bab i. pendahuluan - laskar teknik · pdf file• start up cycle: kerusakan terjadi karena...

PERAWATAN MESIN MS-4102(MAINTENANCE)

BAB I. PENDAHULUAN

PRODUCT LIFE CYCLE• Feasibility Study: apakah suatu mesin/pabrik layak

dibuat ditinjau dari segi ekonomi, lingkungan, teknologi.• Design: gambar desain dan spesifikasi teknik.• Build: tender, gambar konstruksi, konstruksi, as built

drawing • Commissioning: pengujian terhadap performance yang

dijanjikan, base line data.• Operation (untuk menghasilkan produk) & Maintenance

(supaya mesin tetap dapat dioperasikan dengan baik). • Decommissioning: untuk menentukan apakah mesin

sudah mencapai akhir umurnya.• Discard: mesin dibuang dan materialnya didaur ulang.

WHAT IS MAINTENANCE?Contoh:

Kita punya sebuah motor.

Apa yang kita lakukansupaya motor tetap dapatberfungsi dengan baik?

Apa tujuan kita memilikisepeda motor? Umumnyatujuan non komersial. Untung rugi bukanpertimbangan.

WHAT IS MAINTENANCE?• Yang kita lakukan (elemen aktifitas perawatan)

– Membersihkan (lap, cuci)– Memeriksa (dapat dilakukan sambil membersihkan)– Mengencangkan (mur/baut, jari2 yang kendor, rantai, memompa

ban, menyetel arah kaca spion, menyetel rem)– Melumasi (rantai, kabel rem, pedal rem)– Menyediakan suku cadang (bohlam, busi)– Perbaikan ringan (dilakukan sendiri)– Perbaikan berat (dilakukan oleh bengkel)

• Tujuan– Supaya performancenya tetap baik (performance mesin,

tampilan)– Aman dikendarai– Tidak mencemari lingkungan

WHAT IS MAINTENANCE?Kita punya armada motor (untukojek).

Tujuan komersial: untung rugimerupakan pertimbangan penting.

Motor harus dijaga supaya tetapproduktif dan tidak rewel.

Melibatkan banyak orang: perludigaji, perlu koordinasi.

Inventarisasi: merek motor, tahunpembuatan, jadwalpengoperasian, jadwal perawatan.

WHAT IS MAINTENANCE?

WHAT IS MAINTENANCE?• Untuk suatu pabrik apa yang dilakukan dan tujuannya

serupa dgn untuk motor.• Jumlah orang yang terlibat lebih banyak• Jumlah dana lebih banyak• Aspek komersial memerlukan pengorganisasian semua

kegiatan:– Strategi perawatan– Penugasan & koordinasi– Inventarisasi aset dan SDM– Penyediaan suku cadang– Pembelian barang dan jasa– Sistem informasi– Perencanaan perawatan/perbaikan– Penjadwalan perawatan/perbaikan


Pabrik dengan jumlah peralatan dan jenis sangat banyak.• Peralatan putar (rotating equipments)

– Pompa, kompresor, turbin, diesel• Peralatan statik (tidak berputar)

– Pressure vessels, reaction column, knocking drum, heat exchanger, tangki, piping

• Elektrik– Motor listrik, generator, transformer, distribution panels

• Instrumen dan sistem kendali– Pressure gauge, termometer, level meter, flow meter– PLC, DCS– Hidrolik, pneumatik

• Bangunan, prasarana (jalan, gedung, platform, air, bengkel, dlsb)

WHAT IS MAINTENANCE?• Asal kata : to maintain• Arti: (1) memelihara• Arti: (2) merawat• Arti: (3) menjaga• Apa yang di maintain?

