ANALISIS PENGARUH VARIASI MATERIAL CORE TERHADAP KUALITAS NIPPLE

This study aims to determine the effect of variations in core material made of iron and resin sand on the Nepel Brass smelter on hardness, surface results of castings, shrinkage, density apparent, time, and cost. To find out which core material is more efficient for use in large quantities. The product material used is Brass in the form of Hose Nipple with a size of 1/5 x 5/8 inch. The average specimen weight in this study was 8.33 gr. From the research conducted, the differences were found, namely the hardness of the smelting process with the core material of iron castings and resin sand is 37.14 BH 5 / 250-25 and 30.94 BH 5/250-25. Material defects found are in iron castings specimens, namely rough surface defects, pinhole, scrabs, gas holes and air voids with 19 points of defect points and an area of ​​78 mm or 10.57% of the inside area of ​​the specimen. Likewise with resin sand-coated specimens experiencing defects of Coarse Surface, Needle Hole, Scrabs, Gas Hole, Air Cavity and sand inclusion / erosion hardness, with large numbers almost covering all parts of the specimen or 95.1%. For shrinkage, cast specimens with iron castings are smaller at 0.35% and resin-coated specimens of 0.40%. For porosity defects, iron castings in the specimens were 8.33 and 8.40 in the core of the resin sand castings. The higher the true density, the more dense the material is. The production time is 555 seconds (9 minutes 15 seconds) from the smelting process of specimens with the core of resin sand castings which is for 829 seconds (13 minutes 49 seconds). Whereas for the process of releasing specimens from molds, products with resin sand castings are faster at 14 seconds, while for specimens with iron castings core is 28 seconds. The cost required to make specimens with iron cast core is Rp. 4,718,500, the cost is cheaper than the manufacture of specimens with core resin sand castings that require capital of Rp. 4,999,000.

ANALISIS PENGARUH JARAK KAMPUH HASIL PENGELASAN BAJA SS400 TERHADAP SIFAT MEKANIK MATERIAL MENGGUNAKAN METODE GMAW

Welding techniques have been used extensively in the construction field because welding techniques are a simpler method in the process of connecting steel than using bolts or rivets. Factors that influence the quality of welding results include distance of the seam. The seam distance can affect the increase in heat input value because the wider the seam distance the more filler metal will be used. The purpose of this study was to determine how the effect of variations in the distance of the seam to the mechanical properties of SS400 steel welding material using the GMAW method. SS400 steel welding welding position 2G with variations in the root gap distance of 0 mm, 2 mm and 4 mm using the GMAW method with a type of protective gas 82% Ar + 18% CO2 and ESAB ER70S-6 type welding wire. Single v butt joint type with a seam angle of 60o and 12 mm thick material. In this study several tests were conducted including distortion testing, non-destructive test, tensile, chemical composition, hardness and microstructure observation. The highest distortion test results obtained at a root gap of 4 mm seam, non-destructive test results showed no welding defects in the upper surface of the weld, the optimal tensile testing results were obtained on a sample root gap of 2 mm with a tensile strength value of 413 MPa and fractures that occurred in the base area metal. The highest hardness test results were obtained at a sample root gap of 0 mm ap with a value of 235 HV and the lowest hardness obtained at a root gap of 4 mm with a value of 209 HV.

PENGARUH PROSES HARDENING BAJA AISI 1045 TERHADAP SIFAT KEAUSAN

AISI 1045 steel is a steel classified as medium carbon alloy steel which is widely used as the main material in machinery so it must have good mechanical properties such as hardness, wear resistance. The purpose of this study was to determine the effect of heat treatment on the wear rate of AISI 1045 steel. The research method used was AISI 1045 steel which was given a hardening heat treatment with a temperature variation of 800ºC, 850ºC, 900ºC with a holding time of 60 minutes, followed by rapid cooling using water . after that the specimen will be tested for wear by using a standard Pin On Disc. the results of the study show that the wear value at 800ºC has an average wear value of 15.0762 mg / cm², then at a temperature of 850ºC has an average wear value of 11.33933 mg / cm² and at a temperature of 900ºC has an average wear value of 9 9488 mg / cm². In conclusion, there was a very strong influence on the use of hardening temperature variations on the AISI 1045 steel wear and the smallest wear value on the specimen given by the hardening process at 900ºC with an average wear value of 9.9488 mg / cm².

