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Reliability Study of Oil and Gas Pipelines Using the Normal Distribution Method Suhendi Syafei, Nendi; Hidayat, Darmawan; Rohadi, Nanang; Joebaedi, Khafsah; Supriyana, Eddy
EKSAKTA: Berkala Ilmiah Bidang MIPA Vol. 22 No. 1 (2021): Eksakta : Berkala Ilmiah Bidang MIPA (E-ISSN : 2549-7464)
Publisher : Faculty of Mathematics and Natural Sciences (FMIPA), Universitas Negeri Padang, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (827.147 KB) | DOI: 10.24036/eksakta/vol22-iss1/246

Abstract

Gas and oil pipelines have decreased function and damaged due to corrosion. This research aims to analyze and predict the life of gas and oil pipelines within a certain time span. The method used is a reliability study using a normal distribution. The analysis results show it is predicted that the pipe reliability probability in 2030 will decrease and the probability of failure will increase. The probability of reliability is 0.843572786617270 and the probability of failure is 0.156427213382730 in 2030. With the long distance pipeline, maximum depth as shown in the attachment the average thick remain is 0.2200 inches, the average corrotion rate is 0.0317 mm/year, with prediction thick remain from 2000 to 2030 in inches.
A Comparison of Polyol Ester and Mineral Oil under Thermal Aging Rajab, Abdul; Kamil, Insannul; Kamarol Mohd Jamil, Mohamad; Kurniawan, Septian Ari; Rohadi, Nanang; Emiliano, Emiliano
Andalasian International Journal of Applied Science, Engineering and Technology Vol. 5 No. 2 (2025): July 2025
Publisher : LPPM Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/aijaset.v5i02.231

Abstract

Insulating oil was historically dominated by mineral oil due to its cost-effectiveness and good properties. However, the limitations of mineral oil, particularly its availability and environmental concerns, present significant long-term operational risks. Polyol esters, synthesized through specific chemical processes, demonstrate biodegradability and operational safety. This research evaluates the electrical, physical, and chemical properties of both oil types, focusing on parameters such as breakdown voltage, water content, acidity, viscosity, and density. Results indicate that polyol ester oils exhibit a more stable breakdown voltage and better moisture management due to higher water absorption capacity, and greater density stability and viscosity even after prolonged thermal aging. Despite a more pronounced increase in acidity, polyol ester oils positioning as a promising and sustainable alternative for long-term use in oil-filled electrical equipment such as transformers. This aligns with industry objectives for enhanced environmental sustainability and operational reliability.
Implementasi PID Auto Tuning Berbasis PLC Omron untuk Pengendalian Kestabilan Kecepatan Motor Induksi Tiga Fasa terhadap Variasi Beban: Sebuah Studi Eksperimenta Rohadi, Nanang; Liu Kin Men; Akik Hidayat
Jurnal Nasional Teknik Elektro dan Teknologi Informasi Vol 14 No 4: November 2025
Publisher : This journal is published by the Department of Electrical and Information Engineering, Faculty of Engineering, Universitas Gadjah Mada.

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jnteti.v14i4.22693

Abstract

Speed regulation of three-phase induction motors under varying load conditions presents a major challenge in industrial automation due to their nonlinear dynamic behavior. This paper proposes an adaptive speed control system using a PID Auto-Tuning (PIDAT) algorithm implemented on the Omron CP1H-XA40DT-D Programmable Logic Controller (PLC). The initial PID parameters are derived using the Ziegler–Nichols method, and the system continuously monitors steady-state error during operation. When the error exceeds a predefined 5% threshold, the auto-tuning sequence is triggered. This sequence includes a Relay Feedback Test (RFT), system identification using a First-Order Plus Dead Time (FOPDT) model, and real-time PID parameter recalculation. The system hardware integrates an Omron 3G3MX2 inverter, rotary encoder, and NB7W-TW01B Human–Machine Interface (HMI) to form a closed-loop control structure. Experimental validation was performed under both spontaneous and constant load conditions. The PIDAT method consistently demonstrated superior performance compared to classical Ziegler–Nichols tuning, achieving steady-state errors in no-load tests below 1.70 % and under 0.8% in loaded conditions. Furthermore, the system achieved settling times below 9 seconds and recovered from load disturbances in less than 4 seconds. These results validate the proposed PIDAT system as an accurate, fast, and adaptive control solution, reducing the need for manual tuning and enhancing robustness in dynamic industrial environments.