– mesin/peralatan: supaya tidak rusak– performance (kualitas, kuantitas, efisiensi): supaya

memenuhi kriteria– aspek keselamatan: supaya tidak membahayakan

personil– aspek lingkungan: supaya tidak mencemari

lingkungan


Per

form

ance

Waktu

DenganPM

Performance Min

TanpaPM

WHAT IS MAINTENANCE?P

erfo

rman

ce

Waktu

CM CM

PM

Maintenance record

Performance min

WHAT IS MAINTENANCE?• Teknik (bayangkan anda hanya menghadapi 1 motor)

– Bagaimana melumasi– Bagaimana cara menyetel– Bagaimana cara membongkar & memasang– Bagaimana cara mendeteksi kerusakan

• Manajemen (bayangkan anda mempunyai 100 motor)– Bagaimana menyediakan “personil”, menentukan tugas dan

wewenangnya– Mendidik, melatih dan menyemangati personil– Merekam data dan informasi– Bagaimana menyediakan dan membeli suku cadang– Bagaimana membuat planning– Bagaimana menjadwal– Bagaimana menyediakan dana– Bagaimana mengorganisasikan (visi, misi)

WHAT IS MAINTENANCE?• Teknik

– Fokus ke mesin, lebih jelas (bukan berarti mudah)– Ada manual teknik dari pembuat mesin– Ada catatan sejarah perawatan mesin– Ada code dan standard (SNI, API, ASME, JIS, DIN dlsb)– Ada peraturan keselamatan kerja, peraturan lingkungan hidup,

OSHA (Occupational Safety and Hazard Association)• Manajemen

– Fokus ke manusia– Ada ilmunya tapi tidak “exact” seperti yang teknik– Melibatkan unsur “seni”– Dipengaruhi budaya setempat (etos kerja, disiplin, rasa memiliki)– Tergantung xxxx

WHAT IS MAINTENANCE?• Unplanned maintenance: kegiatan perawatan tidak terjadwal

karena keadaan darurat.• Planned maintenance: kegiatan perawatan terjadwal (biasanya

jangka panjang/tahunan). Seringkali mesin produksi tidak dapatdihentikan begitu saja untuk maintenance.

• Breakdown maintenance (RTF = Run To Failure): strategiperawatan dimana mesin dibiarkan saja beroperasi sampaikerusakan terjadi.

• Preventive maintenance: strategi perawatan (cleaning, inspection, small repair, lubrication) untuk mencegah konsekuensi kegagalanpada tingkat komponen maupun tingkat pabrik.

• Corrective maintenance: adalah strategi untuk memperbaikikomponen yang mengalami kegagalan.

• Running maintenance: kegiatan maintenance yang dapatdikerjakan ketika mesin sedang beroperasi

• Shutdown maintenance: kegiatan maintenance yang hanya dapatdikerjakan ketika mesin sedang tidak beroperasi

WHAT IS MAINTENANCE?• Emergency maintenance: kegiatan perawatan/

perbaikan untuk mengatasi kerusakan yang tidakterduga.

• Availability: ketersediaan/kesiapan mesin utkdioperasikan

• MTBF (mean time between failure): jangka waktuantara dua kerusakan berturut-turut.

• MTTR (mean time to repair): jangka waktu untukmenyelesaikan perbaikan.

• Down time: periode waktu dimana mesin tidak dapatdioperasikan

• Facility register (master equipment list): basis data peralatan, termasuk komponen dan perlengkapannya.

WHAT IS MAINTENANCE?• Maintenance management: pengelolaan kegiatan perawatan• Maintenance planning: perencanaan kegiatan perawatan selama 1

tahun.• Maintenance scheduling: penjadwalan kegiatan perawatan

selama 1 tahun.• Overhaul: membongkar mesin sebagian atau keseluruhan dan

memperbaikinya supaya diperoleh kondisi sesuai standar.• User: pengguna• Owner: pemilik• Vendor: penyedia alat/mesin• Efficiency: running hours / (running hours + down time)• Trip: mesin mati secara otomatis karena ada parameter operasi

(suhu, getaran dll) yang melebihi batas aman.• Shut in: mesin dimatikan secara sengaja.• Shut down: mesin mati dengan sendiri.


Maintenance

Planned maintenance Unplanned maintenance

Preventive maintenance

Corrective maintenance Emergency

maintenance

Overhaul

Minor Major

Shutdown maintenance

•Cleaning

•Inspection

•Small repair

Running maintenance

WHY DO MACHINES FAIL?• Wajar

– Aus (wear): scuffing, galling, fretting, abrasion – Lelah (fatigue)– Karat (corrosion)– Erosi (erosion)– Penuaan (aging)

• Prematur– Pelumasan tidak bagus (kualitas, kuantitas pelumas,

periode penggantian pelumas tidak benar)– Kotor/kontaminasi– Overheated– Misalignment (pada kopling, bearing, belt, rantai)

WHY DO MACHINES FAIL?OverheatedBrinelling karena overloaded

WHY DO MACHINES FAIL?

