predictive maintenance for rotating machineries

Predictive Maintenance untuk Mesin-mesin Rotasi

Predictive Maintenance (PdM)

! Langkah-langkah Penerapan PdM

! Teknologi Pendukung PdM

! Case Studies

! Keuntungan Penerapan PdM

Langkah-langkah Penerapan PdM

! Database setup! Pengambilan data di lapangan! Analisis data! Diagnosis permasalahan! Penilaian kondisi mesin! Corrective Action : Balancing & Alignment! Performance Improvement

Vibration

Tribology

IR-Thermography

On-line Monitoring

Motor Current

CorrectiveBalancing & Alignment

Predictive Technology

Vibration Analysis

Vibration Sensor

Data Collector

Vibration Analysis

SOURCE OF PROBLEM

SEVERITY

Vibration Analysis

Machinery Vibration Diagnostic

Tribology – Oil Analysis

Wear

Contamination Chemistry

Extreme

Bad

Marginal

Fair

Good

ABRAS WEAR - Abrasive Wear ExampleP3 - Mobil DTE hydraulic fluidSample Date: 21-FEB-93

Wear - Bad Contamination - Extreme Chemistry - Good

Bad seal leaking coolant into hydraulicsSaw abrasive wear particles on grid 100x

Check - Viscosity, Breather, Contamination, Shop Mic, MechanicalAction - Remove Contaminants (water?) Estimated total water content 2.5089%In Solution 1% +Emulsified 72% +Free 27% = 100%

Infrared Thermography

33.2

19.3

Diff. 1 13.9

*>33.0°C

*<11.4°C

12.0

14.0

16.0

18.0

20.0

22.0

24.0

26.0

28.0

30.0

32.0

Infrared Picture

Photo Visual

Spot 1 78.8

Spot 2 73.0

Spot 3 75.0

*>81.6°C

*<-6.6°C

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0This hot spot proves not enough coolingfrom the fan.

Hot spot reveal thesource of heat from the motor winding.

Note : 1.Average ampere of the motor = 112 A

2. Full load Ampere = 132 A

Spot 1 = 78.8 ºCSpot 2 = 73.0 ºCSpot 3 = 75.0 ºC

Courtesy of VICO Indonesia

Motor Analysis

! Vibration Analysis " Mechanical faults

! Untuk mendeteksi electrical faults– Shaft Current / Voltage– Electric Current Analysis– Temperature

Electric Current Analysis

Shaft Voltage Measurement

Fluting with Spalling

Pengukuran Temperatur

TBI TSI TSC

TSO TBO TTH TCP

TAF

Electrical Faults

! Stator Eccentricity, Shorten Laminations or Loose Iron

! Uneven (variable) Air Gap! Eccentric Rotor! Broken / Cracked Rotor Bars or Shorting Rings! Bad / Loose Connection Rotor Bars/Shorting

Rings! Shorted Rotor Laminations

Corrective Action - Balancing & Precision Alignment

Two Plane

Large/OverhungRotors or Rolls

Multi-Plane

ComplexEquipment

One Plane

Simple Rotors

Corrective Action - Balancing & Precision Alignment

Contoh Penerapan Multi-Teknologi

The Alignment parameter band(2 X RPM) was chosen to trend over time. A forecast of when the fault level would be exceeded with the current trending of values is also applied.

Nspectr automated fault diagnostics was run on the spectrum and it came up with the Shaft misalignment at the coupling as the most probable fault.

2 x RPMVibration Analysis was requested to provide more insight

Thermography indicated misalignment

Excessive heat at the couplingExcessive heat at the bearing from increased load.

Alignment of the motor and pump shafts was performed. The graph at the right shows the before and after alignment condition.

The vibration trend of the alignment parameter band decreased back to normal levels after the shaft alignment job.

Integrated report showing the Vibration and Infrared Data and an Explanation and Urgency of the problem.

Explanation

Vibration Trend

Urgency

IR Thermogram

Analisis Multi-Teknologi

– Vibration• FFT, waveform, & phase analysis• Automated diagnostics

WAVEFORM DISPLAY

18-OCT-94 08:37:00

RMS = 4.38

PK(+) = 14.53

PK(-) = 11.78

CRESTF= 3.32

0 50 100 150 200 250 300 350

-15

-12

-9

-6

-3

0

3

6

9

12

15

Time in mSecs

Acc

eler

atio

n in

G-s

CF ALARM

CF ALARM

PK ALARM

PK ALARM

MA#7 - GEARBOX DRIVE-SUCTION ROLL

GBX-DSROLL-G3R G-BOX OUTPUT SHAFT - RADIAL

Label: Severe BPFO defect - need action

Priority: 4

ROUTE SPECTRUM

18-OCT-94 08:37:00

OVRALL= .6516 V-DG

PK = .6892

LOAD = 100.0

FPM = 3518.

