Perancangan Spud Pada Dredger Barge 25 Meter

Operation of ships with special functions such as dredgers or commonly called Dredger Barge requires special support such as spuds. In addition to being able to replace anchors more effectively, it can also facilitate supporting vessels such as Anchor Handling Tug and ensure safety while operating. In this study planning and analysis needs to be done in order to estimate the reaction and the condition of the spud and the spud holder at the time of operation. The study approach uses Solidwork software to simulate the strength test of the material as well as the safety of the spud and the spud holder when receiving sea wave pressure, ocean currents and wind in extreme weather using Mild Steel (ASTM (S) A36) material. The results of the simulation of the strength and feasibility test of the spud and the spud holder were obtained with a von mises spud value of 0.0856 N / mm2 and a von mises value on the spud holder of 15.5 N/mm2 with the parameter value of the von mises spud and spud holder of 188 N / mm2. Furthermore, the simulation results of the shear stress value on the spud are 2.37x10-7 N/mm2 and the shear stress value on the spud holder is 3.32x10-5 N/mm2 with the parameter value of the spear shear stress and the spud holder of 141 N/mm2. Furthermore, the simulation results of the Deflection value for the spud is 0.00116 mm and the deflection value for the spud holder is 0.117 mm with the deflection spud parameter value of 80 mm, and the deflection parameter for the spud holder is 10 mm. The spud and spud holders in this design are feasible in production and have been guaranteed safety and feasibility by referring to the parameters according to the standards of the Bureau Veritas and American Institute of Steel Construction rulesPengoperasian kapal dengan fungsi khusus seperti kapal keruk atau biasa disebut Dredger Barge membutuhkan support khusus seperti spud. Selain dapat menggantikan jangkar yang lebih efektif juga dapat memudahkan kapal – kapal pendukung seperti Anchor Handling Tug dan menjamin keamanan saat beroperasi. Dalam studi ini peracangan dan analisa perlu dilakukan guna untuk memperkirakan reaksi serta kondisi spud dan spud holder pada saat operasi. Pendekatan studi menggunakan software Solidwork untuk melakukan simulasi uji kekuatan bahan serta keamanan spud dan spud holder ketika menerima tekanan gelombang laut, arus laut dan angin pada cuaca ekstrim dengan menggunakan material Mild Steel (ASTM(S) A36). Hasil simulasi uji kekuatan dan kelayakan spud dan spud holder di dapat dengan nilai von mises spud sebesar 0,0856 N/mm2 dan nilai von mises pada spud holder sebesar 15,5 N/mm2 dengan nilai parameter von mises spud dan spud holder sebesar 188 N/mm2. Selanjutnya hasil simulasi nilai shear stress pada spud yaitu sebesar 2,37x10-7 N/mm2 dan nilai shear stress pada spud holder sebesar 3,32x10-5 N/mm2 dengan nilai parameter shear stress spud dan spud holder sebesar 141 N/mm2. Selanjutnya hasil simulasi nilai Deflection pada spud yaitu sebesar 0,00116 mm dan nilai deflection pada spud holder sebesar 0,117 mm dengan nilai parameter deflection spud yaitu sebesar 80 mm, dan nilai parameter deflection spud holder sebesar 10 mm. Spud dan spud holder pada perancangan ini layak di produksi dan telah terjamin keselamatan dan kelayakan dengan mangacu parameter sesuai standar rules Bureau Veritas dan American Institute of Steel Construction

RANCANG BANGUN SIMULASI PERGERAKAN HIGH LIFT DEVICE PADA PESAWAT

The most high lift device modifying, for small airplanes and large, is the wing flap. Flaps can be installed on the leading edge or trailing edge (only for large airplane) aircraft. To make a simulator, the design and also the drive system are needed which will form the movement as in the real flap. As a driving mode, the system which designed on this flap simulator will use an electronic system. By using a servo motor as a drive and Arduino as a microcontroller that will be programmed according to the planned movement. The flap simulator can produce angles formed on servo motors such as 5º, 14º, 19º, 25º and  30º  its moving flaps on flap level 0, 1, 2, 3 and 4 in extend and retract movement modes.High lift device yang paling banyak digunakan pada pesawat kecil maupun pesawat besar adalah flap. Flap dapat dipasang pada leading edge maupun trailing edge (hanya untuk pesawat besar) pesawat.  Untuk membuat sebuah alat simulasi dibutuhkan rancang bangun dan juga sistem penggerak yang nantinya akan membentuk pergerakan seperti pada flap sesungguhnya. Sebagai mode penggerak, sistem yang dirancang pada alat simulasi flap ini akan menggunakan sistem elektronik yaitu motor servo yang akan dikendalikan oleh arduino. Sudut yang dibentuk oleh motor servo akan diberi penyesuaian terhadap sudut yang dibentuk oleh flap sesuai flap level. Alat simulasi flap ini dapat menghasilkan sudut yang dibentuk pada motor servo yaitu, 5º, 14º, 19º, 25º dan  30º  berhasil menggerakan flap pada flap level 0, 1, 2, 3 dan 4 baik pada mode pergerakan extend maupun retract