ANALISIS KETINGGIAN TOOL PUNCH RIVET TERHADAP HASIL RIVET ING CONTACT PADA SWITCH LAMPU REM MOTOR TIPE C8EA

The product of CBEA Terminal B / B2 Assy is one of the C8EA type Switch components used for brake light switches on two-wheeled vehicles. In the manufacturing process often experience Contact Crack. Contact Crack problems occur in the rivet ing process. This study aims to reduce / eliminate the contact Crack problem, the method used is to conduct research on variations in the height of the punch in the rivet ing process. The initial height of the punch before the research is 49.10 mm, in this study the height of the punch to be examined is 48.60 mm, 48.70 mm, 48.80 mm, 48.90 mm and 49.00 mm. The results obtained for the most appropriate punch height are the height of 48.60 mm with the contact Crack ratio of 3/20, the size of the Crack & contact size entered into the standard, the flexural strength is still standard and the average hardness produced is 92.52 HV which is included in the maximum standard.

ANALISIS KEKUATAN TARIK LOGAM PADUAN Al-Cu-Mg SEBAGAI DUDUKAN SHOCK ABSORBER SEPEDA MOTOR

Aluminum is a non-ferrous metal that has good thermal conductivity and is widely used in various mechanical machinery systems. Efforts to obtain additional mechanical strength from aluminum can be combined with Cu, Mg, Si, Mn, Ni and so on. This research was made to prepare a Motorcycle Shock Absorber that is useful as a pedestal and handle shock breakers against the swing arm, with aluminum alloy material (Al), copper (Cu), and magnesium (Mg). The purpose of this research is to know the tensile strength and know the value of the strain. The method of this research process is aluminum alloy with a variation of Specimen 1 ratio is 3% copper and 7% magnesium, for Specimen 2 replacement is 5% copper and 5% magnesium, and the variations that support Specimen 3 are 7% copper and 3% magnesium. From the results of this study, the tensile strength and strain values ​​obtained in specimen 1 were 125.5 MPa and 3.56%. For specimen 2 the tensile strength and strain values ​​were 150 Mpa and 3.42%. While the specimens of 100% tensile strength and strain are 137 Mpa and 7.48%. The best results from copper and magnesium alloys are Al alloys of 90%, Cu 5% and Mg 5%, with a tensile strength value of 150 MPa and a strain value of 3.42%.

ANALISIS EKSPERIMENTAL KINERJA TURBIN VORTEX AKIBAT PERUBAHAN TINGGI IMPELLER TIPE SUDU BERPENAMPANG LURUS

The use of fossil fuels is now increasing while these resources will be used up if used continuously and these energy resources require a long process to be reused. Alternative energy sources and renewable energy reserves in Indonesia are quite large, but their development has not been optimal because of the geographical gap between the location of energy supply and demand and high technology investment to develop new renewable energy-based technologies and the application of new renewable energy technologies, especially in the electricity sector and as fuel. Based on research that has been carried out on the mechanics of involute inward vortex inflows, the optimal size of the impeller height has not yet been found. This study uses an experimental research method, namely by making a vortex turbine with a straight-section blade type that has a blade height of 180 mm, 210 mm and 240 mm with a water capacity of 10.1471 L / s. loading variations used 3 kg, 3.5 kg, 4 kg, 4.5 kg, 5 kg, 5.5 kg and 6 kg. Tests will be carried out with the above variables on torque, mechanical power and vortex turbine efficiency. The results obtained that the height of the impeller 210 mm has torque, mechanical power and optimal efficiency than the impeller height of 180 mm and 240 mm. The highest mechanical power produced by turbines with an impeller height of 210 mm at a capacity of 10.1471 L / s with a load of 6 kg has a mechanical power of 24.28 watts. The highest efficiency is owned by turbines with a height of 210 mm occurred at a capacity of 10.1471 L / s with a loading of 6 kg, having an efficiency of 37.93%. This is because by adding the height of the impeller to the turbine, the area of ​​the blade affected by the impact of the water fluid becomes more, even when given the turbine loading conditions are not completely submerged. The more blade area submerged by fluid has a more significant influence on the power and efficiency produced than turbines that are resistant to loading even though the turbine is perfectly submerged.

