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
