Research On Constant Force Grinding Control System Of Abrasive Belt Grinder

Along with the rapid development of Petroleum, nuclear power, constructionmachinery industries and other industries, the higher requirements of processingprecision and performance for large-scale pipe fittings and shaft parts such as pumpingshiny rods used in oil field pumping units, oil pipelines, high pressure and hightemperature alloy pipelines used in nuclear power, hydraulic piston rod were putforward. The cylindrical abrasive belt grinding technology is efficient, precise, low-costmodern processing method, which was very suitable for processing large-scale pipefittings and shaft parts. However, the surface shape of large-scale pipe fittings and shaftparts were not regular round, which caused abrasive belt grinding head could not followthe workpiece shape variations timely and lead to large differences of grinding force inworkpiece prominences and recesses in the grinding process, so that the surface qualityof workpiece was very poor and it`s performance can not meet the actual requirements.In order to improve the grinding quality, abrasive belt grinding head must follow theworkpiece`s shape variations timely to ensure that the grinding force is constant.Therefore, it was very meaningful to research the adaptive control technology ofgrinding force in the cylindrical abrasive belt grinder.This paper took cylindrical belt grinder that had four grinding heads as the researchobject, for the problem of grinding uneven existed in grinding process, analyzed relatedresearch situation at home and abroad, carried out the study of constant force abrasivebelt grinding control technology. Main research contents were as follows:①The abrasive belt grinding head mechanism was the most critical part of thefour heads combination abrasive belt grinder. At present, the pneumatic control systemwas used to control abrasive belt grinding head mechanism to ensure that the grindingforce is constant. However, the disadvantages existed in the pneumatic system such asgas compression and small working pressure affected the grinding precision very much.Therefore, the electro-hydraulic proportional control system was designed to control thegrinding head mechanism.②According to the grinding head mechanism of abrasive belt grinder andelectro-hydraulic proportional control system, researched and established themathematical models of all parts of the system, then simplified and deduced the generalmathematical model of the system. ③Analyzed and researched control algorithm of constant force grinding controlsystem in abrasive belt grinder, and designed the Fuzzy Self-adaptive PID based on thecharacteristics of the control system, and the simulation analysis was done.④According to control function requirements of the abrasive belt grinder,selected the control system hardwares, and used LabVIEW, Fuzzy Logic Toolkit,LabSQL and PID Toolkit to design the software of abrasive belt grinder constant forcegrinding control system.⑤The preliminary experiment research was carried out under the existingconditions of the hydraulic laboratory, to verify the feasibility of the hydraulic systemand monitoring software designed in this paper.