Fatigue damage

FAILURE PATTERN• Dahulu orang percaya bahwa semua kegagalan

komponen mengikuti “bathtub curve”• Ternyata bathtub curve tsb hanya mencakup 4% dari

populasi komponen (mis: bearings, connector, switches, IC, PCB, etc)

• Age related failure hanya 11%

Failu

re R

ate

Time

Useful life period

(wealth cycle)

Start up cycle

Break down cycle

Critical wear point

FAILURE PATTERNArti dari bathtub curve• Start up cycle: kerusakan terjadi karena ketidak

sempurnaan material, pengerjaan, pemasangan, pelatihan operator. Pada saat awal komponen mesinakan saling menyesuaikan karena berbagai ketidaksempurnaan pembuatan (permukaan masih kasar yang saling menghaluskan)

• Useful life: mesin berproduksi dengan baik karenakomponen2nya sudah saling menyesuaikan

• Break down cycle: komponen mengalami fatigue, keausan berlebih, erosi, abrasi dlsb.

Bath tube curve cocok untuk komponen mekanik.

FAILURE PATTERN

7%

14%

68%

2%

5%

4%

Age related failure (1, 2, 3)

Artinya: komponen akanrusak ketika sudah tua

Age unrelated failure (4, 5, 6)

Artinya: komponen bisagagal secara random, padasaat masih muda maupunsesudah tua

FAILURE PATTERN POPULATION PERCENTAGE

1

2

3

4

5

6

FAILURE PATTERN

1940 1950 1960 1970 1980 1990 2000

Kategori Mesin/Peralatan Produksi

• Ditinjau dari tingkat kerumitan, harga, peranan dan resiko dalam suatu matarantai produksi, mesin digolongkan atas. – Critical– Essential (Potentially critical)– General Purpose (Non critical)

• Kategori ini untuk menentukan strategiperawatan yang cocok.

Mesin “Critical”

• Kalau rusak dapat membahayakan• Kalau rusak proses produksi terganggu• Investasi mahal• Biaya perbaikannya mahal (misal: high

speed turbine)• Waktu untuk perbaikan lama

Mesin “General Purpose”

• Kalau rusak tidak membahayakan• Kalau rusak tidak mengganggu proses

produksi• Investasi tidak mahal• Biaya perbaikan tidak mahal• Mempunyai unit cadangan• Tidak mengakibatkan kerusakan sekunder

Mesin Essential (Potentially Critical)

• Di antara mesin critical dan general purpose.

BAB II PERKEMBANGAN

STRATEGI PERAWATAN

PERKEMBANGAN STRATEGI PERAWATAN

• Sebelum PD II rancangan mesin sederhana, kokoh, berat, “robust”

• Perawatan sederhana• Munculnya sistem produksi massal berarti

kerusakan mesin produksi dapat menimbulkankerugian besar

• Bersamaan dgn itu, rancangan mesinbertambah rumit, ringan, ramping

• Perlu strategi baru dalam perawatan


Generasi ketiga-Availability dan reliability lebih

baik-Keselamatan lebih baik-Kualitas produk lebih baik-Tidak mencemari lingkungan-Umur peralatan lebih panjang-Efektifitas biaya lebih baik

Generasi kedua-Availability lebih baik-Umur peralatan lebih

panjang-Efektifitas biaya lebih baik

Generasi pertama-Perbaiki kalau rusak

Tuntutan yang semakin meningkat thd maintenance

1940 1950 1960 1970 1980 1990 2000


Generasi ketiga-Pemantauan kondisi mesin-Design for reliability and

maintainability-Hazard studies-Komputer kecil, cepat-FMEA-Expert systems-Multi tasking and teamworks

Generasi kedua-Overhaul terjadwal-Sistem utk perencanaan dan

pengendalian kerja-Komputer besar dan lambat

Generasi pertama-Perbaiki kalau rusak

1940 1950 1960 1970 1980 1990 2000

PERKEMBANGAN FILOSOFI PERAWATAN

• Break down (run to failure) maintenance : mesindioperasikan tanpa perawatan sampai kerusakan terjadi. Kerusakan primer hampir selalu menimbulkan kerusakansekunder.

