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"The increasing prices of commercial lubricants and global attention towards a green environment have become the key issues to re-think about alternatives to commercially available lubricants. With these prospects in mind, vegetable oils can be utilized as an option to commercially available lubricants, due to their biodegradable and nontoxic nature. Moreover, they possess certain advantages like lower volatility and high flash/ fire points, higher viscosity index, excellent lubricity and cost savings. These properties of bio-lubricants are more often considered as important in the preparation of various bio-fuels. So far bio-lubricants have been employed in the preparation and testing of bio-fuels for various automotive applications. The primary aim of this study is to infer a novel application of bio-lubricants in the subject area of machining. During machining, machinability and performance are most frequently determined by the friction and wear characteristics of the tool and workpiece materials. In this work, first friction and wear characteristics of bio-lubricants (blended vegetable oils in various proportions) formulated from Palm and Mahua oils have been investigated using a Pin-on-Disk wear testing machine. A bio-lubricant (composed of blended vegetable oils) is synthesized by using two base oils and blending them in different possible proportions. The tribological properties have been studied over an AISI 1040 Steel disc specimen with aluminium pins under various bio-lubricant environments using the Taguchi Design of Experiment (DOE). During the study, it was observed that the abrasive and adhesive wear were the main wear mechanisms that occurred in the tests. The results have shown that total wear of the test specimens under all machining conditions for 90% Mahua and 10% Palm blended oil combination is found to be at a minimum."

"Due to increased environmental sensitivity, renewable-based lubricants, and food grade lubricants are being considered potential alternatives to petroleum-based lubricants. Understanding of bio-lubricant in relation to abrasive wear is essential for using ball bearings in industrial implementation. This study focused on wear mechanism on ball bearings lubricated by bio-lubricants. Palm oil and coconut oils were used in this study. Coconut oils were made by two processes, namely dry and wet processing, resulting in three types of oil (virgin coconut oil [VCO], refined coconut oil [RCO], and hydrogenated coconut oil [HCO]). Full-scale bearing life tests were conducted with 300 N load with 2,840 rpm for 6 hours. Method of lubrication was circulating oil by using pump injection to the self-aligning ball bearings. The results show that the main wear mechanism, which impacted on the surfaces of inner race, outer race, and ball for different bio-lubricants, were abrasive and adhesive wear. It found that the abrasion rate was the least severe for VCO. The discrepancies of worn surfaces are thought to be as a result of the physical and chemical properties of bio-lubricants."

"Kalsium karbonat merupakan aditif padat yang dapat meningkatkan performa anti-wear pada pelumas gemuk. Kinerja aditif dalam mengurangi jumlah keausan dipengaruhi oleh ukuran partikelnya, dimana ukuran partikel yang semakin kecil akan memberikan sifat ketahanan aus yang semakin baik. Namun, partikel yang semakin kecil akan memiliki harga yang semakin mahal. Penelitian ini bertujuan untuk meningkatkan performa gemuk dalam mengurangi jumlah keausan dan memaksimalkan efisiensi biaya dengan mengkombinasikan ukuran partikel aditif kalsium karbonat, yaitu ukuran mikro diatas asperities (Mb), ukuran mikro dibawah asperities (Mk) dan ukuran nano (N). Tiga ukuran tersebut dikombinasikan dengan komposisi berbeda. Pembuatan gemuk dilakukan melalui reaksi saponifikasi minyak sawit sebagai bahan dasar dengan asam 12-hidroksistearat, kalsium hidroksida, dan asam asetat sebagai pengental dan pengompleks. Gemuk bio kalsium kompleks dengan tingkat kekerasan gemuk multiguna (NLGI 2) yang dihasilkan selanjutnya dicampur dengan bubuk aditif kalsium karbonat sebanyak 1% dari basis gemuk, Partikel dikarakterisasi ukurannya menggunakan SEM. Gemuk yang dihasilkan dilakukan pengujian untuk mengetahui jumlah keausan menggunakan uji four ball dan untuk mengetahui pengaruh terhadap karakteristik gemuk yaitu konsistensi, kemuluran, dan dropping point. Hasil penelitian menunjukkan bahwa pada kombinasi mikropartikel dibawah ukuran asperities dan nanopartikel dengan rasio 50% : 50% menghasilkan performa terbaik dalam mengurangi keausan dan mengurangi biaya bahan baku pembuatan gemuk. Penambahan aditif tidak terlalu memengaruhi tingkat penetrasi, kemuluran dan dropping point.

