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"Material komposit adalah kombinasi dua atau lebih komponen berbeda yang membentuk material dengan sifat baru. Penyusun material komposit terdiri dari bahan penguat dan matriks. Vacuum infusion ialah proses pembuatan komposit dimana resin dihisap pompa vakum untuk membasahi serat pada cetakan. Terdapat permasalahan terkait geltime resin pada vacuum infusion yang membuat munculnya white spot pada material komposit. Hal ini menyebabkan waktu infusi resin harus diperhatikan. Pada penelitian ini, jumlah dan lapisan serat divariasikan. Didapatkan data waktu infusi resin pada luas serat woven roving 15x20 cm dari dua hingga enam lapis dalam detik : 55, 59, 66, 71, 78; 15x25 cm dari dua hingga enam lapis dalam detik : 119, 142, 168, 198, 235; 15x35 cm dari dua hingga enam lapis dalam detik : 181, 203, 235, 263, 303. Pada pengolahan data, didapatkan hasil panjang dimensi serat maksimum yang dapat dialiri resin, dengan hasil pada jumlah 2 lapisan: Luas 0,4825 m2, Panjang 3,21 m; 3 lapisan: Luas 0,4524 m2, Panjang 3,01 m; 4 lapisan: Luas 0,4506 m2, Panjang 3,00 m; 5 lapisan: Luas 0,4402 m2, Panjang 2,93 m; 6 lapisan: Luas 0,4391 m2, Panjang: 2,92 m. Selain itu, didapatkan jumlah lapisan serat maksimum yang dapat dialiri resin untuk luas 15x20 cm, 15x25 cm, dan 15x35 cm masing-masing 147, 145, dan 123 lapis. Untuk mencegah permasalahan geltime resin, serat woven roving yang dibuat menjadi komposit tidak boleh melewati luas, panjang, dan jumlah lapisan serat maksimum hasil penelitian ini. Pada penelitian ini diketahui resin lebih cepat mengalir pada serat woven roving dibanding serat chopped strand mat.

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Composite material is two or more different components combination to form material with new properties. Composite material consists of reinforcement and matrix. Vacuum infusion is process to make composite in which resin sucked by vacuum pump to moisten fiber in mold. There is a problem in vacuum infusion related to geltime resin, makes white spots appear on composite. This make resin infusion time should be considered. In this research, area and reinforcement layers are variated. This research obtain resin infusion time data for woven roving 15x20 cm in two until six layers in seconds 55, 59, 66, 71, 78 15x25 cm in two until six layers in seconds 119, 142, 168, 198, 235 15x35 cm in two until six layers in seconds 181, 203, 235, 263, 303. Data processing obtained maximum fiber area and length that can flown by resin, with result at 2 layers, Area 0,4825 m2, Length 3,21 m 3 layers Area 0,4524 m2, Length 3,01 m 4 layers Area 0,4506 m2, Length 3,00 m 5 layers Area 0,4402 m2, Length 2,93 m 6 layers Area 0,4391 m2, Length 2,92 m. Maximum fiber total layers that can flown by resin obtain for 15x20 cm, 15x25 cm, and 15x35 cm such as 147, 143, and 125 layer. To overcome resin geltime problem, woven roving fiber that will made must not surpass area, length and total layers maximum in this research. In this research we known that resin is more quickly flow in woven roving fiber than chopped strand mat."