RANCANG BANGUN DAN UNJUK KERJA TUNGKU TEMPA PORTABEL BERBAHAN BAKAR LPG

Selama ini tungku tempa masih banyak yang menggunakan tungku tradisional dengan arang sebagai bahan bakarnya dan tenaga manusia yang menghasilkan hembusan tenaganya, khususnya di daerah pedesaan. Tungku tempa cara tradisional tersebut dirasakan kurang efisien dan susah untuk dipindah-pindahkan. Maka dari itu diperlukan alat tungku tempa portabel berbahan bakar LPG untuk membantu pengrajin pande besi dalam proses pembuatan atau pembentukan produknya sehingga memudahkan dalam melakukan pekerjaan tersebut. Rancang bangun ini menggunakan dua buah burner dengan ukuran kepala burner 1,5 inchi sebagai sumber pijar apinya dan menggunakan keramic fiber, semen tahan panas sebagai pengawet dan penghasil bara api. Dari rancang bangun ini dihasilkan tungku tempa yang mampu melakukan pemanasan material sampai dengan temperatur 850°C.

PENGARUH VARIASI TEMPERATUR HARDENING TERHADAP MECHANICAL PROPERTIES PADA BAJA S45C UNTUK KOMPONEN GRIPER

Baja S45C merupakan jenis baja “Medium Carbon Steel” (0.3-0.5% C). Dalam bidang percetakan, beberapa komponen terbuat dari baja S45C misalnya griper, griper merupakan suatu komponen utama yang digunakan untuk menjepit dan memindahkan kertas pada saat proses cetak, gesekan yang di timbulkan oleh griper akan berdampak terhadap keausan dan perubahan bentuk dari griper dan juga dapat mempengaruhi kualitas hasil cetak. Penelitian ini menggunakan metode pengujian terhadap pengaruh variasi temperatur hardening terhadap mechanical propesties pada baja S45C dengan 3 macam pengujian meliputi pengujian kekerasan, pengujian tarik dan pengujian struktur mikro. Dengan variasi suhu hardening 820 °C, 840 °C, 860 °C ditahan dalam waktu 50 menit kemudian di quenching dengan media pendingin berupa oli,kemudian di tempering dengan dengan suhu 500°C ditahan selama 40 menit kemudian di dinginkan dengan suhu ruang. Hasil pengujian yang diperoleh dari penelitian ini adalah sebagai berikut : Hasil pengujian kekerasan, kekerasan yang paling tinggi di peroleh pada spesimen 4 dengan kode spesimen 860°C/500°C nilai kekerasan sebesar 233.31 HB. Hasil pengujian tarik, kuat tarik yang paling tinggi ada pada spesimen 6 dengan kode 860°C/500°C (A) kuat tarik sebesar 86 kg/mm² jenis patahan yang terjadi adalah patah ulet. Hasil pengujian struktur mikro, tidak terlihat perbedaan yang signifikan antar spesimen karena selisih suhu hardening antar spesimen tidak begitu jauh, fasa yang terlihat pada pengujian struktur mikro di dominasi oleh fasa pearlite dan ferit. Hasil dari pengujian ini, baja S45C yang terbaik untuk komponen griper adalah baja S45C yang telah melalui proses hardening dengan suhu 860°C ditahan selama 50 menit lalu di quenching dengan media pendingin oli kemudian di tempering dengan suhu 500°C ditahan selama 40 menit kemudian di dinginkan dengan suhu ruang. Hasil pengujian kekerasan yang diperoleh paling tinggi yaitu sebesar 233,31 HB dan hasil uji tarik mendapatkan nilai yang cukup tinggi yaitu kekuatan tarik sebesar 86 kg/mm², batas luluh sebesar 57 kg/mm², regangan sebesar 20,52 %, Jenis patahan yang terjadi adalah patah ulet.

