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    Case Study on Additive Manufacturing Metallic and Non-Metallic Pump Impellers for Corrosive Application
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2024-02-27) Chew, Grace; Asokan, Kaushik
    At one of our customer/end-user chemical plants in Singapore, they had a problem with frequent replacement of the Hastelloy C impellars casted used in their centrifugal pumps in service with Sodium Hypochlorite application. The existing impeller were always noticed with severe pitting corrosion damage and often required a quick turnaround to replace the parts back to service.
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    CS18: Morton Effect with Pedestal Support Influence
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Li, Wei; Hatori, Hiroki; Wang, Qingyu; Pettinato, Brian
    The Morton effect was encountered during a compressor rotor high speedbalance Morton effect for high speed balance configuration was not consideredin the design phase analysis, and it was a unique experience The high speedbalance pedestal stiffness will be shown to have a significant influence on theMorton effect This presentation will cover:(1) Design phase screening & analysis of this case(2) High speed balance & test floor Morton effect mitigation(3) Morton effect analysis & root cause analysis(4) Conclusions
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    CS17: Torsional vibration problem with recirculation gas blower due to variable frequency drive
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Kanchana, Pongphop; Kuramoto, Khattiya; Mukdaburapha, Supakorn; Lekmanee, Pattamon
    The centrifugal blower equipped with variable-frequency-drive (VFD) motor services in petrochemicalplant The unit was experienced many times of coupling failures after replacement new VFD,metallurgical study indicated torsional fatigue crack Supported by API 684, the VFD has beensuspected of the torsional excitation source Consequently, the torsional vibration was measured inthis study interacted with VFD characteristic The results showed operating with Direct Torque ControlMode, the oscillating torque increased dramatically due to closed-loop control interaction, to maintainthe speed of motor precisely by adjusting the internal torque reference Proper tune of speedcontroller parameters minimize oscillating torque less than five times Also, switching control mode toscalar mode, without closed-loop interaction, the torsional excitation was greatly reducedAs a result, it is decided to configure VFD operating in scalar mode control and compare the actualtorque was evaluated to the limited torque which coupling manufacturer recommended
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    CS15: Centrifugal Pump Upgrade for New Operating Condition
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) MUTHANANDAN, SUNDRALINGAM; B YAHYA, M FARID
    Centrifugal Pumps used at Upstream and Downstream facility are critical for Oil & Gas business However, the pump process requirement may change over time due to depleting reservoir in Upstream or new process requirement in the downstream facility This may require pump modification to suit for new operating condition In one of the facility in PETRONAS, a major revamp has taken place due to new operating condition This had resulted into design modification of the pump by increasing the pump impeller diameter Various issue were encountered during execution such as installation of the new rotor into the casing and high vibration during commissioning Upon investigation, it was found that the main reason for the problem was due to the size of impeller diameter against volute diameter which also determine impeller radial clearance
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    TB20: On The Experimental Static and Dynamic Load Performance of a Water Lubricated Hybrid Thrust Bearing
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) San Andres , Luis; Yang, Jing; Wilkinson, Scott
    Fluid film thrust bearings (TBs) carry axial loads and control the position of rotating machinery thus enabling tight clearances forthe efficient aerodynamic operation of impellers in pumps and compressors Prediction of thrust forces is largely empirical, emphasizingthe need to test TBs for use in reliable rotating machinery equipment This paper presents a water lubricated test rig housing a pair ofhydrostatic TBs and describes the experimental quantification of their static and dynamic forced performance The test rig comprises ofa drive motor, a coupling and quill shaft, and a rigid rotor with two end collars facing the TB elements Water lubricated radial bearingssupport the test rotor One slave TB rigidly attaches to the rig casing while the test TB connects to a load shaft supported on aerostaticbearings The TBs, each with ID = 406 mm and OD = 762 mm, have eight pockets, 20° in arc length and 81 mm in radial length, withdepth and feed orifice diameter equal to 051 mm and 180 mm for the test TB, and 044 mm and 155 mm for the slave TB, respectively Copyright© 2020 by Turbomachinery Laboratory, Texas A&M Engineering Experiment Station 2During operation, while the rotor spins to a maximum speed of 6 krpm (TB OD surface speed = 24 m/s), cold water at a maximumsupply pressure (Ps) of 483 bar(g) lubricates the TBs A calibrated taut string mechanism applies a static load (W) on the movable shaftand which pushes the test TB against one end of the rotor collar The rotor in turns transmits the same static load onto the slave TB Fordynamic load tests, a calibrated gun delivers impacts onto the load shaft and which excites both TBs and the rotor The measurementsinclude rotor axial displacements, load