Thermodynamic Study on Decarbonization of Combined Cycle Power Plant

Integrating hydrogen firing and a carbon capture plant (CCP) into a natural gas combined cycle (NGCC) power plant is a promising strategy for reducing CO2. In this study, process simulation in Aspen PLUS of hydrogen co-firing in a 40 MW turbine gas combined cycle power plant was done at an identical gas turbine inlet temperature from 0%.cal to 30%.cal. The evaluated cases were hydrogen co-firing with CCP (H2 Co-firing + CCP) and hydrogen co-firing without CCP (H2 Co-firing). The results showed a 6% CO2 emission reduction per 5% increase in hydrogen, albeit with increased NOx emissions. H2 Co-firing experienced a decrease in net power with rising hydrogen co-firing, while H2 Co-firing + CCP saw an increase but remained below Case 2 due to the energy penalty from the carbon capture plant. The capital cost of H2 Co-firing + CCP exceeds that of H2 Co-firing due to CCP usage, impacting gross revenue. The sensitivity analysis indicated that the cost of hydrogen has higher sensitivity compared to the cost of CCP. Lowering hydrogen prices is recommended to effectively reduce CO2 emissions in NGCC

Rancang Bangun Alat Peraga Axial Flow Turbine Dengan Menggunakan Tenaga Electrical Sebagai Media Pembelajaran AMTO

Aircraft maintenance is very important in aviation safety. Therefore, ICAO (International Civil Aviation Organization) strictly regulates the people who can carry out the maintenance process. To be able to become a mechanic or engineer who maintains aircraft, it is necessary to have 3 stages, namely the basic certificate, type rating and AMEL (Aircraft Maintenance Engineering License). Currently in Indonesia there are only 13 AMTO (Aircraft Maintenance Training Organizations) that can issue the certificate. AMTO schools are limited because the facilities required by the authorities are very high and expensive. One of these facilities is a turboprop engine, a type of generator aircraft engine that uses a gas turbine to drive the propeller. The high cost of the training equipment facilities, which can reach hundreds of millions or even billions, gave rise to the idea to make a simple teaching aid about turboprop systems in general, namely the Axial Flow Turbine which applies the concept of a turboprop engine where the propeller can rotate due to mechanical motion from the gear that comes from the DC motor. Manufacture of Axial Flow Turbine components using lathe, and milling. The materials used are iron, plastic, and rubber. The Axial Flow Turbine can produce a maximum rpm of 200 rpm. After passing the maximum limit, the propeller's ability to rotate will decrease significantly. In the end, the Axial Flow Turbine teaching aid can be used as a learning medium, especially the turboprop system.Perawatan pesawat udara menjadi hal yang sangat penting dalam keselamatan penerbangan. Oleh karena itu, ICAO (International Civil Aviation Organization) mengatur secara ketat orang-orang yang dapat melakukan proses perawatan tersebut. Untuk dapat menjadi seorang mekanik atau engineer yang merawat pesawat udara perlu memiliki 3 tahapan yaitu basic certificate, type rating dan AMEL (Aircraft Maintenance Engineering License). Saat ini di Indonesia hanya ada 13 AMTO (Aircraft Maintenance Training Organization) yang dapat mengeluarkan sertifikat tersebut. Terbatasnya sekolah AMTO ini dikarenakan fasilitas yang disyaratkan oleh otoritas sangat tinggi dan berharga mahal. Salah satu alat fasilitas tersebut adalah mesin turboprop yaitu jenis mesin pesawat pembangkit yang menggunakan turbine gas untuk menggerakkan propeller. Mahalnya fasilitas alat training tersebut yang dapat mencapai ratusan juta bahkan miliaran memunculkan ide untuk membuat suatu alat peraga sederhana tentang sistem turboprop secara umum yaitu Axial Flow Turbine yang menerapkan konsep dari mesin turboprop yang dimana propeller dapat berputar akibat mechanical dari gear yang bergerak yang bersumber dari motor DC. Pembuatan komponen Axial Flow Turbine menggunakan lathe, dan milling. Adapun material yang digunakan adalah iron, plastic, dan rubber. Axial Flow Turbine dapat menghasilkan rpm maksimal sebesar 200 rpm. Setelah melewati batas maksimum maka kemampuan propeller utuk memutar akan menurun secara signifikan. Pada akhirnya alat peraga Axial Flow Turbine dapat digunakan sebagai media pembelajaran khususnya sistem turboprop

