Boost Compressor
Transcript of Boost Compressor
SOLAR GAS BOOST SOLAR GAS BOOST COMPRESSOR OUTLINECOMPRESSOR OUTLINEPengenalan Centrifugal Gas CompressorPengenalan Centrifugal Gas CompressorPrinsip Kerja Gas CompressorPrinsip Kerja Gas CompressorCompressor Component dan FungsinyaCompressor Component dan FungsinyaStaging SelectionStaging SelectionPerformance EvaluationPerformance EvaluationCompressor Cleaning / StripdownCompressor Cleaning / StripdownRestageRestage
Pengenalan Centrifugal Gas Pengenalan Centrifugal Gas CompressorCompressor
Centrifugal Gas Compressor adalah salah satu Centrifugal Gas Compressor adalah salah satu Compressor yang termudah yang ada untuk Compressor yang termudah yang ada untuk menaikan tekanan dari gas dengan aliran menaikan tekanan dari gas dengan aliran kontinyu. kontinyu. Solar Compressor FamilySolar Compressor Family
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Prinsip Kerja Gas Boost Prinsip Kerja Gas Boost CompressorCompressor
Prinsip Kerja Centrifugal Gas Prinsip Kerja Centrifugal Gas Compressor adalah mengubah Compressor adalah mengubah energy kecepatan dari gas menjadi energy kecepatan dari gas menjadi energy tekanan dan Fungsinya untuk energy tekanan dan Fungsinya untuk menaikan tekanan dari gas untuk menaikan tekanan dari gas untuk keperluan tertentu. keperluan tertentu.
Gas Flow Through Impeller
Compressor Stage Component
Compressor ComponentCompressor Componentdan Fungsinyadan Fungsinya
Casing & End Cap.Casing & End Cap.RotorRotorStatorStatorBearingBearingSealSeal
Housing & End CapHousing & End CapSebagai manifold / penampungan Sebagai manifold / penampungan
gas inlet (suction cavity) dan gas gas inlet (suction cavity) dan gas outlet (discharge cavity) yang outlet (discharge cavity) yang designnya pressurenya designnya pressurenya disesuaikan dengan Kondisi disesuaikan dengan Kondisi operasinya / operating point.operasinya / operating point.
Housing & End CapHousing & End CapGas Compressor C-304
StatorStatorMerupakan bagian yang diam / stationary yang Merupakan bagian yang diam / stationary yang
terdiri dari :terdiri dari :-- Guide Vane Guide Vane -- Diffuser.Diffuser.
Guide Vane berfungsi sebagai pengarah dari aliran Guide Vane berfungsi sebagai pengarah dari aliran untuk menuju ke impeller.untuk menuju ke impeller.
Diffuser berfungsi untuk mengubah energy Diffuser berfungsi untuk mengubah energy mekanik / gerak dalam hal ini kinetik energy mekanik / gerak dalam hal ini kinetik energy menjadi energy tekanan / pressure.menjadi energy tekanan / pressure.
RotorRotorMerupakan susunan dari beberapa Merupakan susunan dari beberapa buah impeller yang stagingnya telah dibuah impeller yang stagingnya telah disesuaikan dengan kebutuhansesuaikan dengan kebutuhanoperasinya dan berfungsi untukoperasinya dan berfungsi untukmempercepat aliran gas sebelummempercepat aliran gas sebelummemasuki diffuser daipada statormemasuki diffuser daipada stator
RotorRotor
Center StudPin
BearingBearingBerfungsi untuk meredam getaran yang ditimbulkan Berfungsi untuk meredam getaran yang ditimbulkan oleh compressor dan type yang digunakanoleh compressor dan type yang digunakankebanyakan adalah Hydrodynamic journal bearingkebanyakan adalah Hydrodynamic journal bearingyang lazim kita sebut sebagai tilt pad bearingyang lazim kita sebut sebagai tilt pad bearing
Alasan kenapa memilih Tilt pad bearing Alasan kenapa memilih Tilt pad bearing -- Effekivitas untuk meredam getaran sangat tinggiEffekivitas untuk meredam getaran sangat tinggi-- Meniadakan oil whirl / oil whipMeniadakan oil whirl / oil whip-- Life timenya relative lama Life timenya relative lama
Tilting Pad BearingTilting Pad Bearing
Thrust Bearing• Berfungsi untuk menahan gaya axial
• Ada dua macam type– Tilt pad thrust bearing– Non Tilt pad thrust bearing
• Ada yang dilengkapi dengan sensor, untuk memonitor thrust bearing temperature
Tilt Pad Thrust Bearing
Pad
Temperature sensor
SealsSealsSeal System terdiri :Seal System terdiri :-- Labyrinth : Labyrinth : Bentuknya sekatBentuknya sekat--sekat yang tiap ujungnya berbertuksekat yang tiap ujungnya berbertukruncing / tajam dan berada dikedua sisi impeller atau stubruncing / tajam dan berada dikedua sisi impeller atau stubshaft dan berfungsi untuk meminimize / mengurangishaft dan berfungsi untuk meminimize / mengurangikebocoran gas diantara tiapkebocoran gas diantara tiap--tiap stage didalamtiap stage didalamcompressor .compressor .
