Design and Performance Evaluation of Hydraulic Fixing System for Aircraft Skin Milling Flexible Jigs
Abstract
Manufacturing aircraft skin components requires high precision and structural integrity because of the process complexity. Traditional bolt friction brake fixation methods have resulted in inadequate stiffness, leading to suboptimal machining accuracy and surface finish. To address these issues, this study proposes a hydraulic fixation system to improve the stiffness of flexible jigs in CNC milling of aluminum plates. The hydraulic system's performance was assessed via stiffness tests and repeated precision measurements, demonstrating significant improvements over conventional methods. The horizontal stiffness increased to 11.6 N/μm, marking an 830% improvement over that of bolt friction brakes, and the vertical stiffness reached 190 N/μm. Furthermore, the hydraulic system achieved an axial precision of 1 μm and radial precision of 5 μm under a working pressure of 30 MPa. These results underscore the effectiveness of hydraulic fixation systems for enhancing machining quality and fixture reliability in aerospace manufacturing.
Keywords:
Hydraulic fixture, Flexible jig, Aircraft skin, Stiffness, Repeated precision, Bolt fixtureAcknowledgments
This paper was supported by the Regional Innovation Cluster Development (R&D) Project (Project Number P0025337) funded by the Ministry of Trade, Industry and Energy (MOTIE) of the Republic of Korea.
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Student in the School of Mechanical Engineering, Gyeongsang National University.His research interest is CAM and CNC Machining.
E-mail: junt3460@gnu.ac.kr
Student in the School of Mechanical Engineering, Gyeongsang National University.His research interest is CNC Machining and Machining Precision.
E-mail: mount7429@naver.com
University Student in the School of Mechanical and Aerospace Engineering, Gyeongsang National University.His research interest is CAD and Prototype production.
E-mail: zz4342@naver.com
Student in the School of Mechanical Engineering, Gyeongsang National University.Her research interest is Mechanical Design and CNC Machining.
E-mail: aallen@naver.com
Student in the School of Mechanical Engineering, Gyeongsang National University.Her research interest is CNC Machining and Production Quality.
E-mail: subean0607@gnu.ac.kr
University Student in the School of Mechanical and Aerospace Engineering, Gyeongsang National University.His research interest is Hydraulic System Design and Components Analysis.
E-mail: msdos621@naver.com
Professor in the School of Mechanical and Aerospace Engineering, Gyeongsang National University.His research interest is CAM and CNC Machining.
E-mail: sujinkim@gnu.ac.kr
CEO of JAMS Co., Ltd. He is also Leading the Company's Affiliated Research Institute, Where He is Developing a Universal Vacuum Fixture for Aircraft Skin Machining.
E-mail: jhhuh@jamskorea.com