosion survey and painting campaign
Bad actors
Identifying bad actors is one of the most important task in ensuring the plant integrity
This provides early warning on recurring failures which warrants for an appropriate RCA to identify
the root cause of the failure
Identifying the root cause and consequent corrective action significantly reduces the unplanned
outage and maintenance cost
Ensures availability of the equipment
METHANOL CATCH POT – Prediction of damage
Example of Operation input to predict type of damage
•
•
•
Wax deposition observed in one of the strainer and suspected demister damage in catch pot.
With this information repair activity plant will required material and resource in advance.
During TA damage in demister was observed, lifting of few sections and deformation of the support beam
observed.
Damaged demister
Restored Demister & Supports
Q&A