SPROCKET JOURNAL OF MECHANICAL ENGINEERING

Keausan Yang Terjadi Pada Kampas Ganda Akibat Adanya Gesekan Dengan Clutch Cover (Matahari Kopling) Pada Forklift Di PT. ABC

Herry Darmadi — 2025-08-28

Forklift is one of the means of transportation used in PT ABC. PT ABC is the first company to produce fish oil and flour using whole fish as raw material. Wear on engine components is a problem that is often faced in industry, especially in heavy equipment such as forklifts. One component that experiences significant wear is the double clutch, which functions as a connection between the engine and transmission in the clutch system. One of the main causes of wear on the double clutch is friction that occurs with the clutch cover (clutch sun). This study aims to determine the amount of wear volume that occurs on the double clutch and to determine the amount of wear rate that occurs on the double clutch. The method used in this study is data analysis. From the results of the study, it can be concluded that the Wear Volume that occurs on the double clutch is 7.1053 x 10^-4 mm³ and the Wear Rate that occurs on the double clutch is 2.13624343 x 10^-18 g / sec.mm².

Perencanaan Pemeliharaan Mesin Pompa Centrifugal dengan Menggunakan Metode Reliability Centered Maintenance (RCM): Studi Kasus PT Nabati Asahan

Septri Asri Enjelina Sinaga — 2025-08-28

PT Multimas Nabati Asahan is one of the vegetable oil producers that experiences a high frequency of sudden breakdowns in centrifugal pump machines, averaging 12 hours per month, which negatively impacts production target achievement, operational efficiency, and increased production costs. The research methodology includes the identification of critical components, failure analysis through Failure Mode and Effect Analysis (FMEA) and Logic Tree Analysis (LTA) to determine the priority of maintenance actions. The research results show that the mechanical seal is the component with the highest RPN value of 504, followed by the rubber coupling and bearing. From the task selection results, maintenance action recommendations berupa time directed maintenance, condition based maintenance, and failure finding were obtained. The implementation of RCM is capable of reducing the frequency of sudden failures, optimizing maintenance costs, and improving the reliability and productivity of centrifugal pump machines. This research is expected to serve as a strategic reference in the machinery maintenance management system in the palm oil processing industry.

Keywords: Reliability Centered Maintenance, FMEA, Logic Tree Analysis, Downtime, Centrifugal Pump Machine.

Pengaruh Penggunaan Crumb Rubber sebagai Substitusi Agregat Halus terhadap Kuat Tekan Beton Tidak Bertulang

Defri Suganda — 2025-08-28

This study aims to analyze the effect of using crumb rubber (used tire powder) as a partial substitution of fine aggregate in unreinforced concrete. especially compressive strength and concrete weight. Crumb rubber variations used were 0%, 5%, 15%, and 25% of the volume of fine aggregate. Tests were conducted on 15 cm × 30 cm cylindrical specimens treated for 28 days. The main parameters tested included compressive strength and water absorption. The results showed that the addition of crumb rubber decreased the compressive strength of concrete significantly, the highest compressive strength was obtained in normal concrete (25.8 MPa), while the mixture of 25% crumb rubber produced the lowest compressive strength (3.9 MPa). However, it provides advantages in terms of lighter specific gravity and better water absorption. However, the addition of crumb rubber reduced the weight of the concrete by 19.4%. The use of crumb rubber at 5% is considered the most optimal alternative with a decrease in compressive strength that is still within the tolerance limit for non-structural concrete. This research supports the utilization of waste tires as an effort to support sustainable development.

Keywords: crumb rubber, non-reinforced concrete, waste tires, compressive strength, lightweight concrete

Besarnya Penyusutan Yang Terjadi Pada Peleburan Logam Non-Fero Dengan Menggunakan Bahan Baku 2.5 Ton Logam Untuk Pembuatan Komponen Boiler Pada Tanur Kupola Di PT. X

Herry Darmadi — 2025-08-28

The casting industry is a kind of mining industry, where all industry manufacturing would never exist without the casting of the casting industry, much more difficult for the economy of a country without its own industrial role. A brushwork furnace that is one of the most popular types of metal smelting kitchens. The large shrink that occurs at smelting metals for making boiler components using 2.5 tons of raw materials is 15.08 percent or weighing 2,123 kg. the foundry in PT X using cocash-fuel (coal with high carbon levels). The process of smelting metals included sand prints that served the desired components, supplying raw materials and fuel to suit needs, smelting the kiln in my furnace with the help of blowers, pouring the molten metal into the ground, and cooling the molten metal.