"Material komposit merupakan gabungan dari dua material atau lebih menjadi satu sehingga memiliki sifat-sifat baru yang diinginkan. Sifat-sifat material komposit tersebut sangat dipengaruhi oleh proses manufakturnya. Vacuum infusion merupakan proses manufaktur material komposit modern yang dapat menggantikan metode konvensional. Pada penelitian ini, diperoleh desain peralatan vacuum infusion untuk proses manufaktur material komposit, dengan cetakan berupa kaca yang berukuran 1x1m, wadah resin berupa tabung PVC dengan volume 1L, resin trap berupa tabung kaca dengan volume 1L, dan pompa vakum dengan daya ½ HP serta vacuum speed 7 CFM. Untuk menguji peralatan ini, dilakukan studi pengaruh variasi jumlah lapisan bahan penguat terhadap waktu infusi resin. Luas dan jumlah lapisan bahan penguat divariasikan. Diperoleh waktu infusi resin untuk luas bahan penguat 15x20cm dari dua hingga enam lapis (dalam detik): 88, 115, 145, 174, dan 196; 15x25cm dari dua hingga enam lapis (dalam detik): 119, 142, 168, 198, dan 235; 15x35cm dari dua hingga enam lapis (dalam detik): 181, 203, 235, 263, dan 303. Selain itu diperoleh jumlah lapisan bahan penguat maksimum untuk luas bahan penguat 15x20cm, 15x25cm, dan 15x35cm yang dapat diakomodir masing-masing sebanyak 31 lapis, 29 lapis, dan 25 lapis.

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Composite material is a combination of two or more materials into one material that has the new desired properties. However, the manufacturing process influences the properties of the composite material made. Vacuum infusion is a modern composite material manufacturing process, which can replace conventional manufacturing process. In this study, the design of vacuum infusion equipment for composite materials manufacturing process are manufactured, and consists of: 1x1m glass as the mold, 1L PVC tube for the resin container, 1L glass tube for the resin trap, and ½ HP vacuum pump with 7 CFM vacuum speed. In order to tests this equipment, a study of the influence of reinforcement layers on the resin infusion time is done. The area and reinforcement layers are variated. The resin infusion time for 15x20cm reinforcement from two until six layers (in seconds): 88, 115, 145, 174, and 196; 15x25cm from two until six layers (in seconds): 119, 142, 168, 198, and 235; 15x35cm from two until six layers (in seconds): 181, 203, 235, 263, and 303. Also, the result for the number of maximum reinforcement layers for each 15x20cm, 15x25cm, and 15x35cm area are respectively 31 layers, 29 layers, and 25 layers."

"Komposit sandwich merupakan salah satu material yang banyak digunakan sebagai material penyusun rancang bangun struktur ringan karena memiliki perbandingan strength to weight yang tinggi. Penelitian ini bertujuan untuk membandingkan sifat mekanik komposit sandwich dengan kulit epoksi berpenguat woven roving glass fiber dan inti honeycomb polypropylene dengan metode fabrikasi cold press-adhesive dan Vacuum Assisted Resin Infusion (VARI). Uji tekan, uji tarik, serta uji lentur dilakukan untuk mengetahui kekuatan mekanik, pengamatan morfologi komposit sandwich sebelum dan sesudah pengujian dilakukan untuk mengetahui kerusakan material komposit sandwich tersebut. Hasil penelitian ini menunjukkan komposit sandwich metode VARI memiliki sifat mekanik yang lebih baik dibandingkan komposit sandwich metode cold press-adhesive, yaitu memiliki kuat tekan, kuat tarik, dan kuat lentur secara berurutan sebesar (2,21 ± 0,02) MPa, (0,36 ± 0,04) MPa, dan (26,87 ± 0,30) MPa.

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Sandwich composite is one of the materials that has been widely used as a material for lightweight structures because it has a high strength-to-weight ratio. Sandwich composites with woven roving glass fiber reinforced epoxy skin and honeycomb polypropylene core and their mechanical properties was studied. This research aimed to compare mechanical properties of sandwich composites woven roving glass fiber reinforced epoxy skin and honeycomb polypropylene core with cold press-adhesive and Vacuum Assisted Resin Infusion (VARI) fabrication methods. Compression, tensile, and flexural tests were carried out to determine the mechanical strengths, while morphological observations of the sandwich composites before and after the tests were observed to determine the failures. The results showed that the sandwich composites fabricated by VARI method had better mechanical properties than ones by the cold press-adhesive method, with compressive, tensile, and flexural strength were (2.21 ± 0.02) MPa; (0.36 ± 0.04) MPa; and (26.87 ± 0.30) MPa, respectively."

