Variasi Model Pembebanan Memberikan Pengaruh Signifikan terhadap Stabilitas Kapal Ikan GT

Sebanyak 31% dari total kecelakaan kapal yang terjadi sepanjang tahun 2018 sampai 2020 didominasi dan dialami oleh kapal penangkap ikan. Kecelakaan tersebut diakibatkan oleh buruknya stabilitas dan kemampuan kapal untuk menghadapi cuaca. Stabilitas merupakan salah satu aspek penting dalam keselamatan dan kelaik lautan dari suatu kapal. Maka dalam penelitian ini bertujuan untuk menganalisis dan mengevaluasi stabilitas kapal ikan tradisional, khususnya kapal ikan tradisional Madura. Dari hasil penelitian didapatkan bahwa stabilitas kapal di tiap kondisi pembebanan sudah memenuhi kriteria rules BKI (VOL 1) Domestic Ship sec 2.K. Part 4.1 dan ketentuan kriteria cuaca Guidelines on Intact Stability (Pt.6, Vol.3) Sec.2.C. yaitu, minimum nilai GM = 0,35 m, angle of steady heel tidak boleh lebih dari 16 deg, angle of steady heel / deck edge immersion tidak boleh lebih dari 80%, area1 / area2 tidak boleh kurang dari 100

ESTIMASI PELUANG TUBRUKAN KAPAL DENGAN METODE MINIMUM DISTANCE TO COLLISION (MDTC), STUDI KASUS : ALUR PELAYARAN BARAT SURABAYA

Tahun 2013, tercatat kepadatan lalu lintas kapal di Selat Madura mencapai 43.000 ship calls. Jumlah tersebut dirasa telah melebihi kapasitas daya dukung alur Selat Madura yang hanya 27.000 kapal per tahun (Kabar Bisnis, 2014). Dengan adanya rencana pengembangan infrastruktur di sekitar pelabuhan, keberadaan instalasi laut seperti platform, pipa dan kabel bawah laut di sekitar alur pelayaran, menyebabkan kepadatan Selat Madura semakin sulit diurai. Sehingga penting untuk dilakukan perhitungan probability of maritime accidents karena tingginya potensi hazard di lokasi tersebut, salah satunya adalah tubrukan kapal. Kondisi alur pelayaran yang terbatas dan tidak sebanding dengan jumlah kapal yang melintas menyebabkan terjadinya tubrukan kapal. Kerugian yang dialami akibat kejadian tubrukan kapal sangat besar, seperti hilangnya nyawa, kerugian lingkungan bila tubrukan menyebabkan tumpahan minyak, kerusakan fisik kapal serta kerugian ekonomi akibat kerusakan pada muatan. Melalui penelitian yang dilakukan, untuk mendapatkan nilai estimasi peluang tubrukan kapal dengan metode Minimum Distance to Collision (MDTC) (Montewka, 2011) didapatkan nilai peluang tubrukan kapal tertinggi berada di daerah inner channel pada spot 19000-30000 secara head on sejumlah 2.138 accidents/year dan peluang tubrukan terendah adalah tubrukan secara overtaking pada outer channel spot 13000-19000 sejumlah 0.086 accidents/year. Sedangkan dengan Traffic Based Model (Kristiansen, 2005) nilai peluang tubrukan kapal tertinggi berada di daerah inner channel pada spot 19000-30000 secara head on sejumlah 1.151 accidents/year dan peluang tubrukan terendah adalah tubrukan secara overtaking pada outer channel spot 38000-43000 sejumlah 0.130 accidents/year, diharapkan tubrukan kapal dapat dicegah sehingga frekuensi kecelakaan bisa lebih diminimalkan di daerah alur pelayaran barat Selat Madura, dimana sering terjadi kecelakaan kapal

Desain Dan Analisis Kekuatan Struktur Kontruksi Kapal Patroli 13 Meter Menggunakan Finite Element Method (FEM)

In the process of maintaining security and maintenance of the approach lightingsystem (ALS) at the airport area in Natuna which was built on the Natuna coast. So weneed a patrol boat that can meet the criteria in terms of the strength of the ship's structureto maneuver properly and accept internal and external loads. Structural capabilities thatare sufficiently safe are permitted according to BKI rules for ships made of fiberglassreinforced plastic. Case of slamming loading, it will be analyzed whether it is sufficientlysafe in terms of the strength of the construction structure on the 13-meter patrol boat thatloading may occur due to ship operations in the area around the airport. The initialcalculation is to calculate the scantling with a scantling weight of 2,226 tons and then drawthe construction in accordance with the lines plan and general arrangement of the 13 meterpatrol boat. Followed by the provision of a static load from slamming loading of 15,237KPa when the ship is at full speed of 20 knots to find out the response from the ship'sconstruction made of FRP. The value analyzed is the maximum stress (von mises) using theFinite Element Method (FEM) with static structural analysis and slamming loading in theform of pressure on the software as the method chosen in this study. Then raises the stressvalue in the ANSYS software, the maximum stress value that occurs in the construction is13.808 MPa and from this maximum stress value the safety factor value can be calculatedto find out how safe the ship's construction is if it is given a slamming load on the ship. Thesafety factor value in this study is 7,097. From the value of the safety factor it is knownthat the ship is still able to accept slamming loads at full speed