Penerapan Reliability Centered Maintenace untuk Pemeliharaan Mesin Crane di PT Pelindo

Levi Silaban — 2025-08-28

This study aims to analyze the implementation of Reliability Centered Maintenance (RCM) in the maintenance of crane machines at PT Pelindo. Cranes play a vital role in port loading and unloading activities, making operational reliability essential for smooth logistics operations. The RCM approach is used to identify critical components based on potential failures, their impact on operations, and the effectiveness of maintenance actions. Data were collected through observation, interviews, documentation, and questionnaires, and analyzed using Failure Mode Effect Analysis (FMEA), Mean Time Between Failure (MTBF), Mean Time To Repair (MTTR), and Availability. The results indicate that components such as the contactor, carbon collector, and motor hoist/gearbox have the highest Risk Priority Number (RPN), requiring prioritized maintenance. The MTBF value of 317.687 hours reflects a relatively high level of machine reliability, while the MTTR of 3.25 hours demonstrates repair efficiency. The implementation of RCM has proven effective in improving reliability, reducing downtime, and minimizing maintenance costs. The study recommends enhancing preventive and predictive maintenance, as well as training technicians to efficiently detect and manage failures.

Keywords: Reliability Centered Maintenance, crane, maintenance, FMEA, MTBF, MTTR

Penerapan Metode Total Productive Maintenance Dan Overall Equipment Effectiveness Pada Mesin Sterilizer Di PT. Tri Cahaya Sawit

Roy Aldo Sihombing — 2025-08-28

Machine effectiveness is a critical factor in ensuring smooth operations within the palm oil processing industry. One of the most vital machines in this process is the sterilizer, which functions to deactivate enzymes, soften fruit, and facilitate the detachment of fruit bunches. This study aims to evaluate the effectiveness level of the sterilizer machine at PT. Tri Cahaya Sawit using the Overall Equipment Effectiveness (OEE) method and to propose an improvement strategy based on Total Productive Maintenance (TPM). This research adopts a quantitative case study approach with descriptive analysis. Data were collected through direct observation, interviews, and company documentation from March to June 2024. The three OEE parameters analyzed include availability, performance, and quality rate. The results showed an average OEE value of 82.5%, with an availability rate of 92.67%, performance rate of 91.87%, and quality rate of 97.43%. These figures remain below the world-class OEE benchmark of 85%. The primary factors contributing to low effectiveness were high downtime and suboptimal maintenance scheduling. Fishbone diagram analysis revealed that the dominant causes included reactive maintenance practices, lack of operator training, and inadequate maintenance documentation. Therefore, the implementation of the eight TPM pillars—particularly autonomous maintenance and planned maintenance—is proposed to enhance the reliability and efficiency of the sterilizer machine. This study concludes that OEE serves as an effective evaluation tool to identify operational losses, and a structured TPM implementation can significantly improve machine performance and overall company productivity.

Keywords: Total Productive Maintenance, Overall Equipment Effectiveness, Sterilizer Machine, Downtime, Productivity.

Optimasi Proses Pengecoran Aluminium pada Produksi Komponen Produk Cor untuk Peningkatan Kualitas dan Efisiensi

Nur Rokhim — 2025-08-28

Penelitian ini mengkaji pengaruh variasi suhu penuangan terhadap kualitas pengecoran paduan aluminium ingot AC4A dengan metode cetakan pasir CO₂. Suhu penuangan yang diuji adalah 650°C dan 664°C, dengan parameter yield dan mikrostruktur produk cor. Hasil penelitian menunjukkan bahwa peningkatan suhu penuangan berdampak positif terhadap kualitas hasil cor. Kekerasan Vickers meningkat sebesar 9,26%, dari 54,73 HV pada suhu 650°C menjadi 59,8 HV pada 664°C. Yield juga meningkat dari 10,62% menjadi 10,92%, yang menunjukkan efisiensi material yang lebih baik. Analisis mikrostruktur pada pembesaran 100x menunjukkan bahwa pengecoran pada suhu 664°C menghasilkan struktur dendritik α-Al yang lebih halus, distribusi fasa eutektik Si yang lebih merata, serta porositas yang lebih rendah. Suhu penuangan 664°C direkomendasikan sebagai parameter optimal untuk mencapai kualitas mekanis dan efisiensi produksi yang lebih baik. Temuan ini diharapkan dapat menjadi dasar pengembangan lebih lanjut proses pengecoran aluminium dalam skala laboratorium maupun pendidikan teknik.