• Preventive maintenance (PM) atau time base maintenance: mesin di”maintain” secara terjadwalsetelah beroperasi dalam jangka waktu tertentu.

• Predictive (on condition based) maintenance (PdM): kondisi mesin dipantau secara menerus. Bila terdeteksiadanya ketidak normalan baru diambil tindakan.

• Proactive (prevention) maintenance: kerusakan yang terjadi dicari penyebabnya untuk mencegah kerusakanyang sama berulang.

PERKEMBANGAN FILOSOFI PERAWATAN

2 year leaseAutomobile tiresOil changeHead lightComponent you would maintain

Could be expensive

Costly if implemented incorrectly

Unnecessary replacement of parts. Poor utilization of labor.

High spare stock level.Emergency outages

Disadvantages (when implemented correctly)

Less maintenance required

Can spot potential failure

Can be planned for or scheduled

CheapAdvantages (when implemented correctly)

Redesign to eliminate root cause of failure

Maintain based upon known condition/standard

Conduct maintenance at regular intervals

Fix it when it breaks, Run to Failure

Definition

Proactive Maintenance

Predictive Maintenance

Preventive Maintenance

Reactive,Run To Failure

Strategy

RunRun--toto--Failure MaintenanceFailure Maintenance

•• RunRun--toto--failure maintenance is sometimes failure maintenance is sometimes called "crisis maintenance" for good called "crisis maintenance" for good reason. This has been the dominant form reason. This has been the dominant form of maintenance for a long time, and its of maintenance for a long time, and its costs are relatively high because of costs are relatively high because of unplanned downtime, damaged unplanned downtime, damaged machinery, and overtime expenditure. machinery, and overtime expenditure.

•• REACTIVEREACTIVE::–– Trouble / Breakdown / RTF / M&RTrouble / Breakdown / RTF / M&R

•• ““Fix it when it breaksFix it when it breaks”” –– ““Run to failureRun to failure””

•• PREVENTIVEPREVENTIVE (PM): (PM): Functional Checks of EquipmentFunctional Checks of Equipment–– For Rotating Equipment:For Rotating Equipment:

•• LubricationLubrication•• BeltsBelts•• FiltersFilters•• HousekeepingHousekeeping•• Visual ObservationsVisual Observations

–– Work Orders generated Facility Asset Management Work Orders generated Facility Asset Management Information SystemInformation System

Periodic Preventive MaintenancePeriodic Preventive Maintenance•• Periodic preventive maintenance, which is sometimes called Periodic preventive maintenance, which is sometimes called

"historical" maintenance. This is where the histories of each "historical" maintenance. This is where the histories of each machine type are analyzed and periodic overhauls are scheduled tmachine type are analyzed and periodic overhauls are scheduled to o occur before the statistically expected problems occur. It has loccur before the statistically expected problems occur. It has long ong been known that most groups of similar machines will exhibit faibeen known that most groups of similar machines will exhibit failure lure rates that are somewhat predictable if averaged over a long timerates that are somewhat predictable if averaged over a long time. . This gives rise to the soThis gives rise to the so--called "Bathtub Curve" which relates failure called "Bathtub Curve" which relates failure rate to operating time, as follows:rate to operating time, as follows:

PREVENTIVE MAINTENANCE (TIME BASED)

• Preventive maintenance adalah suatu tindakan untukmenjaga agar peralatan tetap dapat beroperasi dengancara inspeksi, deteksi dan pencegahan kerusakan.

• Semua kegiatan perawatan dijadwal berdasar waktu(mingguan, bulanan, triwulanan, 1000 jam, 3000 jam dlsb)

• Pelaksanaan mudah, tinggal mengikuti jadwal: pembersihan, pengecatan, pelumasan, pemeriksaan, perbaikan.(Rencana dan jadwal tahunan harusdisiapkan).

• Penganggaran mudah: anggaran umumnya dibuattahunan.


• Murphy Law: Kerusakan biasanya terjadi pada waktuperalatan sangat dibutuhkan.

