Article Per Year (5 Year)
p-Index From 2021 - 2026
0.947
P-Index
This Author published in this journals
All Journal Sinergi International Journal of Innovation in Mechanical Engineering and Advanced Materials Jurnal Polimesin
Haftirman Haftirman
Department Of Mechanical Engineering, Faculty Of Engineering, Universitas Mercu Buana
Automotive Engineering Civil Engineering, Building, Construction & Architecture Control & Systems Engineering Electrical & Electronics Engineering Energy Engineering Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mechanical Engineering

Published : 4 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 4 Documents
Search

 1 
TRIBOLOGICAL PROPERTIES OF AL2O3-ZrO2 COMPOSITE COATING BY LUBRICATION Riyadh A. Al-Samarai; Haftirman Haftirman
SINERGI Vol 25, No 3 (2021)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2021.3.014

Abstract

Tribological investigations had been carried out on the plasma coating (Al2O3+ ZrO2) below dry and moist abrasion stipulations according to ASTM G134. Commercial motor oil 20W40 was used as a lubricant. At a rotational speed of 200 rpm, all experiments were carried out with ordinary loads of 10, 15 and 20 Nm. Electron microscopy for scanning and AFM was used to study of the layer sprayed with paint. The outcomes of the SEM and AFM evaluation confirmed that abrasive wear is normally decided by abrasive wear in dry abrasive conditions. The lubrication and moisture check confirmed a major reduce in wear from 10 to 15 N below regular loading, and a corrosion fee larger than 15 N was once discovered below regular loading. No impact of lubrication on wear used to discovered at high loading. No impact of lubrication on wear used to be discovered at high loads. It was also cited that the plasma coating manner to improve wear resistance. The experimental statistics acquired in this study are tremendous engineering functions such as reducing equipment and internal combustion engines. 
Design optimization and material selection of automotive bushing arms using FEA under acidic exposure Ana Nur Oktaviani; Dafit Feriyanto; Haftirman Haftirman; Supaat Zakaria; Dedik Romahadi; Hadi Pranoto; SS Abdulmalik
Jurnal Polimesin Vol 24, No 3 (2026): June
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v24i3.8444

Abstract

Bushing arms are critical automotive components that function as vibration dampers and load absorbers. The problem is that the bushing arm often fails due to several factors, including the use of inappropriate materials, poor road quality, lack of routine maintenance, and external factors such as extreme temperatures, exposure to corrosion, and excessive pressure. This study aims to optimize bushing arm design and material selection to improve durability and vibration-damping performance under acidic exposure conditions. Two rubber materials, Natural Rubber (NR) and Ethylene-Propylene Diene Monomer (EPDM), were evaluated for MPV-type vehicle bushing arms. Three design variations were developed and analyzed using hyperelastic Finite Element Analysis (FEA) to assess stress distribution, strain, deformation, and safety factor. The rubber specimens were fabricated by hot pressing at 180°C and 7 MPa, followed by immersion in 15% phosphoric acid at 65°C to evaluate chemical degradation. Mechanical characterization included tensile testing (ASTM D412), Shore hardness testing, and microstructural observation. The results showed that acid immersion reduced tensile strength by 20.44% for NR and 23.80% for EPDM, while elongation decreased by 38.3% and 17.43%, respectively. Hardness decreased by 19.2% for NR and 4.81% for EPDM. FEA results indicated that design C achieved the lowest deformation, reducing it by 51%, while design B reduced shear stress and von Mises stress by up to 70%. Based on the combined mechanical and simulation results, design B with NR material was selected as the preferred configuration.
Viability of R-290 Refrigerant as Residential AC Retrofit: Effect of Charge Mass Variations Irham Aulia; Haftirman Haftirman; Ega Taqwali Berman
International Journal of Innovation in Mechanical Engineering and Advanced Materials Vol. 7 No. 2 (2025)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/ijimeam.v7i2.30904

Abstract

The growing concerns over ozone depletion and global warming caused by refrigerants have led to the search for environmentally friendly alternatives. This study evaluates the impact of varying R-290 refrigerant charge masses on the performance of a wall-mounted residential air conditioner using the drop-in substitute method. A ¾ HP residential AC unit originally charged with 550 grams of R-22 refrigerant was retrofitted with R-290 and tested at charge masses of 140 grams, 165 grams, and 190 grams—approximately 25%, 30%, and 35% of the original R-22 charge, in accordance with the commonly applied “one-third rule.” The results showed that retrofitting with R-290 increased the Refrigeration Effect (RE) by up to 75%, Compression Work (Wc) by 68%, and Coefficient of Performance (COP) by up to 18%. The system with a 25% refrigerant charge was unable to reach the set temperature due to a 23% reduction in cooling capacity, while the 30% charge showed a 10% reduction. The 35% refrigerant mass retrofit proved the most suitable, achieving adequate cooling capacity, an 18% increase in COP, and a 14% reduction in power consumption. Additionally, the retrofit resulted in an indirect CO₂ emission reduction of 1.15 metric tons annually, highlighting the environmental and energy-saving advantages of using R-290. These findings provide empirical validation of the one-third rule for refrigerant mass variation in R-290 retrofits and offer valuable insights into optimizing performance and efficiency in residential AC units, with significant energy and environmental benefits.
ENERGY AND COSTS SAVING AIR CONDITIONING SYSTEM OF SHOPPING MALL BUILDINGS: A CASE STUDY IN JAKARTA Agus Marjianto; Haftirman Haftirman
International Journal of Innovation in Mechanical Engineering and Advanced Materials Vol. 3 No. 3 (2021)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/ijimeam.v3i3.11857

Abstract

The air conditioning system for the Mall A building in Jakarta uses a central air conditioning system with a constant flow chiller with TES (Thermal Energy Storage). This system will be verified by measuring data regarding cooling load of the Mall A. The peak cooling load measurement results is 12,299 kW with a total cooling load of 45,733,180 kWh for 1 year. The result of the measurement data will be compared to cooling load calculation by Trace 700 software. Based on Trace 700 software, the peak cooling load is 12,594 kW with a total cooling load of 44,617,405 kWh. Furthermore, using the actual measurement data of the air conditioning system in Mall A, it will be compared with a central air conditioning system with a magnetic bearing chiller which will be equipped with VSD (Variable Speed Drive) to find out how well its energy performance and costs are for a mall building similar to Mall A, as a potential for energy and cost savings. The results of energy calculations and cost analysis, the central air conditioning system with the magnetic bearing chiller is 99 kWh/(m2.year) and the life cycle costs for 20 years, 30 years, and 50 years are 339,828,248,242 IDR, 415,994,136,400 IDR, 521,915,598,761 IDR. While the results of energy calculations and cost analysis, the TES combination constant flow chiller central air conditioning system is 141 kWh/(m2.year) and the life cycle costs for 20 years, 30 years, and 50 years are 435,150,140,059 IDR, 541,700,386,487 IDR, 690,535,151,478 IDR. Based on the foregoing, the central air conditioning system with variable flow magnetic bearing chiller is a better system than the central air conditioning system with TES combination constant flow chiller for shopping mall buildings similar to Mall A.
Co-Authors Agus Marjianto Ana Nur Oktaviani Dafit Feriyanto Dedik Romahadi Ega Taqwali Berman Hadi Pranoto Irham Aulia Riyadh A. Al-Samarai SS Abdulmalik Supaat Zakaria