Research On Pressure Control Of Evenness Padder

The padder plays an important role in dyeing,the structure and property of it has a significant influence on the pick up and uniformity of the fabric after rolling.In order to improve the dyeing effect of the fabric,the roll contour of the padder also put forward higher requirements.Comparing to the ordinary padder,evenness padder has an oil chamber inside,after inletting the pressure oil can make the roll line pressure and pick up evenly.Therefore,enterprises are paying more and more attention to the research and development of the air pressure and oil pressure matching and control precision of the evenness padder to improve the effect of fabric dyeing.In this paper,first,the squeezing characteristic of the fabric were analyzed.Secondly,the method of numerical analysis was used to analyze the distribution regularity of the line pressure under the pneumatic and hydraulic pressure.Then the MH552-180 evenness padder and the control precision was improved,and visual input and feedback were realized.Finally,through the experiment,the rationality of the simulation results were verified.This paper mainly completed the following works:1.The mechanical model of evenness padder and properties of fluid removal from fabrics by squeezing was established.The design of small padder experiment was designed and based on the experimental results,which fitted the relationship between the fabric line pressure and the pick up.2.Based on the ALE fluid-solid coupling method,the circumferential model of evenness padder was established by LS-DYNA software.The influence of the rotation and the cyclic loading of internal oil pressure on the deformation of the padder surface was analyzed.3.The influence of air pressure and oil pressure on the roll line pressure of evenness padder was analyzed.The test schemes of different air pressure and oil pressure was designed and simulated by LS-DYNA software.According to the simulation results,the reasonable ratio range of air pressure and oil pressure and the effective width was obtained.The compatibility model of air pressure and oil pressure was established.4.Based on the original MH552-180 evenness padder of the air and oil system,in order to improve the oil pressure and pressure control accuracy of the evenness padder,the digital electro-pneumatic regulator,pressure transmitter and S7-200 PLC were switched.The touch screen interface was designed,and the human-computer interaction was realized with S7-200 PLC.5.The experiment of MH552-180 evenness padder was designed,and the pick up uniformity of the simulation results was measured.The relationship between the air pressure and oil pressure of the product specification and simulation results ware compared.