PERENCANAAN PERAWATAN IMPELLER DAN SHAFT FRESH WATER PUMP DENGAN METODE PREDICTIVE MAINTENANCE

A maritime transportation based company used corrective maintenance on these two component,impeller and shaft of fresh water pump inside their ship’s water cooling system. While using correctivemaintenance, these two components are getting maintained when its already in worse condition and made thesystem down. Therefore, a reliability analysis is performed using predictive method to predict when will these twocomponent would break down and then scheduled to fix based on MTTF value of component. Then, the systemwould run without getting disrupted because of the unit’s downtime

Analisa Tahanan Kapal Personal Boat di Selat Bengkalis Dengan Metode Numerik dan Pendekatan Empirik

Kabupaten Bengkalis merupakan salah satu daerah yang terletak di Provinsi Riau dengan luas wilayah mencapai 8.403,28 km2, yang terdiri dari 24 pulau disekitarnya. Dua pulau besar yakni Pulau Rupat dan Pulau Bengkalis. Dengan karakteristik wilayah berupa pulau-pulau yang dikelilingi oleh sungai-sungai kecil, membuat warga memanfaatkan sampan sebagai salah satu moda transportasi umum dari suatu pulau ke pulau lainnya.  Untuk mengakomodir kebutuhan warga akan moda transportasi air yang aman untuk penyeberangan antar pulau, maka dibuatlah personal boat dengan kapasitas penumpang 4 orang yang memiliki ukuran LPP = 4,800 meter, B = 1,900 meter, H = 0,800 meter, T = 0,200 meter dan Vs=20 knot. Kapal cepat jenis katamaran ini diharapkan mampu memenuhi kebutuhan warga di sekitar Bengkalis, terutama di selat Bengkalis dan sei Pakning. Dalam penelitian ini, perhitungan tahanan kapal dilakukan dengan menggunakan metode numerik (software maxsurf) yang dibandingkan dengan pendekatan empirik, yaitu metode savitsky. Hasil yang didapatkan dari penelitian ini adalah tahanan kapal yang didesain memiliki performa yang baik. Hal ini dibuktikan dengan nilai tahanan total yang didapat yaitu sebesar 0,9 kN pada perhitungan dengan metode numerik dan 1,033 kN melalui perhitungan pendekatan empirik, dengan selisih 0,133 % sehingga hasil perhitungan dapat diterima

Pengaruh Penambahan Becker Mewis Duct pada Perfoma Propeller B-series

Pollution due to sea transportation is a problem that requires consistent handling. Recent years of research in the field of shipping have focused on reducing exhaust emissions by increasing fuel efficiency and decarbonization. Decarbonization in the shipping industry can be achieved by using energy saving devices to reduce fuel consumption. The Energy Saving Device commonly used in the shipping world is the Becker-Mewis duct (BMD). This study used a variation of the NACA profile on the Becker-Mewis duct fin. The CFD (Computational Fluid Dynamics) method is used to analyze the thrust coefficient and torque coefficient. Becker-Mewis duct was added to increase thrust and torque values. From the results of the analysis that has been carried out without variations from NACA, the thrust coefficient is 0.1526, the torque coefficient is 0.0162 and the efficiency is 0.5261. With the NACA 4412 variation, it has a thrust coefficient of 0.2579, a torque coefficient of 0.0252 and an efficiency of 0.5728. The NACA 4415 variation has a thrust coefficient of 0.2663, a torque coefficient of 0.0260 and an efficiency of 0.5743. With increased efficiency, the addition of Becker-Mewis duct can increase the performance of the propelle

Analisis Kekuatan dan Umur Kelelahan (Fatigue Life) Terhadap Pondasi Crane SWL 3,6 Ton pada Kapal LCT 31 Meter dengan Metode FEM (Finite Element Method)