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Calcium carbonate is a solid additive that is well-known for improving the anti-wear performance of bio greases. The performance of additives in reducing the amount of wear can be affected by its particle size, where the smaller particle size will provide better anti-wear performance. However, smaller particles are more expensive. Therefore, research is needed on the particle size combination of calcium carbonate particles on tribological performance to reduce the amount of wear and achieve cost efficient grease. The grease is made through the saponification reaction of palm oil as base oil with 12-hydroxystearic acid, calcium hydroxide, and acetic acid as thickeners and complexing agents. The resulting NLGI 2 calcium complex bio-grease (multi-purpose grease) was then mixed with 1% w/w calcium carbonate powder. The additive particle size was varied into three sizes: micro size above asperities (Mb), micro size below asperities (Mk), and nano size (N). The sizes were varied by its compositions. Particles were characterized using SEM, meanwhile bio-grease using penetration, drop point, and four ball tests. The results showed that the combination of microparticles below asperities (Mk) and nanoparticles (N) with a ratio of 50% : 50% produced the best performance in reducing wear and reducing the cost of raw material for making grease. The addition of additives does not significantly affect the level of penetration, fibril texture and dropping point."

"Aditif pelumas merupakan komponen utama dari pelumas. Aditif memiliki sifat anti-aus dan tahan pada tekanan tinggi. Pembuatan aditif dilakukan dengan proses sulfurisasi minyak biji kapuk randu dengan gas H2S. Proses sulfurisasi dimodifikasi dengan tambahan metode sirkulasi H2S yang berfungsi untuk meningkatkan efisiensi penggunaan H2S. Radiasi sinar UV dengan panjang gelombang 254 nm juga digunakan untuk mempercepat proses sulfurisasi. Proses sulfurisasi dinyatakan berhasil karena ada ikatan C-S pada hasil spektrum FTIR di puncak 581,25 cm-1. Hal ini diperkuat dengan hasıl kandungan sulfur tertinggi yang didapatkan pada sampel minyak biji kapuk randu tersulfurisasi 20 jam sebesar 32.682 ppm dengan viskositas 72,17 cSt dan densities 0,92 g/cm2. Pengujian performa aditif dilakukan dengan uji four-ball untuk melihat performa ketahanan anti-aus pada aditif. Pengujian performa dilakukan dengan mencampurkan minyak mineral sebagai minyak dasar dan aditif. Hasil uji keausan terbaik terdapat pada formulasi minyak mineral dan 10% aditif tersulfurisasi selama 20 jam yang meningkatkan performa keausan hingga 98% dan memiliki rasio sulfur sebesar 3.268 ppm. Rasio sulfur ini sudah sebanding dengan rasio aditif ZDDP yang umum digunakan sebesar 3.393 ppm. Selanjutnya dilakukan pengujian korosifitas pada formulasi minyak mineral dan aditif tersulfurisasi selama 20 jam dan dihasilkan bahwa formulasi tersebut sangat rendah terhadap korosi dan aman digunakan pada mesin kendaraan

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Lubricant additives are the main components of lubricants. These additives possess anti-wear properties and can withstand high pressure. The production of additives is carried out through the sulfurization process of kapok seed oil using H2S gas. The sulfurization process is modified with an additional H2S circulation method to enhance the efficiency of H2S usage. UV radiation with a wavelength of 254 nm is also used to accelerate the sulfurization process. The sulfurization process is deemed successful due to the presence of C-S bonds in the FTIR spectrum at the peak of 581.25 cm-1. This is further supported by the highest sulphur content found in the kapok seed oil sample sulfurized for 20 hours, which was 32,682 ppm with a viscosity of 72.17 cSt and a density of 0.92 g/cm2. Performance testing of the additive was also conducted using a four-ball test to evaluate the anti-wear performance of the additive. The performance test was carried out by mixing mineral oil as the base oil and the additive. The best wear test results were obtained from the formulation of mineral oil and 10% additive sulfurized for 20 hours, which improved wear performance by up to 98% and had a sulphur ratio of 3,268 ppm. This sulphur ratio is comparable to the commonly used ZDDP additive ratio of 3,393 ppm. Additionally, a corrosiveness test was conducted on the formulation of mineral oil and the additive sulfurized for 20 hours, and it was found that this formulation is very low in corrosion and safe for use in vehicle engines."