"A research was being done for analyzing strength and stiffness characteristic of two types of laminated fiber glass/aramid/epoxy composite material. Each type consists of eight and ten layers in same configuration with two different kinds of angle orientations. The base materials used in this research were glass epoxy and aramyd/epoxy fiber composites in which the epoxy is used as matrix. Some mechanical tests and optical observation was carried out for analyzing its macro and micro mechanical characteristics for both types. From the result of mechanical test, it was found that the compressive strength, stiffness and impact characteristic of the second type was better than the first type, but its tensile strength was slightly lower then the first type. In impact test for both type, there was found an increasing in impact strength by decreasing the temperature from 27 °C to -10 °C, which at temperature was -10 °C the both of material was becoming brittle. Optically, it was found that the second type more rigid than first type by observing the shape and direction of its fracture."

"Komposit serat kaca yang diperkuat dengan bahan polimer Glasss Fibre Reinforced Polymer GFRP memiliki kekurangan yaitu kurang tahan terhadap api. Penggunaan clay dapat meningkatkan sifat tahan api terhadap GFRP. Akan tetapi, diperlukan pencampuran yang baik agar clay dapat terdispersi dengan baik. Penelitian ini bertujuan untuk mengetahui pengaruh clay dan kondisi pencampuran terhadap sifat anti bakar, kuat impak, dan modulus lengkung komposit GFRP/clay. Polimer Unsaturated polyester UP , serat kaca, dan 3-Aminopropyltriethoxysilane masing-masing digunakan sebagai matriks, penguat, dan compatibilizer untuk membuat komposit. Unsaturated polyester-clay-silane dicampur menggunakan magnetic stirrer dengan variasi kecepatan dan waktu pencampuran. Komposit unsaturated polyester-serat kaca-clay-silane difabrikasi menggunakan metode vacuum bagging. Variasi clay yang digunakan adalah 1 wt. , 2wt. , dan 3 wt.. Variasi kecepatan rotasi dan waktu pencampuran masing-masing 100,150, 200 rpm dan 60, 90, dan 120 menit. Komposit UP ndash; serat kaca digunakan sebagai bahan pembanding.Hasil penelitian menunjukkan bahwa komposit dengan kandungan clay 1wt tidak terbakar dengan nilai laju bakar sebesar 0 mm/min. Tidak terdapat perubahan variabel yang signifikan pada kuat impak dengan mekanisme berbeda seperti shear dan difusi yang bekerja bersamaan saat mendispersikan clay. Nilai modulus lengkung optimum dimiliki oleh komposit dengan komposisi clay 1 wt _200 rpm_60 menit sebesar 10 0.4 GPa , yang mengalami kenaikan 20 dibandingkan dengan UP ndash; serat kaca.

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Glass fibre reinforced polymer GFRP composites have a weakness in fire resistant property. The addition of clay can improve the fire resistant property of GFRP. However, a good mixing is needed to disperse the clay. This research aims to observe the effect of clay and mixing conditions on fire resistance, impact strength, and flexural modulus of GFRP clay composites. Unsaturated polyester UP , glass fiber and 3 Aminopropyltriethoxysilane respectively were used as a matrix, a reinforcement and a compatibilizer respectively to build the composites. Unsaturated polyester clay silane were mixed using a magnetic stirrer with a variation of rotation speed and mixing duration. The composites were fabricated using a vacuum bagging method. The composition of clay was varied from 1, 2, and 3 wt. The rotation speed and mixing time were varied at 100, 150, 200 rpm and 60, 90, and 120 minutes, respectively. UP glass fiber was used as a comparison material.

The results showed that composites with 1 wt clay content was not burned with the buring rate value of 0 mm min. There were no significant effects of variables on impact strength in between the boundaries that attributed to different mechanisms such as shear and diffusion that worked together to disperse the clay. The optimum flexural modulus was found in the 1 wt clay 200 rpm 60 minute composites with a value of 10 0.4 GPa in which 20 higher compared to the UP glass fibre composites."

