Parameter optimization of 7-wires strand process


  • ศุภัทร ศิลาลอย สำนักวิชาวิศวกรรมศาสตร์และนวัตกรรม มหาวิทยาลัยเทคโนโลยีราชมงคลตะวันออก
  • Parinya Srisattayakul 2Department of Industrial Engineering, Faculty of Engineering, Rajamangala University of Technology Krungthep
  • Chirawat Na-Badalung 1Department of Industrial Engineering and Logistics, School of Engineering and Innovation, Rajamangala University of Technology Tawan-ok



7-wires strand, mechanical properties, central composite design (CCD)


The objective of this research is to study the optimal conditions of mechanical properties on 7-wires strand, to comply customer’s need of mechanical properties conditions respectively; the yield load > 234.6 kN, the breaking load > 261 kN and the elongation > 5%. At the present, the mechanical property of 7-wires strand does not conform to the customer’s specification, which was caused by parameters of 7-wires strand process inconsistency, e.g. tension and temperature. The proposed improvement was applying the Design of Experiment (DOE) using Central Composite Design (CCD) technique where statistical results of optimization indicated the tension of 12980 kg and temperature of 376 °C. When the appropriate values of these parameters were used in the process, it was found that the mechanical properties were increased e.g. the yield load was at 250.6595 kN, the breaking load improved to 277.4124 kN, and the elongation was developed to 5.1985 %.


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How to Cite

ศิลาลอย ศ., Srisattayakul, P. ., & Na-Badalung, C. . (2023). Parameter optimization of 7-wires strand process. RMUTL Engineering Journal, 8(1), 11–20.



Research Article