• Contoh: Pada saat banyak order, peralatan produksirusak. Perbaikan dapat memakan waktu beberapa jam atau beberapa hari.

• Hal yang tidak menguntungkan ini dapat dicegah denganPM.

• Alasan lain: keselamatan, penghematan biaya perbaikankarena kerusakan sekunder.


Peralatan apa yang cocok untuk di PM?• Peralatan yang menyebabkan :

– “major shut down”, – penurunan kualitas produk, – kerusakan terhadap komponen terkait, – bahaya kepada karyawan

• Penerangan, lantai, plafon yang dapat mengganggukualitas produksi atau menimbulkan kondisi kerja yang buruk.


Peralatan apa yang tidak perlu di PM? (cukup dg RTF)• Peralatan yang mempunyai cadangan• Peralatan yang harganya lebih rendah dari biaya PM• Peralatan yang umur harapannya cukup panjang tanpa

PM

Example• 3 pumps of exactly the same type and manufacturer, however, each

requires different maintenance strategy.– Pump A: Preventive maintenance (PM)– Pump B: Break down maintenance (RTF)– Pump C: Periodic test to eliminate hidden failure or PM

Pump A (continuous running)

Pump B (continuous running)

Pump C (standby, hidden failure)

100 l/min cooling water

100 l/min cooling water

Production Train 1

Loss USD 200,000./day when stop

Production Train 1Loss USD 200,000./day when stop

Example• 3 pumps of exactly the same type and manufacturer• Pump A: Predictive maintenance ???• Pump B: Break down maintenance???• Pump C: Periodic test???

Pump A (continuous running)

Pump B (continuous running)

Pump C (standby, hidden failure)

100 l/min nitric acid

100 l/min nitric acid

Production Train 1

Loss USD 200,000./day when stop

Production Train 1Loss USD 200,000./day when stop


PM

cos

t

% maintenance delay

Lebih banyak uang untuk PM, terjadisedikit keterlambatan

Lebih sedikit uang untuk PM, terjadi banyak keterlambatan


Cos

t

% maintenance delay

Production cost due to delay

Production cost as affected by maintenance cost

PM cost#1

#3

#2


• #1: terlalu banyak PM, menghamburkan tenaga, sukucadang dan uang.

• #2: sangat kurang, akan terjadi banyak kerusakan• #3: sangat optimum, tapi jarang tercapai. Indikasinya

20% peralatan mengalami kerusakan sebelumdiperbaiki.

• Bila tidak terjadi kerusakan sebelum diperbaiki berartiPM terlalu banyak.


• Rumus empirik untuk menentukan faktor PM (makintinggi nilainya PM makin perlu)

PM = D(A+B+C)/(EF)PM = inspection factorD = number of break down/yearA = cost of break down repairsB = cost of lost productionC = cost of repairing other equipment involved in the

breakdownE = cost of PM activity (average)F = number of PM cycle per year


Do PM (Preventive Maintenance) if number of break down x Average cost per break down x 70% > cost of PM system


Optimum Frequency/Interval for PM ditentukan berdasar:• Failure history• CM history• Manufacturer recommendations• Industry history• Regulatory requirements• Design and operation considerations• Other tasks scheduled on the same component• Planned outages• Ability to gain access to the component• Operator capability• PdM monitoring activity• Environment

PM Tasks

Ask operator how machine is operatingInterview operatorHistory analysis of a type of machineAnalysisRemove and replace pumpScheduled replacementAdd oilLubricateRead temperature, pressure, vibrationTake readingAdjust tightening boltAdjustingWarming up machine/prepare for operationOperatingTighten anchor boltsTighteningRemove debris from machinesCleaningLook for leak in hydraulic systemInspectionExampleType of Task


Inspection• Memastikan performansi peralatan sesuai perancangan• Mengevaluasi semua komponen terhadap masalah yang

potensial menimbulkan kerusakan• Mengidentifikasi komponen yang dapat menyebabkan

kerusakan dan mengestimasi waktu sampai kerusakanterjadi. Contoh: dinding pressure vessel mengalamipenipisan selama dioperasikan.


Inspeksi dilakukan• Karena tuntutan peraturan: Pressure vessel harus

diinspeksi secara berkala sesuai dengan peraturanpemerintah tentang keselamatan kerja.