MODIFIKASI DAN PENGEMBANGAN MESIN BUBUT SEBAGAI MESIN PENGUJI INJECTION PUMP MOTOR DIESEL PADA KENDARAAN RINGAN

Mesin bubut dapat dirubah kemampuan fungsinya untuk mesin penguji injection pump motor diesel.Merubah kemampuan fungsinya menjadi mesin penguji injection pump motor diesel tersebut dilakukandengan menambahkan alat berupa dudukan injection pump dan sistem bahan bakar motor diesel. Alattambahan yang dibuat terdiri atas dua bagian utama yaitu dudukan injection pump yang mempunyai fungsisebagai dudukan injection pump sehingga poros injection pump segaris dengan pencekam benda kerja danalat tambahan yang kedua yaitu dudukan sistem bahan bakar, khususnya nozel dan gelas ukur sebagaipenampung dan pengukur hasil penyemprotan nozel. Proses pengujian injection pump dilakukan denganmemberikan variasi putaran pada poros injection pump sehingga dapat terbaca volume penyemprotannozel akibat putaran poros injection pump. Modifikasi mesin bubut ini diharapkan dapat dimanfaatkan olehbengkel servis motor diesel yaitu bengkel kecil yang tidak memiliki mesin penguji injection pump danperguruan tinggi khususnya jurusan teknik mesin dan sekolah menengah kejuruan khususnya teknikkendaraan ringan dan alat berat.

ANALISIS PENGARUH PANJANG PIPA HYDROCARBON CRACKING SYSTEM (HCS) TERHADAP PERFORMA MESIN SEPEDA MOTOR

Pada era sekarang ini cadangan minyak bumi semakin menipis, terutama bahan bakar yang berasal dari fosil yang penggunaannya semakin meningkat tajam dengan adanya perkembangan di dunia otomotif dan industri. Oleh karena itu untuk mengurangi pemakaian bahan bakar dengan cara menggunakan alternatif energi baru atau dengan cara melakukan penghematan bahan bakar dengan menggunakan Hydrocarbon Cracking System (HCS).Penelitian ini bertujuan untuk memperoleh data perbandingan unjuk kerja motor bakar 4 langkah dengan variasi panjang pipa katalis yaitu 300 mm, 450 mm dan 500 mm dengan diameter dalam 2 mm dengan bahan bakar premium. Dari hasil penelitian yang dilakukan pada torsi, penggunaan katalis dengan panjang 550 mm menghasilkan torsi tertinggi dibandingkan dengan tanpa menggunakan katalis (standart) yang hanya mencapai torsi maksimum sebesar 4.60 NM sedangkan pada daya penggunaan katalis dengan panjang 550 mm menghasilkan daya tertinggi dibandingkan dengan tanpa menggunakan katalis (standart) yang hanya mencapai daya maksimum sebesar 5.90 hp. Sedangkan pada penggunaan bahan bakar, dengan penambahan katalis terjadi penghematan bahan bakar. Penghematan tertinggi terjadi pada penggunaan pipa katalis dengan panjang 450 mm baik dengan putaran 4000 rpm, 5000 rpm maupun 6000 rpm di bandingkan dengan tanpa pipa katalis. hanya terjadi pada putaran 7000 rpm sedangkan pada putaran 8000 Rpm dan 9000 Rpm penghematan tertinggi pada penggunaan pipa katalis dengan panjang 550 mm.