"Komposit sandwich merupakan komposit struktur yang diproduksi menjadi panel atau balok ringan yang memiliki sifat kekakuan dan kekuatan yang tinggi. Penelitian ini bertujuan untuk membandingkan sifat mekanik dan morfologi komposit sandwich kulit polyester berpenguat woven roving E glass dan inti honeycomb polypropylene yang difabrikasikan dengan teknik VARI dan adhesif cold-press. Pengujian mekanik yang dilakukan pada penelitian ini adalah uji lentur, uji tarik, dan uji tekan. Pengamatan morfologi pada sebelum dan sesudah pengujian dilakukan dengan menggunakan kamera. Hasil penelitian ini menunjukkan bahwa fabrikasi adhesif cold-press memiliki nilai kekuatan lentur, tarik, dan tekan yang lebih unggul dibandingkan dengan metode VARI yaitu masing-masing sebesar (24,93 ± 0,21) MPa, (0,52 ± 0,02) MPa, dan (1,95 ± 0,05) MPa. Setelah uji lentur, tarik, dan tekan, sampel mengalami kerusakan pada bagian inti.

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Sandwich composites are structural composites that are manufactured into lightweight panels or beams with high stiffness and strength properties. This study aimed to compare the mechanical properties and morphological of polyester skin sandwich reinforced with woven roving E-glass reinforced polyester as skins and a polypropylene honeycomb core fabricated by the VARI and cold-press adhesive techniques. The mechanical tests which were flexural, tensile, and compressive tests were conducted. Morphological observations before and after testing were carried out using a camera. The results of this study indicated that the cold-press adhesive fabrication had superior flexural, tensile, and compressive strength values compared to the ones of VARI method, namely (24,93 ± 0,21) MPa, (0,52 ± 0,02) MPa, and (1,95 ± 0,05) MPa respectively. After bending, tensile, and compressive tests, all samples were failed in the core."

"ABSTRAKSaat ini Indonesia masih mengalami defisit BBM sehingga diperlukan pembangunan kilang minyak yang baru. Pada suatu kilang, terdapat unit operasi sekunder berupa VDU vacuum distillation unit untuk mengolah produk residu atmosferik dari CDU crude distillation unit . Dalam rangka menjaga kestabilan operasi diperlukan sistem pengendalian yang tepat dan optimum. Oleh karena itu, dalam penelitian ini akan dipilih antara pengendali konvensional prorportional-integral, PI dan pengendali lanjut model predictive control, MPC untuk mengendalikan laju alir umpan, suhu umpan, tekanan top-stage, level kondenser, suhu bottom-stage, dan laju alir LVGO light vacuum gas oil , MVGO medium vacuum gas oil , dan HVGO heavy vacuum gas oil . Pengujian kinerja keduanya dilakukan dengan melakukan perubahan set-point dan gangguan sebesar 10 , 25 , dan 50 yang diukur menggunakan nilai ISE integral square error -nya. Hasilnya, untuk pengendalian laju alir umpan, suhu umpan, tekanan top-stage, suhu bottom-stage, dan laju alir LVGO, MVGO, dan HVGO digunakan MPC karena terjadi perbaikan kinerja sebesar 34 , 75 , 97 , 98 , 22 , 68 dan 80 saat pengujian perubahan set-point dibanding dengan pengendali PI, sedangkan untuk pengendalian level kondenser digunakan pengendali PI karena kinerjanya jauh lebih baik dibandingkan dengan MPC. Untuk pengujian gangguan yang sangat besar 50 dari laju alir umpan , persentase kesalahannya pada suhu umpan, tekanan top-stage, level kondenser, suhu bottom-stage, laju alir LVGO, MVGO, dan HVGO masing-masing sebesar 6 , 5,5 , 6 , 5,5 , 0,3 , 0,7 , dan 1,6 .