Ship Recycling Rig Hibiscus Ditinjau Dari Sistem Manajemen Daur Ulang Ramah Lingkungan

Ship recycling is considered the best alternative for disposing of obsolete ships. Ship recycling is an activity related to the ship recycling process, such as mooring/grounding of ships, taking, and repairing ship materials. The existence of the ship recycling industry in Indonesia includes Tanjung Jati (Madura), Cilincing (North Jakarta), Tenggamus (Lampung) and Tanjung Uncang (Batam). This study aims to determine the process of ship recycling hibiscus rigs carried out at PT. Batam Citra International, Tanjung Uncang, Batam City. Based on the results of the research conducted, it was found that the ship recycling rig hibiscus process was carried out using a cutting plan work plan, with the following stages: (1) Pre-arrival process at Sekupang anchorage, (2) Customs inspection at Sekupang Port, (3) Ship towed from Sekupang Harbor to PT. BES ship berths, (4) General inspection by PT. BCI and PT. BES, (5) Inspection by local environmental agencies, (6) Marking of IHM/dangerous substances on ships, (7) Transfer of hazardous and non-hazardous materials on board, (8) Transfer of oil and other flammable goods, (9) Engine room cleaning, (10) Ship recycling starts, (11) Monthly review of hazardous waste disposal, (12) Review of incidents that occurred and precautions taken, (13) Results of ship recycling, and finally, and (14) Compilation of ship recycling compliance reports.Ship recycling dianggap sebagai alternatif terbaik yang digunakan untuk membuang kapal yang telah usang. Ship recycling merupakan kegiatan yang berhubungan dengan proses daur ulang kapal yaitu seperti penambatan/pengandasan kapal, pengambilan dan perbaikan material kapal. Keberadaan industri ship recycling di Indonesia diantaranya terdapat di Tanjung Jati (Madura), Cilincing (Jakarta Utara), Tenggamus (Lampung) serta Tanjung Uncang (Batam). Penelitian ini bertujuan untuk mengetahui proses ship recycling rig hibiscus yang dilakukan di PT. Batam Citra International, Tanjung Uncang Kota Batam. Berdasarkan hasil penelitian yang dilakukan, diperoleh bahwa proses ship recycling rig hibiscus dilakukan menggunakan rencana kerja cutting plan, dengan tahapan sebagai berikut : (1) Proses pra–kedatangan di Sekupang anchorage, (2) Inspeksi bea cukai di Pelabuhan Sekupang, (3) Kapal ditarik dari Pelabuhan Sekupang ke dermaga PT. BES tempat berlabuh kapal, (4) Pemeriksaan umum oleh PT. BCI dan PT. BES, (5) Inspeksi badan lingkungan hidup lokal, (6) Penandaan IHM/ bahan berbahaya pada kapal, (7) Pemindahan bahan berbahaya maupun tidak berbahaya di dalam kapal, (8) Pemindahan Minyak dan barang yang mudah terbakar lainnya, (9) Pembersihan ruang mesin, (10) Ship recycling/ daur ulang kapal dimulai, (11) Tinjauan bulanan pembuangan limbah berbahaya, (12) Tinjauan insiden yang terjadi dan tindakan pencegahan yang diambil, (13) Hasil daur ulang kapal, dan yang terakhir, dan (14) Penyusunan laporan kepatuhan daur ulang kapal

Experimental Verification of Interfacial Strength Effect on the Mechanical Properties of Carbon Fiber-Epoxy Composite

