Hydraulic systems control based on the characteristics of major-motion mechanism for an open-die forging manipulator

Jiaoyi Hou,Yongjun Gong,Hua Zhou,Zengmeng Zhang,Dayong Ning

doi:10.1177/1687814017690959

Jiaoyi Hou, Yongjun Gong + Show 3 more

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https://doi.org/10.1177/1687814017690959

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Abstract

In the open-die forging process, the forging manipulator must cooperate closely with the forging press. Terrible working conditions of open-die forging have resulted in significant demand on the hydraulic control systems of the forging manipulator. This article analyzes the characteristics of major-motion hydraulic systems with the aim of proposing a novel hybrid serial–parallel heavy-duty forging manipulator. Kinematic and dynamic models of the major-motion mechanism are developed to investigate the control and comply with performance of hydraulic lifting, pitching, and buffering systems. Simulation shows that the three hydraulic systems are coupled in the position and posture control of the clamp. A separate posture control method based on the characteristic of the major-motion mechanism is designed for the hydraulic systems, and the position tracking performance of the hydraulic systems is studied in a stretching process of a plat-tool.

Highlights

The rapid development of nuclear power, hydropower, and ship engineering has resulted in higher demand for heavy forgings worldwide
A forging manipulator is an auxiliary equipment in open-die forging that adjusts the posture of the clamp and controls the feeding of the workpiece
This study aims to investigate the control characteristic of the clamp and workpiece for a new type parallel forging manipulator

Summary

Introduction

The rapid development of nuclear power, hydropower, and ship engineering has resulted in higher demand for heavy forgings worldwide. High quality, and high precision are three main characteristics of open-die forging. A forging manipulator is an auxiliary equipment in open-die forging that adjusts the posture of the clamp and controls the feeding of the workpiece. The ability to operate a forging manipulator is a key factor that affects forging precision and efficiency. Forging is one of the industry’s most arduous tasks,[1] and the working conditions of the forging manipulator can be quite difficult. Hydraulic systems have been widely used in different industries because of their high power density, fine dynamic response, and ability to produce large force and torque. Most forging manipulators, especially heavy-duty ones, are driven by hydraulic actuators.[2]

Objectives

Conclusion