Study on the Intelligent Control Method of Filling Velocity Oriented to Adjustable Pressure Vacuum Casting

doi:10.3901/JME.2015.21.165

Abstract

Abstract: The warpage quality defect of vacuum casting (VC) parts is usually caused by unstable filling velocity, so the adjustable pressure VC process is proposed. The filling mechanism is analyzed, it is demonstrated that the differential pressure is the key process parameter which affect filling velocity. The filling velocity control strategy is developed by analyzing the relationship between valve opening and filling velocity. The strategy implementation process is introduced. The voxel model of VC part is constructed based on STL model and the features of cavity such as volume and cross sectional area are obtained. In order to gain the theoretical control curve of valve opening, the numerical simulation of mold filling process is carried out adopting control volume method. The fuzzy logic controller (FLC) of valve opening is constructed which using two-dimensional table to realize fuzzy inference, thus the respond speed is quick and the overshoot is low. Finally, combined with concrete examples, the experiments are carried out using test experiment platform. The experiments results fully reflected the advantages of adjustable pressure VC process and proved the feasibility of control strategy and improved the quality of VC parts. In a word, the method is new and useful process for VC technology.

Key words: filling mechanism, fuzzy logic control, numerical simulation, vacuum casting

ZHANG Haiguang, SONG Chenxia, HU Qingxi. Study on the Intelligent Control Method of Filling Velocity Oriented to Adjustable Pressure Vacuum Casting[J]. Journal of Mechanical Engineering, 2015, 51(21): 165-173.

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