Kajian Eksperimental Daya dan Konsumsi Bahan Bakar Mesin Pembakaran Internal dengan Bioetanol dari Sorgum sebagai Sumber Energi Terbarukan

Sugiyarto Sugiyarto — 2025-08-28

The dependence on fossil fuels as a primary energy source has led to serious environmental and economic problems, including the scarcity of non-renewable natural resources and significant environmental impacts. There is a need to find cleaner and more sustainable renewable energy sources to reduce dependence on fossil fuels and mitigate environmental damage. One promising alternative is bioethanol from sorghum (Sorghum Bicolor). The liquid from sorghum stalks is fermented and distilled to produce bioethanol, which is then blended with gasoline (Pertamax) in various concentrations (E10, E20, and E30). A dynotest was used to measure the power output, and a measuring cup was used to test the fuel consumption of a single-cylinder gasoline engine at idle speed. Engine power and fuel consumption were the parameters analyzed. The research showed that the higher the bioethanol content in the fuel, the more fuel-efficient it became, but the higher the power output generated by the engine. The E30 blend produced the best results in terms of engine power and fuel consumption. This is due to the more uniform fuel mixture, which results in better fuel expansion. These findings support sorghum bioethanol as a sustainable alternative fuel and promote a shift towards clean energy in industry and transportation.

Rancang Bangun Alat Latihan Kelincahan Dribel Bola Basket Berbasis Arduino Dan Android

Agus Noviar Putra — 2025-08-28

Penelitian ini bertujuan mengembangkan alat bantu pelatihan kelincahan dribel bola basket berbasis Arduino dan Android yang mampu memberikan instruksi secara acak, mendeteksi respons pemain secara real-time, serta merekam data waktu tempuh pada setiap titik lampu. Alat ini diharapkan menjadi solusi praktis dalam pelatihan berbasis data yang lebih objektif dan efisien. Metode penelitian menggunakan pendekatan waterfall yang meliputi empat tahap utama: analisis, desain, implementasi, dan pengujian. Hasil pengujian menunjukkan bahwa sensor, LED, dan speaker berfungsi 100% dengan baik, sedangkan modul memiliki tingkat keberhasilan 90% yang masih memerlukan peningkatan pada akurasi pembacaan. Perangkat timer dan pendeteksi pada aplikasi Android juga memiliki tingkat akurasi 90%. Uji coba alat melibatkan 5 pemain bola basket dengan 5 titik tempuh dan 3 kali pengujian, menghasilkan total waktu tempuh 29,274 detik dengan rata-rata 5,855 detik per titik. Data menunjukkan performa peserta relatif stabil pada setiap pengujian. Temuan ini membuktikan bahwa alat yang dikembangkan efektif digunakan untuk mendukung latihan kelincahan dribel bola basket berbasis data.

Analisis Kinerja Dan Efisiensi Energi Mesin Water Cooled Chiller Di Gedung Capital Place Tower Jakarta

ASRI ASRI — 2025-08-28

This study aims to calculate the COP (Coefficient of Performance) value of the chiller and determine whether the value is better than the standard value. The analysis includes taking data on temperature, pressure, evaporator and condenser water flow, amperage and voltage in the compressor on the chiller, then calculating the COP to determine the efficiency of the chiller machine performance. The results of the calculation state that the highest COP value of chiller No. 2 is 7.4 and the lowest is 7.0 in the efficient category referring to the chiller standard of 7.22. While the highest COP of chiller no. 3 is 7.4 and the lowest is 5.1 in the inefficient category referring to the chiller standard of 7.22. The results of the calculation of the capacity of chiller No. 2 at 100% compressor load, the resulting cooling capacity is only 77.29-90%, the potential for increasing efficiency that can be optimized in chiller No. 2 is 22.71-39.38%. Chiller No. 3 at 100% compressor load produces only 83.34-66.89% of the cooling capacity, while the potential efficiency increase that can be optimized in chiller No. 3 is 33.11-37%. To increase chiller efficiency, set the chilled water temperature setpoint not too low between 7-80C adjusted to actual needs, load changes and environmental conditions.