LAPORAN PRAKTIKUM Gas Turbine Engine (Removal & Installation Engine Allison M250-250)
Dosen Pembimbing: Radi Suradi K, Dipl.Ing. M.Eng
Disusun oleh: Regina Dwi Maulida (151221024) Rhismansyah Adiguna Effendi (151221025) Rizal (151221026) Rizal Fadilah (151221027) Sandi Tresna Priandi (151221028) Sulaiman (151221029) Vicka Berliseptiany (151221030)
PROGRAM STUDI TEKNIK AERONAUTIKA JURUSAN TEKNIK MESIN POLITEKNIK NEGERI BANDUNG 2018
DAFTAR ISI
DAFTAR ISI............................................................................................................................ 1 DAFTAR GAMBAR .................................................................
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BAB I PENDAHULUAN ........................................................................................................ 2 I. 1
LATAR BELAKANG ............................................................................................. 2
I. 2
TUJUAN PRAKTIKUM ........................................................................................ 2
I. 3
BATASAN MASALAH .......................................................................................... 3
BAB II TINJAUAN PRAKTIKUM ...................................................................................... 4 II.1
ENGINE HELIKOPTER ....................................................................................... 4
II.2
SA 3180 ALLOUETTE ASTAZOU ENGINE DATA ......................................... 5
1.
ENGINE CONSTRUCTION ................................................................................. 5
2.
ENGINE OUTPUT PERFORMANCE ................................................................. 5
BAB III HASIL PRAKTIKUM ............................................................................................. 6 BAB IV KESIMPULAN ....................................................................................................... 17 REFERENSI .......................................................................................................................... 18 LAMPIRAN........................................................................................................................... 19 A.
DOKUMEN PENDUKUNG..................................................................................... 19
B.
DOKUMENTASI KEGIATAN PRAKTIKUM ..................................................... 26
1
BAB I PENDAHULUAN I. 1
LATAR BELAKANG
Helikopter adalah pesawat udara yang tergolong pada jenis sayap putar (rotary wing) dimana helikopter memiliki sayap yang berputar atau baling – baling untuk menghasilkan gaya angkat (lift). Adanya perbedaan sayap helikopter yang merupakan baling – baling dengan sayap pesawat yang bersayap tetap (fixed wing), tentunya akan terlihat pada penggunaan komponen – komponen utama dan prinsip kerja dari helikopter dan pesawat fixed wing. Perbedaan yang sangat terlihat salah satunya adalah pada sumber tenaga penggerak atau engine yang digunakan. Pada laporan praktikum ini penulis berusaha untuk membahas mengenai engine yang digunakan pada helikopter dengan melakukan pengamatan pada salah satu contoh helikopter yaitu SA 3180 Allouette Astazou yang menggunakan engine Allison M250 seri C250. Pengamatan yang dilakukan oleh penulis yaitu kondisi engine secara keseluruhan, dari hasil pengamatan ditemukan bahwa engine mengalami damage berupa erosi dan korosi, maka dari itu engine perlu di-remove untuk dilakukan proses maintenance. Akibat dari proses maintenance, nilai jam terbang dan cycle dari engine mengalami perubahan.
I. 2
TUJUAN PRAKTIKUM
Tujuan diadakannya praktikum ini antara lain, 1. Memahami jenis kerusakan/damage yang ditemukan pada engine allison pada helikopter alouette. 2. Memahami prosedur kerja removal dan installation engine allison pada helikopter alouette. 3. Memahami dan bisa menghitung perubahan jam terbang dan cycle engine setelah dilakukan proses maintenance.
2
I. 3
BATASAN MASALAH
Batasan masalah pada pelaksanaan praktikum ini adalah, 1.
Praktikum dilakukan pada helikopter SA 3180 Alouette Astazou.
2.
Praktikum dilakukan pada engine Allison M250 seri C250.
3.
Jenis praktikum yang dilakukan hanya removal dan installation.
4.
Perubahan jam terbang yang dihitung adalah TSN, TSO dan CSN.