shaft acceleration, and the applied loads, static and dynamic Form these measurements, amechanical system model aids to estimate the TB force coefficients; namely, stiffness (Kz), damping (Cz), and added mass (Mz) Fortests with a constant axial load (W), the axial clearance (Co) increases as the TB lubricant supply pressure (Ps) increases Under a constantwater supply pressure (Ps) into the bearings, the test TB clearance (Co) decreases as the applied specific axial load (W) increases to amaximum of 16 bar The measured static load performance, agreeing with predictions as well as with earlier test results, demonstratesthe TBs operate mainly as hydrostatic ones since hydrodynamic features derived from surface speed are small Form the multiple impacttests, for the TBs operating with a fixed supply pressure, the test TB experimental stiffness (Kz) and damping (Cz) increase as W increases,meanwhile the added mass (Mz) varies slightly Operation with a constant W and with an increase in water Ps yields an increase in Kzand Cz without a change of its added mass Predictions agree well with the experimentally derived force coefficients The test results arerelevant to the pump industry, in particular for vertical lift processes
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    CS07: Dry Screw Compressor Trip on Axial Displacement during Cold Start
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Kuppa, Sridhar; Baer, Heinrich
    Dry Screw Compressor experienced HH axial displacement trip within 15 minutes after every cold start-upsince the MMS system upgrade in 2016• Failed attempt to successfully restart this compressor after every planned maintenance activity has causeddisruption to Operations Process planning• Trip recurrence data indicated rotor thermal growth beyond trip limits Once the compressor trips, the axialprobe position needs to be adjusted to allow a successful re-start of the compressor• Further analysis of rotor thermal growth ascertained that during the first few minutes the effect of rotorthermal expansion was more dominant than that of the gearbox casing, which only occurred about twohours later• Correlation between the trip recurrence and the compressor thrust bearing type (fixed pad) was alsoevaluated as part of the investigation• Wear allowance of the thrust bearing and the rotor to casing clearance were evaluated in order to determinethe trip effects to the overall train integrity• Reevaluation of the protection mechanism of the machine was done and changes made to remove the tripon axial• This case study presents details of the problems, background and the engineering assessment to achieveviable and fit-for-purpose solution
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    CS09: Investigation and Resolution of Frequent Pulsation Dampener Bladder Failures of Condensate Export Reciprocating Diaphragm Pumps Causing High Vibration and Loss of Primary Containment
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Bin Mohd Zahari, Ir. Mohd Zakiyuddin; Swee Miin, Chin
    Unusual and repeated bladder ruptures of pulsation dampeners installed on two units ofCondensate Export Triplex Double Diaphragm Reciprocating Pumps and two units of GlycolCirculation Triplex Plunger Pumps had caused a platform in Malaysia Offshore sufferedfrom frequent unplanned production shutdown and loss of millions of Ringgit sincecommissioning These frequent dampener bladder ruptures started by causing excessivevibration and the situation was worsened due to unavailability of enough sparedampeners Without proper dampening of pulsation, HSE issue had also became a seriousconcern due to loss of primary containment (LOPC) from the leakage of broken pipingjointThis case study discusses how the problem was found to be caused by a combination ofseveral factors and was solved by utilizing root cause failure analysis and step-by-stepmitigations
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    TB19: Mechanical Validation of Axial Impellers with Plastic Blades in Genset Applications
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Geiger, Nicolas
    Hybrid axial impellers with a hub made of aluminum and blades of engineering plastics are commonly used as part of cooling packagesfor industrial applications The use of plastics opens for a larger design flexibility in terms of blade shapes, allowing optimized profilesfor higher efficiency, lower noise and/or higher pressure depending on the application requirements Additionally, the component weightand cost are lower than their fully metallic counterparts In environments where spark ignition is not permitted (ATEX), the use ofantistatic, reinforced plastics is mandated in some casesHowever, due to lower stiffness of the blades, their natural frequencies are lower than a metal impeller of the same size, but with higherdamping Therefore, special attention must be put into validating the impeller for the application, in order to avoid resonance withvibration inputs coming from the engine and/or from aerodynamic interaction with the shroud and eventual obstacles in the airflowThis article describes the mechanical loads and vibration issues typically encountered in genset applications, as well as the tools usedfor validation, using numerical simulation as well as physical tests in the machine
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    TB18: Air Cooled Condenser Fan Blade Failure
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Li, Cindy; Smith, Patrick
