MECHANICAL
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Identifikasi Nilai Kekasaran Permukaan pada Pemesinan Paduan Magnesium
Get PDFThe using of magnesium alloy, as alternative to iron and steel, is becoming more popular in the manufacturing industries. Magnesium and its alloys were classified as lighter material and also available in a quite large quantity in this world. Some of machined componens, included automotive and aerospace componens were produced by cutting, which is known as machining process. The machining process done in several conditions doe to the pharamater or factor in machining process. The main factors in machining process are feed rate, cutting speed, machining condition and deep of cutting. The purpose of this research is to investigate the influence of cutting pharameter to the surface roughness of magnesium, when machined using milling process and supplied with cooling air from vortex tube cooler. Cutting pharameters used in this research are feed rate and cutting speed. Feed rate used was three levels, those are 0,15 mm/rev, 0,20 mm/rev, and 0,25 mm/rev. Cutting speed used also three levels, those are 23,18 m/min, 32,15 m/min and 42,7 m/min. Cooling air is released from vortex tube cooler with 15 oC of temperature. The result of this research is found that feed rate affected signicantly on surface roughness value. The surface roughness value increased with increasing of the feed rate level. An other han, the surface roughness value is also affected wear on the edge of the cutting tool. The wear on the cutting tool contributed to the changes of nose radius (become bigger), so increase the surface roughness value.Keywords: magnesium material, surface roughness, milling, cutting pharameter, cooling air
Pengaruh Variasi Normalitas NaOH pada Aktivasi Basa-Fisik Zeolit Pelet Perekat terhadap Prestasi Sepeda Motor Bensin 4-Langkah
Get PDF Natural zeolite is an alternative adsorbent. It needs firstly to be activated before using it as absorbent in order to get zeolite with high adsorption capacity. Previously, the use of pelletized zeolite activated by NaOH-physic and KOH-physic with varied normalities was only performed in a diesel engine to observe the engine performance.In this study there were two kinds of activation, that is chemical activation with NaOH activator variation on the normality of 0.25 N, 0.5 N, 0.75 N, and 1.0 N and physical activation with using a temperature of 220 °C for 2 hours. All are made in the form of adhesive zeolite pellets with a diameter of 10 mm and a thickness of 3 mm. From the test results and analysis showed that the use of chemically activated zeolite can improve the performance of 4-stroke petrol engine when compared without using zeolite. The best performance in this experiment obtained at the normality of 0,75 N. At road test, the pelletized zeolite can reduce the fuel consumption 23, 15 %, and 16,51 % at stationary test, and increase acceleration by 14,77 %.Keywords: zeolite adsorbent, variation of normality, activator of NaO
Pengaruh Perlakuan Alkali terhadap Kekuatan Tarik Serat Tandan Kosong Kelapa Sawit untuk Digunakan pada Komposit Serat Tkks
Get PDFEmpty Palm bunches (TKKS) is one of the solid waste generated by industrial palm oil plantations which contain lots of fiber and is one of the natural fiber source that the availability of abundant in Indonesia, especially in the province of Lampung. TKKS fiber can be used as an alternative amplifier to composite materials. This research was conducted to determine the influence of the chemical composition of TKKS fiber and know the tensile strength from TKKS fiber by doing a tensile test. Alkaline treatment NaOH 5% given to fiber to separate lignin and contaminants that contained in fiber so that it can increase the tensile strength fibers. TKKS fiber is obtained processing palm oil factory by the process of boiling oil palm fresh fruit bunches with a pressure of 2.5 until 3atm at temperature 1300C during 50 – 60 minutes. TKKS already parsed and then selected and measured with a length of 6 cm and a diameter of 0.2 mm. And then given an alkaline NaOH 5%. In this research on the treatment of alkaline NaOH 5% provided that treatment during 0 hours (without treatment), 2 hour, 4 hour, 6 hour. Results from the study found that fiber tensile strength affected by the chemical composition on the fiber, the higher the tensile strength of the cellulose content is increasingly high. Tensile strength in fiber with alkali treatment 2 hours of 0,03528 Mpa, 0,3996% strain, 0,088288 MPa elasticity modulus, if compared with fiber without alkali treatment of 0,018946 MPa tensile strength, 0,2056% strain, 0,092149 MPa elasticity modulus. This is due to the levels of cellulose fibers with alkali treatment 2 hours increased by 58,2808%, if compared with fiber without alkali treatment by 13,2848%.Keywords : TKKS fiber, the treatment of alkaline, chemical composition
Analisis Kecepatan dan Percepatan Gerak Robot Joules Menggunakan Metode Bilangan Kompleks
Get PDFIn general, kinematics analysis is done using graphics methods. But this method requires a substantial time in analyzing the kinematics of a mechanical system. With the development of technology, especially in the field of computers and informatics can facilitate the engineer in analyzing the kinematics. One method used with the aid of a computer program is the method of complex numbers. This study aims to analyze and compare the position, velocity, and acceleration results of the calculation method of complex numbers and methods of polygon graphics. The study was conducted on a robotic mechanical system, i.e. electric tandem bicycle partner named Robot Joules. Necessary data were analyzed using the method of complex numbers with the help of MATLAB program. Results of analysis using the method of complex numbers were compared with the results of analysis using the method of polygon graphics. For comparison, data input were made equal to the angular velocity rod 2 (ω2) of 10 rad/s and angular acceleration of rod 2 (α2) at 0 rad/s2 when bar 2 was at position angle 90 ° from the positive x-axis.