– LCT is are transport vessels that can approach platforms and jetties. LCT vessels are equippedwith cranes to facilitate the delivery and transfer of accommodation needs on the ship. Therefore, it isnecessary to plan a crane foundation that can withstand the weight of the crane itself and the load liftedby the crane. The 31-meter LCT ship suffered damage to the crane foundation due to static loads, so it isnecessary to replace the new crane foundation. In this Final Project, we will analyze the strength andfatigue life of the 3.6 ton SWL crane foundation on a 31-meter LCT ship in order to minimize the risk ofwork accidents and estimate the fatigue life of the new crane foundation. To complete this Final Project,the method used is the finite element method by creating a model in AutoCAD 2016 software and analyzingit in the finite element method software. The results of the analysis show that the von mises stress thatoccurs is 124.53 MPa, while the maximum deflection that occurs is 1.54 mm and the safety factor valueis 1.525. These stresses and deflections are in accordance with BKI rules because they do not exceed theallowable stress of 190 MPa and the allowable deflection of 2.75 mm. And for the estimated fatigue lifeof the crane foundation of 28.62 years

Probability of Ship Collision Using Minimum Distance to Collision (MDTC); A Case Study of Surabaya West Access Channel (SWAC)

By 2013, it was recorded that the density of ship traffic in the Madura Strait reached 43.000 ship calls. This number is considered exceeding the existing capacity of Madura Strait which is only 27.000 ships per year (Kabar Bisnis, 2014). With the plan of port development around the area, the existence and future oil and gas platform installation, subsea gas pipeline and cables around the shipping channel, it is estimated that the density of Madura Strait is even more congested. It is important, therefore, to assess the probability of maritime accidents due to the high potential hazard in the area, and one of which is the ship collision. The existing shipping line condition in Madura Strait is limited (narrow) and not proportionate to the number of ships passing, and this could lead to ship collision. The loss caused by ship collision can be in many ways, such as loss of life, loss of environmental impact caused when oil spills, physical damage and economic loss as a result of the damage to the cargo. This research utilizes the Minimum Distance method to Collision (MDTC) to get an estimate value of the probability of ships collision (Montewka, 2011) and found the probabilities of ship collision as follows: in the inner channel at 19,000 to 30,000 spots in head-on collision 2,138 accidents/year and the lowest probabilities of ship collision is overtaking in the outer channel 0.086 at 13,000-19,000 spots accidents/year. While the Traffic Based Model (Kristiansen, 2005) found that the highest probability of ship collision in the inner channel at 19,000-30,000 spots in head-on 1,151 accidents / year and the lowest probabilities of ship collision is overtaking in the outer channel at 38,000-43,000 spots 0.130 accidents/year

Perencanaan Fire Fighting Foam Menggunakan Fluida Air dan Busa di Crude Oil Refinery

Crude Oil Refinery have various wells to obtain natural products in the form of crude oil in a large-scale production capacity. In oil well area there was an explosion caused by a lightning strike. This incident caused 7 production tanks caught fire. Handling to extinguish fires using fresh water through available fire extinguishing system. However, using fresh water in this system is less efficient. So, installation of foam fire fighting needed in the form of foam fluid to overcome in fire. Problems discussed in the research included designing a foam fire extinguisher installation. Calculate the amount of water and foam requirements, and the required pump capacity in the form of manual calculations and Pipe Flow Expert Software for comparison. Storage tank area has a surface area of 998.5 m². Minimum discharge time 65 minutes with minimum application speed 6.5 liters / minute. Crude oil storage have 3 hydrant pillars required with total head in this system is 51,05 meters. Total requirement for 3% foam solution is 20441.22 liters and 97% water requirement is 660932.78 liters. Calculation of pump power using Pipe Flow Expert software is 26,14 kW and manual calculation is 24,57 k

Desain Pipeline sebagai Media Transmisi Air pada Sistem Penyediaan Air Minum dari Sidoarjo hingga Gresik

Because population is increasing, water supply efforts will be made through the Drinking Water Supply System project. Therefore, the author will determine the media of water transmission with a debit 3020 l/s. Activities undertaken include designing pipelines and conducting hydraulic analysis. Results of the pipeline design given 3 segments aboveground, and after being calculated manually obtained the value of the maximum allowable pipe span is 3.5 meters for the pipe segment of KPA 66+050 with a longitudinal stress 20482.26 psi. Whereas in the pipe bridge segment of Gunungsari river and Kedurus river, the values of the maximum allowable pipe span is 3.3 meters with a longitudinal stress 15880.55 psi. Both of these longitudinal stress values still meet ASME B31.4 criteria, which is 28000 psi. From length of pipelines is 43523.5 meters, the resulting pump head is 122.9 meters, so that centrifugal pump type of Grundfos LS 400-350-397B-1F2BABBVP1 be selected. Based on hydraulics analysis using WaterCAD, obtained several variables such as flow supplied and flow demand values provided according to the provisions,then fluid velocity and pressure not exceed the limit. So based on this simulations, can be published that the pipeline planning of Drinking Water Supply System can work well