    A surface condenser is a commonly used term for a watercooled shell and tube heat exchanger installed to condenseexhaust steam from a steam turbine These condensers areheat exchangers which convert steam from its gaseous state toits liquid state at a pressure below atmospheric pressure➢ Where cooling water is in short supply, an air-cooled condenser(ACC) is often used An air-cooled condenser is however,significantly more expensive and cannot achieve as low a steamturbine exhaust pressure (and temperature) as a water-cooledsurface condenser➢ Configuration of an ACC consists of:• Steam duct• Condensing tube bundles and headers• Fans and gearboxes• Wind wall and steel structure• Water wash system• Etc
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    TB14: A Practical Data-Driven Analysis Case Studies for Gas Turbine Operators
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Ahmad Asnawi, Khairul Fata b; Omar, Azreel Zairee b
    There is abundance of machinery performance data available nowadays due to recent development ofsensors and computational powerUsually those data left to complex/ advance tools (special software) and technique (AI, MachineLearning) for analysisHowever, operator also should be able to practically manipulate and analyze those data to come-outwith useful information to help decision processThis presentation elaborate how to perform data driven analysis on available data with existing tooland knowledge
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    TB11: PETRONAS Rotating Equipment Analytics (PROTEAN): Disrupting and Challenging the Status Quo of Digital Remote Monitoring Solutions
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Abd Rahman Sabri, Ir Dr Harris; Swee Min, Chin
    In this paper, the author will describe how PETRONAS Carigali Sdn Bhd started to embark on their journey in developing their ownin-house digital solution for rotating equipment remote monitoring system for the supercritical turbomachinery equipment for offshoreplatforms Instead of the traditional way of relying heavily on Original Equipment Manufacturer’s (OEM) remote monitoringsolutions, the status quo has been challenged and resulted in astronomical replication from the pilot project of two (2) units tocurrently covering 126 units within three years of PROTEAN operationalization PROTEAN was also recognized by the industry bywinning the Institute of Engineering and Technology (IET) Malaysia Industry Excellence Gold Award 2019 due to its contributiontowards the advancement of science, engineering & technology impacting human, environment, social needs, and economy inMalaysia
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    TB12: Rotating Machinery Reliability & Performance Enhancement Through Digitalization And Internal Capability Building
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Sayed Ghazali, Ir. Syed Afdhal
    Petronas Carigali Peninsular Malaysia Asset (PMA) is currently operating more than 80 units of gasturbine comprises or Power Generation and Gas Compression system More than half of a gas turbinepopulation in PETRONAS resides in PMA It is a great challenge to Operate and Maintain these turbinesto achieve its intended reliability and performance To fulfil PETRONAS Corporate agenda ondigitalization, PMA has embarked on Machinery Remote Monitoring & Diagnostic (MRMD) A fullfledge MRMD Center has been established in PMA to monitor the performance and operations ofidentified Super Critical equipment The setup has significantly reduced equipment downtime andunplanned deferment with value creations and cost avoidance for more than RM5 million a year Onthe other hands, PMA has a dedicated team called ‘Roving Gang’ who maintain turbomachineryequipment in PMA operations PMA has institutionalized internal capability building and competencywhich resulted in reduction of vendor Field Service Representative (FSR) utilization to more than 500%within 4 years This paper shall elaborate the best practices and ways to achieve World ClassMaintenance Practitioner which resulted in good Reliability and Performance of rotating equipmentbased on a case study in Petronas Carigali Sdn Bhd
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    TB08: How the Application of Turboexpanders with Variable Inlet Guide Vanes Supports Increased Flexibility in LNG and LPG Production
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Agahi, Reza; Harman, Rob; Duck, Cory
    Radial inflow turbines (RIT), or turboexpanders, have become essential to the entire oil and gas industry, but also to specific applications in the realm of Liquefied Natural Gas (LNG) and Liquefied Petroleum Gas (LPG) The RIT’s unique feature – the variable inlet guide vanes (vIGV) – renders the turboexpander as a variable geometry turbomachine, making it a viable and effective solution for variable load and flexible LNG production In the specific context of one case study – a mini-LNG plant in the United States – the authors discuss these characteristics of the RIT, while also describing its impact on plant efficiency, and generating monetary advantages for the operators
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    TB02: Assessing compression methods for increased reliability, flexibility and efficiency in gas processing plants
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Patel, Tushar; Tabaza, Sami
    Many of today’s gas processing plant operators face varying and often uncertainconditions This includes challenges such as the mode of operation and feed gasuncertainty For instance, gas processing plants can receive both rich and leangas Therefore, the plants must have the flexibility to handle both types withoutreducing performance Similarly, plants require the agility to operate in ethanerecovery or ethane rejection modes, respectively, and are often required to operatein extreme ambient temperature conditions Thirdly, regardless of the conditionsand mode of operation requirements, overall reliability is of essential value Thesecircumstances place substantial requirements toward the compressor technologyas far as reliability, flexibility and efficiency is concernedThis case study of a gas processing plant in North Dakota (USA) will examine theuse of a mechanical refrigeration cycle using commercial-grade propaneDiscussing different compressor technologies available for such applications, theauthor will analyze the performance characteristics of integrally gearedcompressor technology when applied in gas processing plants