RPM = 381.

0 400 800 1200 1600

0

0.1

0.2

0.3

0.4

0.5

0.6

Frequency in Hz

PK

Vel

oci

ty in

In/S

ec

Freq:

Ordr:

Spec:

79.29

12.50

.04412

>FAG 61896

G=BPFO

G G G G G G G G G G

BPFO harmonics show severe race defect

– Tribology• Trivector wear, chemistry, &

contamination analysis

– Alignment & Balancing• Tolerance plots by the job

– Motor Monitoring• Automated rotor & stator

diagnostics with current & flux

– Thermography• Palette & plot annotation tools• Temp profile & histogram analysis

MTR - Forced Draft w/ Broken Bars

450 HP MTR-RB1 Current Rotor Bar Analysis Ph=1

Label: MOTOR WITH 4 BROKEN ROTOR BARS

Spectrum Display

07-DEC-90 09:25

AMPS = 43.32

LOAD = 65%

RPM = 711.

RPS = 11.85

50 52 54 56 58 60 62 64 66 68 70

0

10

20

30

40

50

60

70

Frequency in Hz

dB

AM

PS

CASE HISTORIES

! BEARING DEFECT ON NASH VACUUM PUMP

! FIELD BALANCING

! HIGH VIBRATION ON VERTICAL PUMP

Kerusakan Bearing Pompa

MIVMIHMIA

PIVPIHPIA

POVPOHPOA

MOVMOH

#1 #3#2 #4

•Pompa vacuum di PTA Plant•Critical Equipment•Vibrasi tinggi

Kerusakan Bearing Pompa

PK

Vel

oci

ty in

mm

/Sec

Frequency in Hz

PT4 - NASH Vacuum Pump FJ-10NVP - PTS=POV POH POA (26-APR-00)

0 200 400 600 800 1000

Max Amp 5.30

Plot Scale

0

3

NVP -POV

NVP -POH

NVP -POA

Spektrum pada Pump Outboard Bearing, frekuensi bearing muncul

Kerusakan Bearing PompaPT4 - NASH Vacuum Pump FJ-10

NVP -POV Pump Outboard Vertical

Route Spectrum 26-APR-00 16:14:04

OVRALL= 12.94 V-DG PK = 12.96 LOAD = 100.0 RPM = 742. RPS = 12.36

0 20 40 60 80 100

0

1

2

3

4

5

6

7

Frequency in Order

PK

Vel

oci

ty in

mm

/Sec

>TMK 71450 CONE C=BPFO

C C C C C C C

ANALYZE WAVEFORM 26-APR-00 16:09:13 (PkVue-HP 1000 Hz) RMS = 11.73 PK(+) = 102.51 PK(-) = 13.21 CRESTF= 8.74

0 50 100 150 200 250 300 350 400

-20

0

20

40

60

80

100

120

Time in mSecs

Acc

eler

atio

n in

G-s

PT4 - NASH Vacuum Pump FJ-10NVP -POH Pump Outboard Horizontal

ANALYZE SPECTRUM 26-APR-00 16:09:13 (PkVue-HP 1000 Hz) RMS = 11.91 LOAD = 100.0 RPM = 740. RPS = 12.33

0 20 40 60 80 100

0

1

2

3

4

5

6

7

Frequency in Order

RM

S A

ccel

erat

ion

in G

-s

>TMK 71450 CONE D=BPFI

D D D D D D

Inner race defect !!

Outer race defect !!

Field Balancing

GENERATOR

GOVGOHGOA

R4VR4HR4A

R3VR3HR3A

TOVTOHTOA

R1VR1HR1A

R2VR2HR2A

TURBINEGEARBOX

Gearbox outboard

Gearbox inboard

Generatoroutboard

Turbineinboard

Figure.1 Machine diagram of DGT-7

Equipment Description

! GE Gas turbine coupled with generator ! Capacity 25 MW! Turbine speed = 5100 RPM! Generator speed = 3600 RPM! Configuration : Turbine – Gearbox – Generator! Bearing type : journal bearing

Before & After Balancing

PK

Vel

oci

ty in

In/S

ec

Frequency in kCPM

PGTD - Duri Gas Turbine 7DGT-7 - PTS=GOV GOH

0 20 40 60 80 100 120

Max Amp .53

Plot Scale

0

1.2

16-DEC-99 09:18DGT-7 -GOV

21-DEC-99 15:01DGT-7 -GOV

16-DEC-99 09:20DGT-7 -GOH

21-DEC-99 14:58DGT-7 -GOH

before balancing

after balancing

before balancing

after balancing

Keuntungan PdM

! Menghindari unschedule breakdown

! Menjamin Reliability & Availability

! Inventory control

! Menjaga kelangsungan proses produksi

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