Maintenance strategy & cbm basic introduction

TRAINING PROGRAM ON TRAINING PROGRAM ON PREDICTIVE MAINTENANCE PREDICTIVE MAINTENANCE

(CONDITION B(CONDITION BASED MAINTENANCE)ASED MAINTENANCE)

MAINTENANCE STRATEGIES

FOUR MAINTENANCE STRATEGIES

On-Failure (B/D)Fix it when it fails

Fixed TimeMaintain based Upon calendaror running time

Condition BasedMaintain based uponknown condition

Design OutDesign out cause offailure

Maintenance Plan

• Applicable to plant that exhibits wear out - but must be used in conjunction with other strategies

• Only effective if correctly implemented

CONDITION BASED MAINTENANCE (CBM)

• Advantages

Allows shutdown before severedamage occurs

Allows run to failure

Production can be modified toextend unit life

Cause of failure can be analysed

• Advantages

Permits maintenance to be planned

Labour to be organised

Spares to be assembled

Modifications can be planned

CONDITION BASED MAINTENANCE (CBM)

What is Condition Monitoring?

CM depends on the trending of parameters which are indicators of the condition of key equipment failure modes

0

10

20

30

40

50

60

Life Units

0

10

20

30

40

50

60

Life Units

Failure Characteristic

  B < 1

Wear out Random dominated

Early life

Failure Probability graphB > 3

Difficult Expensive

Easy Cheap Difficult Expensive

Easy Cheap

High Low High Low High Low

Condition Monitoring

Mean time between failure

Strategy in order of preference

Fixed – time Operate-to- failureCondition based Design out

Condition- based Fixed-time Operate- to-failure Design- out

Condition based  Operate- to failure

Design- out Condition -based Operate- to failure

Design- out Operate- to failure Condition based

Design-out Condition- based Operate-to failure

Analysis of Maintenance records permits an effective strategy to be chosen

1 < B < 3

HUMAN VS MACHINE

NDT/CBMHUMAN VS MACHINE

SYSTEM

/MONITORING

HUMAN MACHINE / PROCESS

TEMPERATURE FEVER / OTHER HOT SPOT

MECHANICAL ELECTRICAL PROCESS SYSTEM

INTERNAL TESTS PATHOLOGICAL TESTS X- RAYS CT SCAN, MRE ULTRASOUND ANGIOGRAPHY

DEBRIS ANALYSIS OIL QUALITY NDT FLAWS RADIOGRAPHS

EXTERNAL TESTS BLOOD PRESSURE ECG

OVERALL VIBRATION VIBRATION SIGNATURES

NDT/CBMHUMAN VS MACHINE

TYPE OF MAINTENANCE

HUMAN MACHINE / PROCESS

CONDITION BASED MAINTENANCE

MONITORING OF BLOOD PRESSURE CHLOROSTROL LEVEL SUGAR FEVER CANCER CELLS PATHOLOGICAL TESTS ULTRASOUND ANGIOGRAPHY X- RAYS CT SCAN, MRE

VIBRATION MONITORING THERMOGRAPHY QUALITY / DEBRIS

PARTICLES TRENDS THICKNESS / CRACK

MEASUREMENT PERFORMANCE / VISUAL

MONITORING OTHER CBM TECHNIQUES

(CORROSION, AEM ETC)

NDT/CBMHUMAN VS MACHINE

TYPE OF MAINTENANCE

HUMAN MACHINE / PROCESS

PREVENTIVE MAINTENANCE

PREVENTIVE REMEDIAL MEASURES / CARE AS PER CBM MONITORING DIET CONTROL WEIGHT MONITORING MEDICINE MEASURES CHECKS AT REGULAR

INTERVAL ADVANCED TESTS –

ECG / SCANS

CHECKS / MEASURES

AGAINST DETERIORATION PREPARATION OF S/D AS

PER MONITORING CONTROL ON DEBRIS BY

FILTRATION VIBRATION CONTROL BY

ALIGNMENT, BALANCE PM /PI SCHEDULE AS PER

EQUIPMENT COMPONENT

LIFE / DETERIORATION

TRENDS

NDT/CBMHUMAN VS MACHINE

TYPE OF MAINTENANCE

HUMAN MACHINE / PROCESS

BREAKDOWN MAINTENANCE

(WITH OUT ANY CARE)

HEART ATTACK /

BY - PASS SURGERY INSULINE DROPS –

UNCONSCIOUS KIDNEY PROBLEM CRONIC TYPHOID TUMOUR / ULCER

BEARING SEIZED SYSTEM BREAKDOWN

DUE TO PROCESS/

MECHANICAL /

ELECTRICAL FAILURES PANEL BURNOUT

CONDITION BASED CONDITION BASED MAINTENANCE MAINTENANCE

TECHNIQUESTECHNIQUES

Human SensesVISUAL MONITORING

Touch Sight Smell Hearing

The simplest techniques are often the best - but to be effective any evaluation must be quantifiable

Thermal Techniques

Contact Sensors

(Cheap but have limitations) PaintsThermocouplesLiquid expansion

Infra-red Cameras & Videos

(Expensive but very powerful)

Thermal Techniques

Applications : Pipe work

Insulation breakdownleaks

Electrical High resistance jointsOverheating componentsHot motors /Blocked cooling filters

MechanicalBearingsCoolant Gear Box etc.