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    CS06: Inappropriate Operation During Mechanical Running Test of a High-Pressure Compressor Equipped With an Hole Pattern Seal
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Bidaut, Yves
     During the mechanical running test of a HP centrifugal compressor, the rotorexperienced a sudden increase of the radial vibrations During run-down thecompressor experienced a trip and high vibrations were recorded The RCA revealed: for the manufactured clearance of the hole pattern seal thetemperature level and the gradient of the pressure and temperature during the startup was too high A new hole pattern seal sleeve was manufactured with increased clearances Theduration of the start-up was increased in order to decrease the temperature gradientAfter reassembly no high vibration appeared anymore Generally: Operation during the mechanical test (especially at trip speed) requirescareful attention if high discharge gas temperature is expected
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    T14: Dry Gas Seal Contamination And Solutions To Increase Seal Reliability
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Tuffentsammer, Martin; Hopfner, Thomas
    Recent incident reports and studies indicate that dry gas seals are responsible for only 39% of compressor shut downs and are themost reliable sealing solution However, if the dry gas seal fails the costs can be very high and the availability of the whole plantmight be constrained The major causes of dry gas seal failure can be clustered in four different incidents from which three are relatedto contamination Process gas contamination Seal gas supply contamination Bearing/Lube oil contaminationThe seal gas line of the dry gas seal supply system is designed and manufactured to supply clean and dry gas to the dry gas sealNevertheless, the originally designed filters and treatment components of the supply system may no longer fit to the current operatingconditions of the machine anymore as gas composition, temperature or pressure requirements are changing over time As well duringupset or transient operating conditions, the functionality of the supply system might be limited Upgrading the supply system to cope with the current process requirements is often a difficult venture, which requires the involvement of various parties Enabling the sealinstead to cope with difficult environments can be a first solution to ensure the availability of the plantThis paper will contain information on the following topics: Different types of contamination Dry gas seal failure mode due to contamination Solutions to increase seal reliability How to tackle process gas contamination Design features to handle seal gas supply contamination Avoid/handle bearing/lube oil contamination
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    T15: Numerical Simulation and Validation of Motor Dynamics in Reciprocating Compressor Driveline Coupled with Stiff and Soft Elastic Couplings under Continuous and Transient Operating Conditions
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Hasasn, Mahamudul; Naumann, Marcel
    Reciprocating compressor is often used in the field of gas compression industry and generates harmonic torque excitation in adriveline The objective of this paper is to simulate the dynamic torsional vibrations by considering motor as an electromechanicalsystem with real electrical characteristics and solve them numerically in order to capture the accurate torque oscillations insidecouplings The wrong selection of coupling may lead to the damage of the coupling as well as the components connected in thedriveline as they produce high level of vibrations A large deviation of torque fluctuations has been observed with two differentapproaches between simple model as spring damper and multiphysics motor model The accuracy can be achieved with a user definedelectromechanical motor model and the negative damping effect is accomplished without tuning the model Finally, the simulationresults were compared with measured experimental data The validation shows a good match The final models are based on validationconcept Two examples are presented with flexible and torsional stiff couplings in order to optimize the coupling for a higher systemreliability in a particular driveline The flexible coupling shows relatively low vibratory torque in the coupling compared to torsionalstiff coupling The damping and dynamic stiffness of rubber couplings play an important role to attenuate vibration as the couplingmode shape controls the vibration signature Moreover, the transient loading under short circuit event and energy saving valve unloaders operating conditions haven been investigated that are used in many reciprocating compressors applications
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    T10: Strategies to Prevent Sudden Catastrophic Compressor Failures during Transient Operating Conditions
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Smith, Patrick
