PG X Jember adalah salah satu agroindustri yang memproduksi gula kristal putih dari tebu. Upaya berkelanjutan diperlukan oleh perusahaan untuk memastikan pasok gula di pasar terjamin; salah satunya adalh dengan melakukan perawatan fasilitas pabrik. Data selama enam bulan di tahun 2018 menunjukkan bahwa pada stasiun ketel terjadi 181 jam downtime. Penyebanya utamanya di antaranya berupa rantai putus dan kerusakan pada bagasse conveyor. Paper ini adalah hasil riset untuk menemukenali penyebab tingginya waktu jam henti pada stasiun ketel tersebut dan upaya perbaikannya. Untuk pengukuran efektivitas mesin pada bagasse conveyor menggunakan metode OEE. Berdasarkan perhitungan, OEE mencapai nilai hingga 68.27% pada bulan Juni. Sedangkan nilai OEE tertinggi mencapai nilai 98.46% pada bulan September. Faktor reduce speed losses berkontribusi sebanyak 46% terhadap rendahnya nilai OEE. Berdasarkan analisa fishbone ditemukan penyebab utama tingginya nilai reduce speed losses adalah kurangnya pengawasann dalam pengangkutan bagasse ke conveyor dan ukuran scrapper tidak sesuai. Agar perusahaan dapat mengurangi losses ini, disarankan untuk memperketat pengawasan ketika pengangkutan bagasse ke conveyor. Dari tinjauan mekanis disarankan supaya mengubah ukuran scrapper agar komponen ini tidak mengalami bengkok dan memperlambat mesin. Analisis free body diagram pada elemen ini menunjukkan bahwa pengurangan dimensi scrapper menjadi 1.195 mm dari 1.215 mm akan mengurangi displacement 6.67 mm menjadi 4.72 mm dengan tanpa mengurangi fungsi kerja bagian ini.

3D printing technology or additive manufacturing is manufacturing by adding materials to objects until it is shaped as expected. This technique is easy and cheap for printing polymer-based materials in the form of filament. Recently, some metal-containing filament has been introduced in the market, one of which is eSteel composed of 45% wt. steel and 55% wt. PLA. Due to its premature introduction, it is a minimal published paper discussing its mechanical properties and dimensional accuracy. This research aims to analyze the dimensional accuracy of 3D printed products of the fused deposition modeling (FDM) technique using eSteel filament. Taguchi method was used to design the experiments with orthogonal array L4 (23). There were three control parameters with two levels each, namely extruder temperature (220°C, 225°C), layer height (0.3 mm, 0.4 mm), and raster angle (0°/90°, 45°/45°). These parameters were selected based on initial trials. The specimens are in the form of an ASTM D790 flexural test with five replications in each combination. HE3D K200 3D printing machine was used for printing the filament. Analysis of variance indicated that raster angle has the most influence on dimensional accuracy by 32.09%, followed by extruder temperature with a contribution of 31.72% and layer height by 25.53%. The combination of control parameters to produce optimal dimensional accuracy was obtained when combining parameters: extruder temperature of 220°C, layer height of 0.3 mm, and raster angle of 0°/90°.

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Al-SiC is a composite composed of AA6061 as a matrix and SiC as a reinforcement particle. The variation of mass added will affect the mechanical properties of the composite because Al-SiC is hardenable, which means that its mechanical properties can be improved by adding the reinforcement component. However, an excessive portion of SiC leads to a decrease in mechanical properties. The purpose of this study was to find the optimal composition of the addition of SiC into the aluminium matrix to gain maximum tensile strength and hardness. The mass fraction variation that would be used in this composite was the addition of 6%, 8%, and 10% SiC with the addition of 1% Mg as a wetting agent. The mixing process used the stir casting method. The process of adding SiC and Mg was carried out by melting the aluminium while stirring it for a certain time before it went to the furnace. The ASTM E8/E8M standard was used for observing the tensile strength of the specimens. Machining was carried out before testing. The specimens were also tested for hardness using the Rockwell hardness method. The result shows that the addition of SiC at the amount of 6%, 8%, and 10% SiC increased the ultimate tensile strength by154.10 MPa, 175.01 MPa, and 198.14 MPa, respectively. Similarly, the hardness also increased up to 30.1 HRF, 48.1 HRF, and 66 HRF, respectively. Microstructure observation also confirmed that a 10% SiC fraction results in less defect and good wettability. The addition of 10% SiC and 1% Mg resulted in maximum tensile strength and hardness and the best microstructure.

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