Vibration MonitoringVersatile tool for condition monitoring of

rotating & reciprocating plant

Wide range of techniques and instrumentations

Careful selection and application of technique is essential for success

Vibration Monitoring: Techniques

Overall Acceleration, Velocity & Displacement

Vibration Spectral Monitoring

Run-up/down tests

Phase plots

Time Signature Analysis

Vibration Monitoring:Rolling Element Bearing MonitoringRolling Element Bearing Monitoring

Spike Energy/HFD High Frequency Velocity Overall Acceleration Shock Pulse

Performance MonitoringInvolves the use of existing data,

Current Temp Pressure Flow rate

Performance MonitoringAny variable which is indicative of a failure mode

Thermal efficiencyWear rateCompressor loading / unloading timeProduct Accuracy

Wear Debris Monitoring Techniques

Spectrographic Oil Analysis (SOA)

Ferrography (direct & analytical)

Particle QuantifierMicroscopic optical assessment

Choice of technique is critical to success

Non Destructive Testing Ultrasonic Methods Radiography Dye Penetrant Magnetic Particle

Corrosion Monitoring Visual Inspection Ultrasonic Leak Detection Coupons Electrical Resistance Probe

CRITERIA FOR SELECTION OF CBM TECHNIQUE

CBM TECHNIQUE TYPE OF EQUIPMENTVIBRATION ANALYSIS All Rotating Equipment - Fans, SPM Compressors, Pumps, high LASER ALIGNMENT speed Gear boxes, Motors etc.

THERMOGRAPHY & All Electrical PCC, MCC, THERMAL IMAGING High Tension Switch yards Motors, Mech. Drives etc. NDT THICKNESS/ FLAW All type of Tubes, Pipes & DETECTION Vessels, Plates, Shaft etc.LUBRICANT & WEAR All Type of Lubricating &

DEBRIS MONITORING Hydraulic OilsDISSOLVED GAS All Transformer OilsANALYSIS

EQUIPMENT CAUSES OF FAILURE

TECHNIQUES COMMENTS

Fan Out of balance Misalignment Bearing

damage Aerodynamic

forces Belt problems

Overall acceleration Spike energy

measurement Overall vibration Vibration analysis Flow measurement Motor current

measurement

Simple application using windowed spectra to trend deterioration in specific faults.

Equipment performance is monitored by measuring process parameters

SAMPLE APPLICATION OF MONITORING TECHNIQUES

EQUIPMENT CAUSES OF FAILURE

TECHNIQUES COMMENTS

Pumps Misalignment Bearing

damage Cavitation Impeller

damage Hydraulic

forces

Overall vibration Vibration analysis Overall acceleration Spike energy

measurement Flow measurement Motor current

measurement

Windowed spectra to trend deterioration in specific failure modes. Cavitation can be detected using frequency analysis. Often blade pass frequency indicates hydraulic problems

SAMPLE APPLICATION OF MONITORING TECHNIQUES

Identify Equipment & CBM Technique

Schedule & Planning Measurement

Unscheduled JobsScheduled Jobs

Data Entry

Analysis Abnormal Reading Normal Reading

Exception Report for Corrective Action Report Generation

Corrective Action by DEPT.

.

Abnormal Reading

Feedback from DEPT. Re Measurement Normal

Reading

Trend for History

and Analysis

Re circulation of Report

FUNCTION AND FLOW OF CBM SYSTEM

VIBRATION INSTRUMENTS

IRD Model - 306 M

Model PL-31 ANALYZER SPM A 30

INFRARED THERMOMETERSCONTACT THERMOMETERS

THERMAL IMAGER Model IRISYS

THERMOGRAPHY INSTRUMENTS

LUBRICANT OIL TESTING

WEAR DEBRIS /PARTICLE ANALYSIS - SEPARATE INFRASTRUCTRUE /LAB

ULTRASONIC THICKNESS GAUGE make - MODSONIC

ULTRASONIC FLAW DETECTECTORS

ULTRASONIC FLAW DETECTOR MODEL GAILLILO-100

Condition Based MaintenancePump Vibration Measurement Non contact temperature Measurement

Thermography of switch Yard Wear debris analysis ( External)