    Many compressor failures occur during transient operating conditions These failures can be prevented or minimized by having agood machinery condition monitoring program, a good machinery protection system and good maintenance practices The purpose ofa machinery condition monitoring system is to identify machine degradation early so that action can be taken before it progresses to apoint of machine failure The purpose of a machinery protection system is to ensure that a machine is operated within its normalparameters, provide detection of an imminent problem, and to trip a machine if there is a serious problem A machinery protectionsystem consists of the instruments that measure the key parameters, and a control system that displays, alarms and/or trips the machineif a parameter exceeds predefined limitsMachinery protection systems can increase machinery reliability by mitigating damage to the machine when a problem developsHowever, the scope and complexity of machinery protection systems, even for similar pieces of equipment, can vary quite a bitWhile more sophisticated machinery protection systems can further improve reliability, the additional instruments and controlsincrease cost, can result in additional operating complexity if there are more constraints to control, and can lower machine availabilityby causing unnecessary trips Thus, standard, less critical compressors in a simple service may have a very simple protection system,while highly engineered, very critical compressors in a complex service may have a more sophisticated protection systemCondition monitoring can also be a very powerful tool in preventing sudden, catastrophic compressor failures Sometimes the signs ofprogressive damage are very subtle and difficult to detect In these cases, a machine may appear to suddenly fail without warningHowever, a robust condition monitoring system that detects thermodynamic and/or mechanical degradation at an early stage can allowfor action to be taken before the condition worsens to a point that causes a machine failureIn this tutorial four case studies will be presented Each case study will describe a different compressor failure that occurred during atransient operating condition And in each case, it will be described how simple changes in machinery condition monitoring,machinery protection and/or maintenance strategies could have prevented the failure The purpose of this tutorial is to describe howthese strategies can be applied to other compressors to prevent failures or minimize damage if a problem occurs, without addingsignificant cost or complexity, or causing nuisance trips
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    T13: Performance of Industrial Gas Turbines
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Kurz, Rainer; Brun, Klaus; Winkelmann, Bernhard
    Industrial gas turbines have performance characteristics that distinctly depend on ambient and operating conditions Application of these gas turbines, as well as the control and condition monitoring, require to consider the influence of site elevation, ambient temperature and relative humidity, the speed of the driven equipment, the fuel, and the load conditions The reasons for these performance characteristics can be explained by the behavior the gas turbine components and their interaction The tutorial explains the performance characteristics based on the performance of the engine compressor, the combustor and the turbine section, and certain control strategies It introduces fundamental concepts that help to understand the flow of energy between the components Further discussed are control concepts, both for single shaft and two shaft machines, driving generators, compressors, or pumps Methods are introduced that allow to use performance data for trending and comparison purposes The impact of component degradation on individual component performance, as well as overall engine performance is discussed, together with strategies to reduce the impact of degradation
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    T12: Prudent Design for Transient Torsional Vibration in Mechanical Drives
    (Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2021) Bhattacharya, Mantosh
    In addition to the conventional analysis to identify system torsional natural frequencies for rotating machinery train, there may be arequirement to perform transient analysis if the system will be exposed to transient torsional excitation, as identified A transienttorsional vibration of machinery train installed at site may go undetected until a certain number of events occur after which a low cyclefatigue failure could occur Some of the transient events are not possible to avoid such as the start of synchronous motor Meeting themachine design criteria to sustain high oscillating torque during transient events is difficult in terms of cost and effortFrom mechanical design perspective, paper emphasizes that based on frequency of occurrence of transients such as short circuitevents, what prudent action can be taken to protect main driveline To minimize the torsional oscillations startup of synchronousmotor driven train, driven inertia can be kept lower as much as possible by avoiding overdesign of the gear boxes and rotatingmachines to maintain high stiffness Pros and cons of using elastomeric type damper couplings, fluid couplings are also discussed astool to mitigate the high torsional oscillations during transient conditions such as startupWith published API guidelines and API recommended practices, the paper addresses when and how to tackle the design challenges ofrotating machinery -mechanical drive train With latest advent on power electronics, usage of various online protection and monitoringtools such as IGBT (insulated-gate bipolar transistor), partial discharge and flux monitoring system etc which may mitigate theoccurrence of short circuit events to high extent