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ABSTRACTAt this time, Indonesia is still suffering fuel deficit. So that, new oil refinery is needed. In oil refinery, there is secondary process unit, VDU vacuum distillation unit , for processing atmospheric residue from CDU crude distillation unit . In order to maintain the stability of the operation, a proper and optimum control system is required. Therefore, in this study will be selected between conventional controller prorportional integral, PI and advanced controller model predictive control, MPC to control feed flow rate, feed temperature, top stage pressure, condenser level, bottom stage temperature, and the flow rate of LVGO light vacuum gas oil , MVGO medium vacuum gas oil , and HVGO heavy vacuum gas oil . The performance test of MPC and PI which is done by conducting set point and disturbance changes 10 , 25 , and 50 , measured by using ISE integral square error values. As a result, for feed flow control, feed temperature, top stage pressure, bottom stage temperature and flow rate LVGO, MVGO, and HVGO MPC is used due to performance improvements, respectively 34 , 75 , 97 , 98 , 22 , 68 and 80 , in set point changes test compared to PI controllers. While for the level control of condenser, PI control is used because its performance is much better than the MPC. For very large disturbance tests 50 of the feed flow rate , the percentage of error of feed temperature, top stage pressure, condenser level, bottom stage temperature, flow rate LVGO, MVGO and HVGO were 6 5.5 , 6 , 5.5 , 0.3 , 0.7 , and 1.6 respectively."

"Salah satu jenis material yang dewasa ini cukup populer dan berkembang adalah material komposit polimer berpenguat serat gelas (Glass Fiber Reinforced Polymer - GFRP), hal ini dikarenakan nilai ekonomis serta sifat mekanik yang baik yang mampu dihasilkan oleh material komposit tersebut. Ada banyak faktor yang dapat mempengaruhi sifat/ karakteristik material komposit GFRP, diantaranya adalah arah orientasi serat gelas serta perlakuan panas. Penelitian ini membahas mengenai pengaruh orientasi serat gelas woven dan durasi perlakuan panas terhadap sifat/ karakteristik material komposit GFRP. Komposit GFRP yang diorientasikan arah seratnya dimanufaktur dengan menggunakan metode hand lay-up. Spesimen komposit GFRP selanjutnya dikenakan perlakuan panas dan dilakukan pengujian berupa pengujian tarik, tekuk, dan impak, serta dilakukan pengamatan tampilan perpatahan terhadap spesimen uji tarik yang memiliki nilai pengujian tertinggi dan terendah. Dari hasil penelitian yang dilakukan, diperoleh kesimpulan bahwa orientasi serat gelas woven berpengaruh signifikan terhadap sifat tarik dan impak material dan berpengaruh kurang signifikan terhadap sifat tekuk komposit GFRP. Orientasi serat [00 or 900]s pada material komposit GFRP menghasilkan nilai karakteristik tertinggi bila dibandingkan dengan orientasi serat [00 or 900] / [450] dan 450]s. Sedangkan durasi perlakuan panas, tidak memberikan pengaruh terhadap sifat tarik, tekuk, dan impak dari material komposit GFRP.

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One type of materials that is currently quite popular and evolve is a glass fiber reinforced polymer composite material (GFRP). This is due to the economic value and good mechanical properties that can be produced by the composite material. There are many factors that can affect the nature/ characteristics of GFRP composite materials, including the orientation of glass fiber and heat treatment.

This study discusses the influence of woven glass fiber orientation and the duration of heat treatment on the properties/ characteristics of GFRP composite materials. The fiber-oriented GFRP composites were manufactured using the hand lay-up method. GFRP composite specimens subsequently subjected to heat treatment and carried out tests in the form of tensile, bending, impact, and also observation of fracture appearance of tensile test specimens which had the highest and lowest test values.

From the results of the research conducted, it was concluded that the orientation of woven glass fibers had a significant effect on the tensile and impact properties of the material and had a less significant effect on the bending properties of the GFRP composite. The fiber orientation of [00 or 900]s in the GFRP composite material produces the highest characteristic values when compared to the fiber orientation [00 or 900] / [450] and [450]s. While the duration of heat treatment does not affect the tensile, bending and impact properties of the GFRP composite material."