• Karena mesin tidak dilengkapi dengan cadangan danberesiko terhadap keberlangsungan proses produksi.

• Pada peralatan yang sedang rusak

CORRECTIVE MAINTENANCE (PERBAIKAN) SEBAGAI RESPONS TERHADAP INSPEKSI DALAM PM

Biaya perbaikan

Equ

ipm

ent a

vaila

bilit

y

PREDICTIVE MAINTENANCE (PdM)

Preventive Maintenance

Time Based Maintenance

Predictive Maintenance,

Condition Based Maintenance

Predictive MaintenancePredictive Maintenance•• Predictive maintenance allows management to control Predictive maintenance allows management to control

the machinery and maintenance programs rather than the machinery and maintenance programs rather than vice versa. In a plant using predictive maintenance, the vice versa. In a plant using predictive maintenance, the overall machinery condition at any time is known, and overall machinery condition at any time is known, and much more accurate planning is possible.much more accurate planning is possible.

•• Benefits of Predictive MaintenanceBenefits of Predictive Maintenance–– The major benefit of predictive maintenance of The major benefit of predictive maintenance of

mechanical equipment is increased readiness due to mechanical equipment is increased readiness due to greater reliability of the equipment. The trending over greater reliability of the equipment. The trending over time of developing faults in machines can be carefully time of developing faults in machines can be carefully done so as to plan maintenance operations to done so as to plan maintenance operations to coincide with scheduled shutdownscoincide with scheduled shutdowns..

SAAT PERAWATAN YANG TEPAT

Predictive Maintenance (PdM). Perbaikan tepat pada waktunya

Time based preventive maintenance (PM)

Mesin terlambatdiperbaiki

Perbaikan dilakukanterlalu awal

Predictive Maintenance TechnologiesPredictive Maintenance Technologies

•• Infrared Infrared ThermographyThermography•• Lubrication analysisLubrication analysis•• Vibration AnalysisVibration Analysis

Energy and Power ConsiderationsEnergy and Power Considerations

•• Energy is required to produce vibration and in the case Energy is required to produce vibration and in the case of machine vibration, this energy comes from the source of machine vibration, this energy comes from the source of power to the machine. This energy source can be the of power to the machine. This energy source can be the AC power line, an internal combustion engine, or steam AC power line, an internal combustion engine, or steam driving a turbine, etc. Energy is defined as force driving a turbine, etc. Energy is defined as force multiplied by the distance over which the force acts, and multiplied by the distance over which the force acts, and the SI unit of energy is the Joule. One Joule of energy is the SI unit of energy is the Joule. One Joule of energy is equivalent to a force of one Newton acting over a equivalent to a force of one Newton acting over a distance of one meter. The physical concept of work is distance of one meter. The physical concept of work is similar to that of energy, and the units used to measure similar to that of energy, and the units used to measure work are the same as those for measuring energy.work are the same as those for measuring energy.

Energy and Power ConsiderationsEnergy and Power Considerations•• The actual amount of energy present in the machine vibration itsThe actual amount of energy present in the machine vibration itself elf

is usually not very great compared to the energy required to opeis usually not very great compared to the energy required to operate rate the machine for its intended task.the machine for its intended task.

•• Power is defined as the rate of doing work, or the rate of energPower is defined as the rate of doing work, or the rate of energy y transfer, and according to the SI, it is measured in Joules per transfer, and according to the SI, it is measured in Joules per second, or Watts. One horsepower is equivalent to 746 watts. Powsecond, or Watts. One horsepower is equivalent to 746 watts. Power er is proportional to the square of the vibration amplitude, just ais proportional to the square of the vibration amplitude, just as s electrical power is proportional to the voltage squared or the celectrical power is proportional to the voltage squared or the current urrent squared.squared.

•• According to the law of conservation of energy, energy cannot beAccording to the law of conservation of energy, energy cannot becreated or destroyed, but it can be transformed into different fcreated or destroyed, but it can be transformed into different forms. orms. The vibratory energy in a mechanical system is ultimately dissipThe vibratory energy in a mechanical system is ultimately dissipated ated in the form of heat.in the form of heat.