The effects of carbon fiber–epoxy interfacial strength on the mechanical properties of the corresponding fiber-matrix composites are experimentally demonstrated in this work. Two composites containing different carbon fibers were tested: as-received fibers and fibers soaked in acetone to remove adhesive on their surfaces. The fiber surfaces were first characterized by scanning electron microscopy and time-of-flight secondary-ion mass spectrometry to verify removal of the adhesive. Further, single-fiber fragmentation tests were conducted to evaluate the fiber strength and the interfacial strength. The mechanical properties of the composites were evaluated via tensile testing under longitudinal and transverse loadings. The results show that interfacial strength does not decrease the mechanical properties of the composites under longitudinal loading. In contrast, under transverse loading, the interfacial strength significantly decreases the mechanical properties, specifically the ultimate tensile strength and toughness of the composites

New Method of Materials Flow Calculation for Double-String SLCI Type Cement Plant (Part 1: The Whole Clinker Plant)

Materials flow values are instrumental in many industries for controlling and simulating processes, designing new equipment as well as modifying existing plants. They are sometimes impossible to determine by direct measurement in an operating plant due to the very high temperatures. This study attempted to overcome the difficulties associated with this measurement by proposing a new method to calculate materials flow of a double-string suspension preheater type of cement plant with separate line and in-line calciners (SLC-I), with heat balance error less than 1%. This study was divided into two sequential parts, with the first part presented in this paper. The methodology of the first part was to solve the conservation law of the main clinker plant equipment, supported by Bogue’s equation, the heat of calcination, and the thermodynamic properties of the related materials. The least-square method was employed for solving the overdetermined system equations obtained in the second part. The results of the first part were: the ratio of heat formation to specific heat consumption was 52.13% (> 50%), and the gas exhausted from the plant yielded more than 117 MW heat equivalent, which can potentially be recovered for electricity production

New Method of Materials Flow Calculation for Double-String SLCI Type Cement Plant (Part 2: Suspension Preheater and Calciners)

In many industries, energy auditing is important as the basis for controlling processes and designing additional equipment or modifying an existing plant. However, it requires detailed data of the materials flow, which often cannot be determined easily by direct measurement due to high-temperature limitations. This paper presents the second part of an integrated study to perform energy auditing in a separate line and in-line calciners (SLC-I) type cement plant. The second part of this study, as presented in this paper, focused on the materials flow calculation for eight separate cyclones and two calciners. The least square method was employed for solving the obtained overdetermined system equations. Using the operation data from Part 1 of the study, calculation of the detailed materials flow in each cyclone was executed. The results showed that the separation efficiency of cyclones 1A, 2A, 3A, 4A and 1B, 2B, 3B, 4B was 93.86%, 89.80%, 84.41%, 81.98% and 93.96%, 88.70%, 88.53%, 80.72% respectively and the estimated calcination percentage of kiln feed coming out of the ILC and the SLC was 85.3% and 56.3%, respectively. These values are impossible to be measured directly in the cyclones and calciners during plant operation

Studi Kelayakan Pemindahan Area Pelayaran Batam Marine Ambulance (BMA) dari Pelabuhan Tanjung Punggur ke Area Sekupang Kota Batam

Pemindahan area pelayaran dilakukan guna memeperluas area pelayanan Batam Marine Ambulance (BMA). Kapal BMA merupakan kapal yang dibuat dengan kerjasama 3 instansi antara lain: Lembaga Amil Zakat (LAZ) Batam, Rumah Sakit Awal Bros Batam dan Politeknik Negeri Batam. Pemindahan area memerlukan kajian secara teknis baik terkait dengan kapal maupun tingkat kebutuhan transportasi yang digunakan. Lokasi pemindahan yang direncanakan adalah dari pelabuhan Tanjung Punggur menuju ke Pelabuhan Belakang Padang (Sekupang). Pemindahan ini diharapkan dapat meningkatkan taraf kesehatan masyarakat dan kemanfaatan dari BMA. Dari hasil kajian awal dan literatur didatapkan data bahwa, banyak masyarakat yang masih membutuhkan adanya sarana taransportasi yang tidak berbayar untuk melayani kesehatan. Hal ini terlihat dari banyaknya warga yang enggan untuk memeriksakan kesehatan karena kendala pada pembiayaan transportasi. Dari segi teknis terkait dengan kondisi perairan, area pelayaran lama dan area pelayaran yang direncanakan tidak memiliki perbedaan yang signifikan, sehingga untuk dampak lingkungan terhadap gerakan kapal dirasa tidak akan begitu jauh dan masih memiliki performa yang sama