3
BAB II TINJAUAN PRAKTIKUM II.1
ENGINE HELIKOPTER
Engine adalah salah satu komponen penting sebuah pesawat yang berfungsi sebagai penghasil tenaga dengan berbagai macam penggunaan sesuai dengan jenis pesawat atau ukuran pesawat tersebut. Penggunaan yang diaplikasikan pada berbagai macam pesawat udara antara lain, sebagai penghasil gaya dorong (untukengine dengan jenis turbojet dan turbofan) dan sebagai tenaga penggerak propeller atau rotor (untuk engine dengan jenis turboprop, turboshaft dan piston engine). Helikopter alouette astazou menggunakan engine turbine berjenis turboshaft , engine turboshaft ini tidak menghasilkan langsung gaya dorong (thrust) ataupun gaya angkat (lift) yang membuat helikopter tersebut bergerak. Engine turboshaft pada helikopter menggerakkan shaft (poros) yang ditransmisikan melalui reduction gearbox untuk mengerakkan main rotor dan tail rotor.
Gambar 1. I lustrasi F ree-Turbine
Berbeda dengan engine turbine lainnya engine turboshaft yang digunakan pada helikopter sebagai penghasil tenaga untuk memutarkan shaft , pada bagian turbine terdapat bagian atau stage turbine khusus yang langsung ditransmisikan pada reduction gearbox menjadi tenaga keluaran untuk menggerakkan shaft. Stage khusus ini disebut
4
free-turbine, disebut free-turbine karena pada stage ini turbine tidak terhubung untuk menggerakkan compressor yang berada di engine guna mengkompresi udara untuk proses pembakaran. Sehingga dihasilkanlah tenaga yang cukup besar untuk menggerakkan shaft yang nantinya ditransmisikan untuk menggerakkan main rotor dan tail rotor . II.2
SA 3180 ALLOUETTE ASTAZOU ENGINE DATA
1.
ENGINE CONSTRUCTION
Nama engine
: Allison 250
Compressor
: 2 Stage Axial
Combustion chamber : Single Can with Single Burner Turbine 2.
: 2 Stage Axial with 5.8:1 reduction gear
ENGINE OUTPUT PERFORMANCE
Design power output Design speeds: Gas producer Power turbine Power output shaft Maximum measured gas temperature –– stabilized (TOT) Dimensions: Length Height Width Engine weight: Dry
Maximum oil consumption
400 shp (298 kW) 100% (50,970 rpm) 100% (33,290 rpm) 100% 6,016 rpm 1490°F (810°C)
40.8 in. (1036 mm) 23.2 in. (589 mm) 19.1 in. (485 mm) 155 lb (70 kg) (Bendix) 158 lb (72 kg) 0.05 US gallons per hour or 1 qt in 5 hours (0.9 liter in 5 hours)
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BAB III HASIL PRAKTIKUM Unscheduled maintenance A. Special inspection due to erosion and Corrosion Inspection
Special inspections are required when the engine has been subjected to abnormal operating conditions, when engine damage is suspected, or when associated parts are removed from the engine. In table 604, special inspection must be do when Operation in erosive environment If the aircraft is frequently subjected to sand or dust ingestion or operated in a corrosive environment (salt laden or other chemically laden atmosphere such as pesticides, herbicides, sulphur, industrial pollutants, etc.), inspect compressor blades, vanes, and case plastic coating for erosion or corrosion damage. Engines operated in a corrosive environment should be subjected to daily fresh water compressor rinses. NOTE: If the aircraft is subjected to sand or dust ingestion, periodic compressor erosion inspection is recommended. The frequency of the inspection should be based on the degree of ingestion and condition of the compressor at the last inspection. The need for more frequent compressor rinse may also be indicated. NOTE: See CSL – 1135 for instructions on suggested contamination removal using water only and for maps of operating areas with salt laden air. B. Water Rinse Procedure:
Engines subjected to salt water contamination or other chemically laden atmosphere (industrial pollutants, sulfur laden atmosphere, pesticides, herbicides, etc.) shall undergo water rinsing after shutdown following the last flight of the day. Perform the rinse operation as soon as practical after flight, but not before the engine has cooled to near ambient temperature. NOTE: Operators should be aware that salt laden air may be encountered for 75--150 miles inland under certain weather conditions. All islands are considered a severe area. If there is any doubt about the conditions in which your engines are operated, the engines should be given a daily water rinse. Acceptable water will not damage the engine but salt and chemicals will. In our case, the helicopter fly around in Indonesia which is from the Corrosion Severity Maps of the World Indonesia included in severe corrosion area. See the maps below:
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(1) Precautions
CAUTION: BE SURE THE IGNITION CIRCUIT BREAKER IS PULLED TO PREVENT IGNITION DURING THE RINSE CYCLE. CAUTION: THE PC TUBE FROM THE SCROLL TO THE PC FILTER SHOULD NOT BE REMOVED WHEN PERFORMING THE DAILY WATER RINSE. (a) Do not perform the rinse procedure while the engine is operating at idle speed as damage to the compressor will result. (b) N1 speed must not exceed 10% rpm during water spray injection. (c) Use the highest quality water available, distilled or demineralized water is recommended.
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NOTE: Use of water not meeting electrical conductivity of 20 micromhos per centimeter maximum will require the engine to be inspected per Rolls-Royce CSL 205 HOT CORROSION -- SULFIDATION. Operation in erosive environment (d) Do not spray water into a hot engine. The engine temperature is
satisfactory for water rinse when the bare hand can be placed on the outer combustion case without discomfort. (e) Avoid conditions which would allow the rinse water to freeze. NOTE: Methyl alcohol may be added to the water to prevent freezing during water rinse in below freezing weather. Mix one part methyl alcohol to one part water. This mixture prevents freezing down to --40°C (--40°F). The methyl alcohol shall contain methanol in concentrations not less than 99.85% by volume. (f) Do not inject a solid stream of water into the engine. Use a nozzle which provides a diffused spray pattern. (g) A conventional nozzle meeting the flow requirements of para 2, this section, may be used. Center the spray around the bullet nose of the inlet to ensure that all of the spray is injected into the engine. Spray a minimum of one quart into the compressor. (2) Materials and Equipment
(a) The highest quality water available must be used. Distilled or demineralized water is recommended. The most rapid and economical means to assess water quality is by measuring electrical conductivity. Control of electrical conductivity to a specific low level will automatically yield a low level of chlorides, sulfates, sodium, and other elements. Distilled or demineralized water with a maximum electrical conductivity of 20 micromhos per centimeter is recommended. NOTE: Most water deionizing equipment has the capability to determine electrical conductivity. Commercially purchased deionized/demineralized water conductivity information should be requested from the vendor. Should the electrical conductivity of the water not be known, the use of distilled or demineralized water is preferred. However, if water of unknown electrical conductivity is utilized, or if the water does not meet the maximum electrical conductivity of 20 micromhos per centimeter, then the engine must be inspected per CSL 205 “HOT CORROSION – SULFIDATION” (b) Portable equipment such as a clean garden sprayer or fire extinguisher which can be pressurized to obtain the required flow rate is recommended for water rinse. To provide capability for rinse with either portable equipment or a water
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supply system, a nozzle capable of flowing the recommended rate at about 55 psig (379 kPa) is desired. (c) The spray nozzle shall provide a diffused spray of water at a flow rate of one quart (1 liter) in nine to eleven seconds at the pressure conditions used during compressor rinse. The nozzle should b e sized to provide the proper flow rate at the average pressure maintained during each rinse cycle. NOTE: Test for proper water flow at the pressure to be used by placing the nozzle in a large container so that no water can splash out. Time the flow for 10 seconds and measure the quantity collected. Proper nozzle size for the pressure used should accumulate 1 to 1--1.125 quarts (0.95 to 1.06 liters). Adjust nozzle size as necessary to meet the specified flow limits. (d) A quick opening valve shall be installed in the supply tube as close to the nozzle as practical. (3) Spray application:
(a) Retain/select anti--ice valve in the “off” position. (b) Pull the engine ignition circuit breaker. (c) Series I and II engines: Block the bleed valve in the closed position using the wedge in compressor cleaning protector kit (6886204) (Ref. Fig. 1). It is not necessary to disconnect any lines. (d) Series III and IV engines: As a customer option, the bleed valve may be open or closed during the water rinse procedure. If it is to be closed, use the following procedure: 1. On double--plumbed bleed valves (23003106), remove the AN 929 cap from the tee--fitting at the bleed valve control solenoid. (Ref. Fig. 2). On single — plumbed bleed valves (prior to 23003106), remove the plug covering the Pc inlet port and insert an AN 815 union in the opening. (Ref. Fig. 3.) 2. Close the double--plumbed bleed valve by applying shop air at no more than 100 psi (689 kPa) to the tee--fitting. Close the single--plumbed bleed valve by applying the shop air to the union installed in the Pc inlet port. NOTE: Some aircraft manufacturers provide an airframe mounted air fitting to assist in pressurizing the bleed valve for the compressor rinse. If shop air is not available for bleed valve pressurization, and you want to close the bleed valve, the bleed valve must be removed and blanking plate fabricated and installed in its place prior to rinsing the compressor. CAUTION: TO PREVENT POSSIBLE BLADE DAMAGE AND TO ASSURE ADEQUATE RINSE AT THE BASE OF THE BLADES, N1 9
MUST NOT EXCEED 10% RPM. IF N1 RPM REACHES 10%, RELEASE THE STARTER AND CONTINUE THE WATER SPRAY. PERMIT N1 RPM TO REDUCE TO APPROXIMATELY 5% AND THEN REENERGIZE THE STARTER TO OBTAIN A FULL TEN SECONDS OF ENGINE ROTATION WHILE WATER IS SPRAYED INTO THE COMPRESSOR. CAUTION: NEVER PERFORM THE WATER RINSE PROCEDURE WHILE THE ENGINE IS OPERATING; THE COMPRESSOR IMPELLER WILL BE DAMAGED. A MOTORIZED RINSE PROCEDURE UTILIZING THE STARTER WITH N1 SPEED BELOW 10% IS THE ONLY AUTHORIZED PROCEDURE FOR THE MODEL 250--C28 OR --C30 SERIES ENGINE. (e) Spray water into the compressor inlet for 10 seconds while the engine is being motored with the starter. Start the water injection three seconds prior to starter engagement. The three second delay will reduce the tendency of the engine to accelerate above 10% rpm. The spray must flow the water as close to the bullet nose of the compressor inlet as possible to ensure that all of the spray is injected into the engine. Do not flood the engine prior to starter engagement. NOTE: Observe engine speed during the 10 second rinsing operation. The engine rpm will generally stagnate at or just below 10%; but when using a fully charged battery or an A.P.U., the rpm may tend to exceed 10%. (f) Continue injection of water spray during coast down until N1 stops, this improves the rinse of the base of the blades. Do not continue spray after engine stops. (g) Allow engine to drain. Combustion drain valves may be removed to improve rapid draining of the turbine. (h) Restore engine to operating configuration: 1. On Series I and II, remove the wedge from the bleed valve. 2. On Series III and IV, remove any installed fitting. Reinstall any removed caps or plugs as may be required (if removed). 3. Reinstall the combustion drain valves (and plumbing) if previously removed. (i) Within 15 minutes of the water rinse, operate the engine at idle for five minutes to purge and evaporate all residual water (actuate anti--icing system for one minute). NOTE: If exposure to excessive salt or other corrosive media has occurred, a repeat to the rinse procedure may be necessary.
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Alat Yang Digunakan:
Open Wrench 10 mm, 9 mm, 7/16 inch dan 5/8 inch.