-- Buffer Gas / Seal GasBuffer Gas / Seal GasBerfungsi untuk menjaga agar seal oil / lubrikasi tidakBerfungsi untuk menjaga agar seal oil / lubrikasi tidakmasuk kedalam compressor / processmasuk kedalam compressor / process
-- Seal Oil Seal Oil Berfungsi untuk menjaga agar process gas tidak masukBerfungsi untuk menjaga agar process gas tidak masukkedalam system pelumasan / lubrikasi. kedalam system pelumasan / lubrikasi.
Labyrinth Seal (1)
Stationary Housing
Rotating Shaft
Kondisi Seal sebelum ber-operasi
Kondisi Seal sesudah ber-operasi
Soft Babbit Replaceable liner
Gas Flow
Labyrinth Seal (2)
Labyrinth
Seal
Seal Oil dan Buffer Gas Sistem
Fungsi :“Sebagai sealing antara sistem oil dan sistem gas”
Seal Oil : Mencegah masuknya gas ke sistem oil
Buffer Gas : Mencegah masuknya seal oil ke compressor casing
Seal Oil & Seal Buffer Gas
Seal Oil & Seal Buffer Gas (cont,d)
Buffer Gas DP
Seal Oil & Seal Buffer Gas (cont,d)
P = 55 psig
Lubricating Oil
P = P-suct+ 20 psi
Seal Oil
P-suct / P-dischGasdalam Compressor
DischargeSuction
Seal Oil dan Buffer Gas Drain
P = P-suct+ 15 psi
Buffer Gas
Buffer Gas SealBalance Piston Seal
(Discharge)
Komponen Seal oil System• Auxiliary Seal Oil Pump
– Start saat tekanan prelube > 6 psig
– Berhenti saat loading speed (90% NGP)
– Saat engine Shutdown, Start pada saat NGP < 90% , berhenti Pcasing < 4 psig
S-21
Komponen Seal oil System (1)
Main Seal Oil PumpMengambil alih Auxiliary Seal Oil Pump pada NGP > 90% 2000 rpm pada 100% NGP
Flow RegulatorMenjaga aliran seal oil konstan pada setiap tekanan
Komponen Seal oil System (2)
Differential Pressure RegulatorSeal Oil DP Regulator
Menjaga tekanan seal oil 20 psid di atas tekanan suction
Buffer Gas DP RegulatorMenjaga tekanan buffer gas 15 psid di atas tekanan suction
Tekanan acuan : Tekanan Suction atau Drain Cavity ( Seal Oil dan Buffer Gas Out )
Komponen Seal oil System (3)
Seal Oil INSeal Oil Return
Buffer Gas
Diaphragm
Seal Oil DP Regulator
Maximum Seal Oil Leakage
Komponen Seal oil System (3)
Seal Oil Separator / Trap
Memisahkan gas dari seal oil agar tidak masuk ke Lube Oil Tank
Meyakinkan seal oil tidak tertarik ke pipeline melalui booster compressor
Seal Oil kembali ke tank dibantu oleh tekanan gas di atasnya
High Pressure Oil Trap
Type Seal Oil Trap
Spring
Oil return port
Floater
Gas outSeal Oil & Gas Mixed
Oil out
Sistem Buffer GasInternalGas dari Balance Piston labyrinth seal (discharge) diregulasi tekananya, diinjeksikan sebagian ke suction bearing capsule
EksternalGas dari discharge elbow diregulasi tekanannya, diinjeksikan ke suction dan discharge bearing capsule
Sistem Buffer Gas-Internal
BG Reg.
To Suction Brg. Capsule
To Suction pipe
Sistem Buffer Gas-External
BG Reg
External Buffer Gas
sources
Buffer Gas DP Operating Range
Model No. Buffer Gas DP (psig)
Minimum Nominal Maximum
C-16 5 15 50
C-16H 5 15 50
C-160 5 15 50
C-28 5 15 50
C-30 5 15 50
Dry Seal SystemIn this system, separation of lube oil and process gas is accomplished by a series of seals, installed between
the inboard journal bearing and the impeller.