Key words: kinematics, robot joules, complex number
PENERAPAN PENILAIAN KEKASARAN PERMUKAAN (SURFACE ROUGHNESS ASSESSMENT) BERBASIS VISI PADA PROSES PEMBUBUTAN BAJA S45C
Get PDFKekasaran permukaan sebuah benda kerja memegang peranan penting terhadap kualitas suatu produk dalam proses pemesinan. Kekasaran permukaan diukur secara langsung menggunakan alat pengukur kekasaran permukaan. Cara lain adalah dengan pengukuran secara tidak langsung. Pada penelitian ini kekasaran permukaan diukur secara tidak langsung menggunakan teknik pengolahan citra dijital yang diaplikasikan pada proses pemesinan. Benda kerja (material baja S45C) dibubut menggunakan pahat jenis HSS dilakukan dengan memvariasikan beberapa kondisi pemotongan. Kecepatan potong (ν) yang digunakan adalah 53,38 m/menit, 78,50 m/menit, dan 119,32 m/menit. Pemakanan (f) yaitu 0,1 mm/rev, 0,15 mm/rev dan 0,25 mm/rev. Sedangkan kedalaman potong ditetapkan konstan yaitu 0,5 mm. Untuk melihat pengaruh nose radius (rε) terhadap kekasaran permukaan maka digunakan pahat yang mempunyai nose radius 0,4 mm dan 0,8 mm. Setelah selesai pemotongan akan dilakukan pengukuran kekasaran permukaan menggunakan surface tester. Kemudian dilanjutkan dengan pengambilan citra permukaan benda kerja menggunakan kamera dijital biasa. Citra ini kemudian diolah dan dianalisis profil intensitasnya dengan menggunakan perangkat lunak MATLAB 7.0. Dari pengukuran kekasaran permukaan menggunakan surface tester dan analisis citra dijital diperoleh perbandingan kekasaran permukaan beberapa spesimen. Selisih kekasaran permukaan hasil pengukuran dan analisis citra di antara 0,0018 – 0,0136 µm (sangat kecil). Kekasaran permukaan spesimen 3 (pada v=53,38 m/menit; f=0,1 mm/rev; rε=0,4 mm) hasil pengukuran adalah 3,22 (µm) sedangkan hasil analisis citra adalah 3,2336 (µm). Pada spesimen dengan nomor citra 6 (v=53,38 m/menit; f=0,1 mm/rev; rε=0,8 mm) kekasaran permukaan yang diperoleh dari pengukuran adalah 2,50 (µm) dan hasil analisis citra adalah 2,5044 (µm). Pada spesimen dengan nomor citra 13 (v=119,32 m/menit; f=0,25 mm/rev; rε=0,4 mm) kekasaran permukaan yang diperoleh dari pengukuran adalah 2,15 (µm) dan nilai kekasaran permukaan yang diperoleh dari hasil analisis citra adalah 2,1518 (µm). Spesimen dengan nomor citra 15 (v=119,32 m/menit; f=0,1 mm/rev; rε=0,4 mm) nilai kekasaran permukaan pengukuran adalah 2,86 (µm) dan nilai kekasaran permukaan yang diperoleh dari hasil analisis citra adalah 2,8524 (µm).Kata Kunci: kekasaran permukaan, pemrosesan citra dijital, machine visio
Konsep Proses Pemesinan Berkelanjutan
Get PDFMetal industrial machining usually strongth pressure from all sectors, ether raw material industries or user metal industries. Manufacturint process which offered to all sectors industries or companies that sustainable manufakturing consist of three main factor are efective cost, enviroment and social performance. Keywords: Sustainable, machining, social, enviroment, cost
Studi Kelayakan Pembangkit Listrik Tenaga Mikrohidro (PLTMH) pada sungai Arter Desa Hurun Kecamatan Padang Cermin Kabupaten Pesawaran Lampung
Get PDFElectricity is very important in human life. In Indonesia,electricity is a basic necessity for society and industry. Electrical energy supply in Indonesia is targeted to use the 5% comes from renewable energy, it has been included in the government regulation No. 3 of 2005. One of the power plants that are potentially is Micro Hydro Power (MHP), which is an implementation of the green energy initiative to encourage renewable energy step. If the MHP potential can be developed, then at least 12,000 MWh or 14% of Indonesia's total energy needs in 2005 are contributed by the MHP.The purpose of this final project: " Feasibility Study of micro hydro power plant (MHP) on arter river at hurun village Padang Cermin district Pesawaran region lampung " is to plan a hydroelectric small scale power plant that can be used and applied as a fulfillment of electrical energy in Indonesia, especially for people who can not enjoy electricity.The Procedures to obtaining data for Head cleaner using a plastic hose method and calculation method, so the net head of 11.15 m obtained. To determine the amount of water flow, the method used is the method of floating objects, as well as doing some calculations and obtained intake capacity of 66.7 l / s. And the resulting power of 5.10 Kw. From data result, turbine suitable types is crossflowtubine.Keywords: micro hydro power plant, water discharge, crossflow turbine