Twister
Safety Wire
Work Stair
Crane
11
Coverall
Safety Shoes
Safety Glasses
12
TSN and TSO Installed : 20 November 2016
Removed 21 November 2017
TSN Pesawat : 21.000
TSN Pesawat : 22.100
TSN Engine
:
6.000
TSN Engine
:
7.100
CSN Engine :
8.000
CSN Engine :
9.100
TSO Engine :
1.600
TSO Engine :
2.700
TBO = 3600 Rata-rata terbang/hari
= 3 jam
Rata-rata cycle/hari
= 3 cycle
Rata-rata Estimasi Terbang = 60 satuan menit perhari TSN = Rata-rata terbang x hari selama setahun 3x365= 1095 TSO = Rata-rata terbang x hari selama setahun 3x365= 1095 CSN = Rata-rata Cycle x hari selama setahun 3x365= 1095 Rata-rata terbang/Rata-rata Cycle = 3 jam = 180 / 3
= 60 satuan menit
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Wheel turbine Allison 250
14
15
Ketentuan Manual TSN 1st-Stage Wheel TSN 2st-Stage Wheel TSN 3st-Stage Wheel TSN 4st-Stage Wheel
1775 1775 4550 4550
stage Wheel Turbin
sisa umur
Overhaul
1
0
( 4x ganti)
2
0
( 4x ganti)
3
2550
( 1x ganti)
4
2550
( 1x ganti)
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BAB IV KESIMPULAN
Helikopter SA 3180 Alouette Astazou II merupakan helikopter konfensional bermesin turboshaft pertama didunia. Helikopter ini didukung oleh mesin berjenis mesin turbin gas bertipe mesin turboshaft . Dimana turboshaft memiliki perbedaan dengan turbojet . Mesin turboshaft memliki hasil output yang digunakan untuk memutar poros yang nantinya akan digunakan untuk memutar main rotor pada helikopter. Berbeda dengan mesin turbojet , output dari engine yang dihasilkan akan memberikan gaya dorong dan tidak akan memutar shaft untuk memutar rotor . Turbin yang digerakan udara panas pun digunakan untuk memutar kembali kompresor. Pada engine Allison M250-250 terdapat damage berupa korosi dan erosi yang menyebabkan engine harus di-remove dan di-install kembali sebagai salahsatu proses maintenance. Setelah dilakukan remove&installation, engine mengalami perubahan jam terbang yaitu: TSN Pesawat 22.100, TSN Engine 7.100, CSN Engine 9.100, TSO Engine 2.700, dengan rata-rata terbang/Rata-rata Cycle 60 Menit.
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REFERENSI
B, A. (2017, January 7). Alouette: Artouste versus Astazou. Retrieved from What's Occur: http://occurs.lineum.org.uk/index.php?pages/Alouette%3A-Artousteversus-Astazou NATIONAL AERONAUTIC AND SPACE ADMINISTRATION. (2017, January 6). Nozzles. Retrieved from NATIONAL AERONAUTIC AND SPACE ADMINISTRATION: https://www.grc.nasa.gov/www/k12/airplane/nozzle.html The Turbomeca Astazou Aircraft Engine. (2017, January 7). Retrieved from Air Power World: http://www.airpowerworld.info/aircraft-enginemanufacturers/turbomeca-astazou.htm Turboméca. (1970). Engine Maintenance Manual, Turboméca Astazou II . Paris. UNITED STATES DEPARTMENT OF TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION. (2012). AVIATION MAINTENANCE TECHNICIAN HANDBOOK-POWERPLANT, Vol 1. Oklahoma city: United States Department of Transportation, Federal Aviation Administration. Wikipedia Indonesia. (2017, January 6). Mesin Turboshaft . Retrieved from Wikipedia Indonesia: https://id.wikipedia.org/wiki/Mesin_Turboshaft
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LAMPIRAN
A.
DOKUMEN PENDUKUNG
19
20
21
22
23
24
25
B.
DOKUMENTASI KEGIATAN PRAKTIKUM
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