Buffer Gas• Buffer gas is injected between the primary seal and the labyrinth seal on the rotor hub, at pressure
above suction pressure.• The differential pressure and proportional flow path sizes causes most of the buffer gas flows across
labyrinth seal and back to suction chamber of the compressor.• The remaining small amount of buffer gas flows across primary seal and is vented from the seal
assembly through a fixed orifice and flame arrester to a safe area.• A secondary seal is installed adjacent to the primary seal, acting as a backup in the event of failure of
the primary seal.• Different pressure regulator maintain a differential of approximately 20 psi above suction pressure.
Buffer Air• The buffer air seal is a split-ring circumferential seal, adjacent to the inboard journal bearing of the
compressor rotor.• Air or Nitrogen is supplied to the seal at a regulated pressure. Small portion flows across the inner
seal seal and out the secondary seal vent. The balance of the buffer air flows across outer portion seal into lube oil drain (mixed with LO draining from journal bearing)
• Different pressure regulator maintain a differential of approximately 10 psi between seal inlet and the secondary seal vent port
Dry Seal SystemComponent Description
• Buffer Air DP Regulator– Normally open diaphragm and poppet type– Secondary vent pressure and spring act on the OPEN side of the valve diaphragm– Seal inlet pressure acts on the CLOSE side of the valve diaphragm– The opposing forces maintain equilibrium at the pre-adjusted set point of the valve
Normally 10 psid
• Buffer Air DP Transmitter– Connected between seal inlet and secondary seal vent line– Sends an electrical signal proportional to the pressure across the inboard buffer air seal
to the control system– If DP falls below 7 psi, and ALARM will be activated– If DP falls below 4 psi, a Fast stop SHUTDOWN will be initiated.
• Buffer Gas DP regulator– Normally open, Diaphragm and poppet type– Suction pressure and spring pressure acting on the OPEN side of the diaphragm– Buffer Gas inlet on the CLOSE side of the diaphragm– The valve is adjusted to balance the diaphragm at nominal pressure of 20 psid
Dry Seal System• Buffer Gas DP Transmitter
– Connected between suction (reference) line and the buffer gas seal inlet line– If DP falls below 7 psi, with engine speed at 90 % or higher– If DP falls below 4 psid, with engine speed at 90 % or higher
• Buffer Gas Filter DP Transmitter– Monitor DP filters, provides a proportional signal to control system
indicating filter condition– If DP exceeds 40 psid, ALARM signal will be initiated
• Buffer Gas Flow-Limiting Orifice– 0.295 size orifice, installed in the buffer gas IN line– Limits the flow of gas as the labyrinth seal wears and its clearances increases
• Buffer Gas Flow-Monitoring Orifice– 0.25 size orifice, installed in the primary seal vent line, to measure seal leakage flow
In the vent line
– A relief valve, connected in parallel with the orifice, is adjusted to open at 30 psid, provides an escape gas in the event of a serious failure of the primary seal. Reducing the possibility of ove-pressurizing the buffer air seal and contaminating the lube oil system with gas.
Dry Seal System• Primary Seal Vent Alarm and Shutdown Transducer
– Connected to the primary seal vent line– Provide signal to the control system representing the absolute pressure at the vent port– If the pressure at the vent line 12 psig, ALARM signal will be activated– If the pressure at the vent line 20 psig, SHUTDOWN signal will be activated
NOTEThe back pressure at the primary seal vent must not exceed 5 psig
A
S/D
S/D
A
A S/D
A
S/D
R
R
AIR / N2
BUFFER GAS
PRIMARY SEAL VENT
SECONDARY SEAL VENT
BALANCE PISTON
2nd seal Hi Flow Alarm switch
LO INLO IN
Balance Piston & Seal
• Balance piston adalah bagian dari rotor yang digunakan untuk mengurangi gaya axial
• Balance Piston ada pada sisi discharge, setelah internal staging yang terakhir
Balance Piston & Seal (1)
Balance Piston & Seal (2)
Balance Piston
Balance Piston & Seal (3)
PERFORMANCE
OFCENTRIFUGAL COMPRESSOR
Performance EvaluationPerformance EvaluationEvaluasi Penting karena :Evaluasi Penting karena :
Mengetahui existing Performance (Optimal atau Tidak)Mengetahui existing Performance (Optimal atau Tidak)Mengetahui Kondisi Kompressor (Fouling, excessive seal wear dll)Mengetahui Kondisi Kompressor (Fouling, excessive seal wear dll)Mengambil keputusan perlu atau tidak compressor cleaning atauMengambil keputusan perlu atau tidak compressor cleaning ataucompressor Recompressor Re--StagingStaging
Adapun Performance Evaluation meliputi :Adapun Performance Evaluation meliputi :-- Compressor TheoryCompressor Theory-- Physical Properties of GasPhysical Properties of Gas-- Head, Flow and EfficiencyHead, Flow and Efficiency-- Compressor Performance Curve / MapCompressor Performance Curve / Map-- Compressor Horse PowerCompressor Horse Power-- Performance Analysis and Their Problem A risePerformance Analysis and Their Problem A rise
Compressor Theory
• Persamaan Euleur
• Persamaan Bernouli
• Hukum-hukum Thermodinamika– Process Adiabatik / Isentropik – Process Polytropic
Energi Gas
• Terdiri dari : Head (tekanan) dan Flow
• Horse Power = Head X Flow
• Head adalah besaran enersi yang diberikan kepada gas untuk setiap satu besaran massa.