Rancang Bangun dan Unjuk Kerja Mesin Pengupas Kulit Biji Kopi Basah Sistem Rol Karet yang Produktif dan Ergonomik
Get PDFOne of the sub-process of coffee production is wet coffee processing. It is done to reduce the longer of drying time. So, it can minimize the growth of okhratoksin mushroom which can reduce the quality of coffee beans.There are some steps in doing this research, as follow; the first, choosing peeler knife by using weighted rating method the second, using ergonomic and anthropometry value tofind out dimension of the machine and choosing machine component. The third, attempting the machine performance. The fourth, calculating the breakeven point.The results showed that the specification machine with the length of wall is 420mm, the width of leg machines is 610 mm, the width of the machine is 490mm, high machine is 1200mm which is adjusted by measurement of Indonesian people anthropometric. Engine capacity with 600 kg / hour by moving the machine is an electric motor 1 phase and with rotation 1400 rpm. Transmission system used V-belt with diameter 32mm could connect reduction gear and transmitted sprocket to the cylinder axis cylinder axis peeler paring. Cylindrical roller paring used rubberroller (natural rubber, NR) with cylinder angle 450 and knife distance 7mm. Construction pattern of 70mmx70mmx7mm corner profile and casing used 7mm thickness plat with AISI steel 1045 and 1015. Breakeven value of Rp. 17.288 with production volume is 432kg.Keywords: Coffee, Ergonomic, Anthropometry, Natural Rubber, Steel AISI 1045 and 1015, Electrical motor
Makrostruktur dan Permukaan Patah dalam Uji Tarik Terhadap Perlakuan Panas pada Baja Karbon Rendah
Get PDFBaja karbon rendah kekuatan tinggi memperlihatkan kombinasi yang baik dalam kekuatan dan keuletan yang menarik perhatian dari berbagai penelitian. Tujuan dari kajian ini adalah untuk menyelidiki dan mempelajari dalam analisa mikrostruktur dan perilaku permukaan patah pada tensile properties dengan variasi temperatur pada baja dual phase. Sebelumnya,bahan telah di austenised pada temperatur 1000°C selama 30 menit dan diikuti dengan water quench untuk menghasilkan full martensit pada specimen. Kemudian bahan di anneal dalam kawasan interkritikal untuk mendapatkan 20, 50 dan 80% a’. Mikrostruktur baja dual phase setelah di annealing pada daerah dual phase dan water quenching, kekerasan baja dual phase ini meningkat dengan seiring meningkatnya vol.% martensit. Disamping itu, volume % martensit yang dihasilkan adalah lebih banyak dari pada ferit.Perubahan tegangan dan regangan lebih tinggi/meningkat dari pada kondisi 20% dan 50%. Dari kondisi pengujian tarik ini dapat disimpulkan bahwa dengan meningkatnya vol.% martensit maka tegangan maupun regangan bahan meningkat.Kekerasan bahan meningkat dengan meningkatnya %vol. martensit, ini terlihat bahwa kekerasan baja Cu adalah lebih tinggi dari baja base.Kata Kunci : Uji Tarik, Mikrostruktur, Baja Karbon Rendah dan Perlakuan
Analisa Perpindahan Panas Konveksi Aliran di Atas Permukaan Berkas Pipa: Sebuah Kajian Literatur
Get PDFHeat transfer in flow across bank of tubes is of particular importance in the design of heat exchangers. Heat exchangers are found in numerous industrial applications, such as steam generation in a boiler or air cooling in the coil of an air conditioner. The Zakauskas’s correlation from the experimental data is more popular method that used to design of cross flow of heat exchanger. However, due to optimization process and more efficiency, several empirical equations were generated through the analytical and CFD methods. Hence, this paper was intended to perform a comprehensive study to analyze the heat transfer calculation of cross flow heat exchanger by using several methods in which it has been reported. Among of four methods are analyzed, the analytic method, normalization equations from CFD and Grimison’s correlation have good agreement to used for design of cross flow heat exchanger with the compact and non-compact configuration, while correlation of Zakauskas is only suitable for non-compact configuration