PROACTIVE MAINTENANCE (PREVENTION MAINTENANCE)

• Kerusakan premature (belum saatnya) dapatterjadi atas peralatan

• Mencegah perbaikan berulang atas kerusakanpremature

• Kerusakan jenis tersebut harus dicaripenyebabnya dengan Root Cause Failure Analysis (RCFA)

• Improvement/redesign komponen dilakukanberdasar hasil RCFA

Proactive Maintenance Proactive Maintenance TechnologiesTechnologies

•• Dynamic BalancingDynamic Balancing•• Precision Shaft AlignmentPrecision Shaft Alignment•• Ultrasonic Testing / Air & SteamUltrasonic Testing / Air & Steam•• Belt / Pulley AlignmentBelt / Pulley Alignment•• Acceptance TestingAcceptance Testing•• Water / Air Flow balancing & MeasuringWater / Air Flow balancing & Measuring•• MeteringMetering

ProPro--active Maintenanceactive Maintenance

•• ProPro--active maintenance, which uses a variety of active maintenance, which uses a variety of technologies to extend the operating lives of technologies to extend the operating lives of machines and to virtually eliminate reactive machines and to virtually eliminate reactive maintenance. The major part of a promaintenance. The major part of a pro--active active program is root cause failure analysis (RCA), program is root cause failure analysis (RCA), which is the determination of the mechanisms which is the determination of the mechanisms and causes of machine faults. The fundamental and causes of machine faults. The fundamental causes of machine failures can thus be causes of machine failures can thus be corrected, and the failure mechanisms can be corrected, and the failure mechanisms can be gradually engineered out of each machinery gradually engineered out of each machinery installation.installation.

Maintenance Strategy Comparation

Heart attack or strokeLarge maintenance budget

Break down, Run To Failure, Reactive

By-pass or transplant surgery

Periodic components replacement

Preventive

Detection of heart disease by ECG or ultrasonic

Monitoring of vibration, temperature, alignment, pressure, wear debris

Predictive

Cholesterol and blood pressure monitoring, followed by diet control

Monitoring and correction of “failing root causes”

Proactive

Human Health ParallelTechnique NeededMaintenance Strategy

RCM (Reliability Centered Maintenance)


Reactive, RTF

PM, Time Based

PdM, Condition Based, Predictive

Proactive

•Small items

•Non critical

•Inconsequential

•Unlikely to fail

•Redundant

•Subject to wear out

•Consumable replacement

•Failure pattern known

•Random failure patterns

•Not subject to wear

•PM Induced failures

•Age exploration

•RCFA

•FMEA

•Acceptance testing

RCFA = Root Cause Failure Analysis

FMEA = Failure Mode and Effect Analysis

RULES FOR BREAKDOWN MAINTENANCE

• If equipment is redundant• Low cost spares available• Interruptible process, stock pile• Safe failure modes• Long MTTF/MTBF• Low cost secondary damage• Quick repair/replacement (low cost of interuption

of production)

RULES FOR PREVENTIVE MAINTENANCE

• Statistical failure rate available• Narrow failure distribution (predictable MTBF)• Maintenance restore full integrity• Single failure mode (known)• Low cost of regular overhaul/replacement• Unexpected interruption to production is

expensive (scheduled interruption is not so bad)• Low cost spares available• Reduced number of breakdown is required• Costly secondary damage

RULES FOR PREDICTIVE MAINTENANCE

• Expensive/critical machinery• Long lead time for replacement (no spares)• Uninterruptible process (both regular and unexpected)-

costly• Large/complex machinery• Overhaul expensive (need highly trained people)• Reduced number of highly skilled maintenance people• Cost of monitoring program is acceptable• Safety is priority (failure dangerous)• Remote/mobile equipment• Failure is not indicated by operation degeneration• Costly secondary damage

ALIRAN INFORMASI

Dari mana pekerjaan perawatan bermula?• Internal (dari dalam department of

maintenance): tugas preventive maintenance dan corrective maintenance

• Eksternal (dari luar departemen): permintaan dari manajer produksi, rehabilitasi

Komponen Penting dalamPerawatan

Gunung Es Perawatan

Organisasi Perawatan

bab i. pendahuluan - laskar teknik · pdf file• start up cycle: kerusakan terjadi karena...

Documents