Gas Physical Properties
• Specific Gravity
• Ratio of Specific Heat
• Compressibility factor
Specific Gravity (s.g)• Adalah : Perbandingan molecular weight dari
gas mixture terhadap Molecular weight udara.
• Molecular weight udara = 28.964
Mol weight gas mixture• SG = ---------------------------------
28.964
Compressibility factor (Z)
• Adalah factor koreksi volume dari perhitungan gas ideal menjadi gas actual.
• Harga Z selalu < 1
Compressibility factor (Z)
Sample of Gas Analysis
Perhitungan SG
Compression Head
53.35 x Z av x k x T1 (k-1)/k
Head = ----------------------------------[ (P2/P1) - 1]
SG x (k-1)
Head = Ft. Lbs force / Lbs mass.
Z ave =Compressibility factor
k = Ratio of specific heat
T1 = Temperature gas suction (Deg R)
P1 = Pressure gas suction (psia)
P2 = Pressure gas discharge (psia)
SG = Specific Gravity gas
Horse Power Required
1.6417 x 0.001 x Head x Flow MMSCFD x SG
HP = ----------------------------------------------------------------
Efficiency
HP = Horse power yang dibutuhkan oleh
compressor yang tersedia pada shaft compressor.
Isentropic Efficiency
(k-1)/k
T1 [ (P2/P1) - 1 ]
Eff = -----------------------------------
T2 - T1
Compressor Curve / MapAda tiga macam Curve
– Dimensional Curve– Semi-Dimensional Curve– Head vs Capacity (Flow) Curve
Rule :The Head versus Capacity curve is the only curve necessary
Dimensional CurveUse for Bid evaluation
Pressure versus Standard FlowDetermines operating rangeBased on Constant Suction or Discharge PressureNo Longer of value after purchase decision
Can determine specific operating ConditionPower & Speed
Shape of curve very demendent on base conditionsSuction TemperatureSuction PressureDischarge PressureGas Composition
Semi-Dimensional CurveUse for Bid evaluation
Pressure Ratio versus Standard Flow divided by pressureDetermines operating rangeBased on Constant Suction or Discharge PressureNo Longer of value after purchase decision
Can determine specific operating ConditionPower & Speed
Shape of curve very demendent on base conditionsSuction TemperatureSuction PressureDischarge PressureGas Composition
Head versus Capacity CurveOnly affected slightly by changes in base
conditions– Suction and Discharge Temperature– Discharge Pressure– Gas Composition
Used to determine the condition of an operating compressor– Compare actual efficiency to nominal (curve)
efficiency– Compare actual speed to nominal (curve) speed
Performance Diagnostics Method
1. Actual versus Nominal Data• Actual
Speed MeasuredEfficiency Calculated (from measured data)
• NominalSpeed From Head – Capacity curveEfficiency From Head – Capacity curve
Performance Diagnostics Method2. Creates 9 possibilities
EFFICIENCY SPEED COMMENTS
OK OK Compressor probably OK
OK LOW Check speed, P1, P2, and SG measurement
OK HIGH Possible compressor damage
LOW OK Possible compressor damage, Check T1, 2
LOW LOW Data probably suspect, Check P1,2 and SG
LOW HIGH Possible comp. Damage. Check Flow measurement
HIGH OK Comp. Probably OK. Data possibly suspect. Check T1,2 measurement
HIGH LOW Comp. Probably OK. Data definitely suspect. Check T1,2 measurement
HIGH HIGH Comp. Probably OK. Data definitely suspect. Check T1,2 measurement
Yard Valve Sequence
Yard Valve Sequence
Yard Valve Sequence