"Penelitian ini dilakukan untuk mengukur performa rantai pasok pada perusahaan manufaktur pelumas di Indonesia dengan tujuan untuk merancang strategi yang dapat meningkatkan performa kinerja rantai pasok mereka. Kerangka Supply Chain Operations Reference (SCOR) digunakan sebagai metode pengukuran kinerja, metode Analytical Hierarchy Process (AHP) untuk melakukan pembobotan pada setiap indikator, serta sistem pengelompokkan Traffic Light System untuk mengkategorikan kinerja berdasarkan warna. Pengukuran performa kinerja rantai pasok perlu dilakukan untuk mengetahui kondisi rantai pasok dari suatu perusahaan sebagai landasan dilakukannya perbaikan. Perbaikan yang dilakukan dalam penelitian ini dilakukan pada permasalahan di divisi produksi yang berkaitan dengan daya saing perusahaan. Tingkat kepentingan pada indikator kerja diukur berdasarkan pembobotan dengan basis kuisioner oleh beberapa tenaga ahli dalam perusahaan tersebut. Terdapat 43 indikator kinerja (KPI) yang diukur dan terbagi dalam perpektif model SCOR pada tiap levelnya. Hasil pengukuran mengindikasikan performa kinerja rantai pasok perusahaan pada tahun 2019 masuk dalam kategori “baik” dengan nilai rata-rata 72,53%. Setelah itu KPI dipetakan ke dalam kuadran Importance Performance Analysis (IPA), untuk mendapatkan KPI yang sekiranya memiliki performa yang kurang baik dan tingkat kepentingan yang cukup besar untuk diperbaiki. Dari hasil IPA, didapatkan 7 KPI pada rantai pasok perusahaan yang kinerjanya perlu ditingkatkan. Berdasarkan literatur dan diskusi dengan tenaga ahli, didapatkan 9 usulan strategi perbaikan yang dapat dilakukan oleh perusahaan untuk meningkatkan performa kinerja rantai pasok di divisi produksi.

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This research was conducted to measure overall supply chain performance on lubricant company production division with the aim of designing strategies to improve supply chain performance. Supply Chain Operations Reference (SCOR) framework is used as performance measurement method, Analytical Hierarchical Process (AHP) method to weight each indicator, and Traffic Light System to categorize the supply chain performance value based on color. Supply chain performance measurement needed to be done to determine the condition of supply chain of the company as the basis for improvement. Improvements made in this study were carried out for the problems occurred in production division that are related to the company’s competitiveness. The level of importance of the performance indicator is measured by questionnaire to the experts in the company. There are 43 key performance indicator (KPI) measured and breakdowned into SCOR model persepectives at each level. The measurement results indicate that the company’s production division supply chain performance in 2019 is categorized as “good” with the average value of 72,53%. After that, the KPI is mapped into the Importance Performance Analysis (IPA) quadrant to obtain KPIs that has poor performance and level of importance that is high enough to be improved. From the Importance Performance Analysis (IPA) results, there are 7 KPI from the production division that need to be improved. Based on literature and experts discussion, 9 proposed improvement strategies are obtained to improve the supply chain performance in production division."

"Manajemen risiko adalah aktivitas mengidentifikasi, menilai, menganalisis, dan mengendalikan risiko dalam seluruh kegiatan perusahaan dengan tujuan memperoleh efektivitas dan efisiensi yang lebih tinggi. Metode yang digunakan dalam manajemen risiko salah satunya adalah House of Risk (HOR). Metode tersebut merupakan modifikasi antara Failure Mode and Effect Analysis (FMEA) dengan kerangka House of Quality (HOQ) dengan fokus utamanya merumuskan tindakan mitigasi terhadap sumber risiko prioritas yang merupakan penyebab kejadian risiko agregat. Pada penelitian ini, manajemen risiko dilakukan pada aktivitas aliran rantai pasok operasional produksi PT. XYZ. Analisis risiko pada HOR 1 diawali dengan identifikasi risiko melalui diskusi dengan expert dan studi literatur, kemudian dilakukan penilaian terhadap nilai severity dari risk events dan nilai occurrence dari risk agents. Hasil HOR tahap 1 menunjukkan terdapat 23 kejadian risiko dan 21 agen risiko. Berdasarkan perhitungan Pareto, terdapat 12 agen risiko yang mencakup 80% dari total Aggregate Risk Potential (ARP) dan dipilih sebagai prioritas untuk dilakukan mitigasi. Setelah itu, dari hasil HOR tahap 2, ditetapkan 11 tindakan pencegahan yang kemudian digabungkan menjadi 2 strategi mitigasi besar, yaitu menggunakan sistem Epicor Kinetic ERP dan inspeksi rutin.

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Risk management is the activity of identifying, assessing, analysing and controlling risks in all company activities with the aim of achieving higher effectiveness and efficiency. One of the methods used in risk management is House of Risk (HOR). This method is a modification of Failure Mode and Effect Analysis (FMEA) with the House of Quality (HOQ) framework with the main focus on formulating mitigation actions against priority risk sources which are the causes of aggregate risk events. In this research, risk management is carried out in production operational supply chain flow activities at PT. XYZ. Risk analysis in HOR 1 begins with risk identification through discussions with experts and literature studies, then an assessment of the severity value of risk events and the occurrence value of risk agents is carried out. The results of HOR stage 1 showed that there were 23 risk events and 21 risk agents. Based on Pareto calculations, there are 12 risk agents which cover 80% of the total Aggregate Risk Potential (ARP) and were selected as priorities for mitigation. After that, from the results of HOR stage 2, 11 preventive actions were determined which were then combined into 2 major mitigation strategies, namely using the Epicor Kinetic ERP system and routine inspections."