本文選題：冷擺輾成形 + 擺頭運動軌跡　； 參考：《機械科學(xué)研究總院》2015年博士論文

【摘要】：本文以具有圓、直線、螺旋線和多葉玫瑰線四種擺頭運動軌跡的立式冷擺輾機為研究對象,針對直線、螺旋線和多葉玫瑰線運動軌跡無法實現(xiàn)連續(xù)局部成形問題,提出橢圓、不過中心的螺旋線和多葉玫瑰線的擺頭新型運動軌跡。在冷擺輾成形力的理論研究及試驗的基礎(chǔ)上,對擺頭擺角對擺輾成形力影響、擺頭不同運動軌跡成形過程進(jìn)行深入研究。這一課題的研究將解決目前冷擺輾機直線軌跡應(yīng)用少、螺旋線和多葉玫瑰線軌跡沒有實際應(yīng)用的狀況,為改進(jìn)擺頭結(jié)構(gòu)、設(shè)計新型擺輾機和拓展冷擺輾成形工藝提供理論依據(jù)。在分析立式冷擺輾機擺頭結(jié)構(gòu)及運動原理基礎(chǔ)上,建立擺頭運動方程,推導(dǎo)出圓、直線、螺旋線和多葉玫瑰線四種運動軌跡的形成機理及規(guī)律,通過對擺頭四種運動軌跡特點分析,建立擺頭擺角與內(nèi)、外偏心套夾角函數(shù)關(guān)系,提出擺頭新型運動軌跡,并對其運動方程及規(guī)律進(jìn)行理論分析,對擺頭運動機構(gòu)的改進(jìn)可行性進(jìn)行了論證。擺頭新型運動軌跡避開了軌跡中心點,可實現(xiàn)成形過程中的連續(xù)局部成形,降低擺輾成形力,改善擺頭受力狀況。通過冷擺輾成形影響因素及受力分析,針對目前擺輾接觸面積在擺角較小時計算誤差大造成擺輾成形力計算不準(zhǔn)確的問題,重新推導(dǎo)擺輾成形接觸面積的計算公式并進(jìn)行校驗,建構(gòu)擺輾成形力與工藝參數(shù)關(guān)系,完善擺輾成形力理論計算公式,為不同運動軌跡擺輾成形力分析提供了理論基礎(chǔ)。在研制的2000kN立式冷擺輾機上,以法蘭件為試驗對象,擺頭采用圓運動軌跡在不同擺角下進(jìn)行擺輾成形試驗,采集擺輾成形力變化數(shù)據(jù),結(jié)合Deform-3D有限元模擬擺輾成形過程,分析、校驗數(shù)值模擬結(jié)果以及擺輾成形力計算公式,得出擺頭擺角與擺輾成形力關(guān)系圖,為運動軌跡改進(jìn)的參數(shù)選擇提供理論依據(jù)。建立擺頭三維運動軌跡方程,應(yīng)用MATLAB軟件對擺輾成形過程三維曲線進(jìn)行仿真,對不同運動軌跡擺輾成形過程曲線理論分析,結(jié)合圓、螺旋線和多葉玫瑰線運動軌跡擺輾成形試驗,對運動軌跡改進(jìn)前、后成形過程規(guī)律及特點進(jìn)行分析。本文建立了擺頭運動方程、擺頭擺角與偏心套夾角函數(shù)關(guān)系、擺輾成形力理論計算公式,分析了擺頭改進(jìn)前、后運動軌跡的形成機理及規(guī)律,通過理論分析、模擬研究與成形試驗比較、驗證,得出擺角與擺輾成形力關(guān)系以及不同運動軌跡擺輾成形過程曲線及特點,論證了改進(jìn)運動軌跡的優(yōu)勢。
[Abstract]:In this paper, the vertical cold rolling machine with circular, straight, helical and multi-leaf rose lines is taken as the research object. Aiming at the problem that the motion trajectory of straight line, spiral line and multi-leaf rose line can not realize continuous local forming, an ellipse is proposed.But the spiral of the center and the new trajectory of the pendulum of the leafy rose line.On the basis of the theoretical study and experiment of the forming force of cold rotary rolling, the effect of pendulum angle on the forming force and the forming process of different moving trajectories of the pendulum head are studied in depth.The research of this subject will solve the problem that the linear track of cold rotary rolling machine is few and the track of spiral line and multi-leaf rose line has no practical application at present. It provides a theoretical basis for improving the structure of the pendulum head, designing a new type of rotary rolling machine and expanding the forming technology of cold rotary rolling.Based on the analysis of the structure and motion principle of the pendulum head of the vertical cold rotary rolling machine, the motion equation of the pendulum head is established, and the forming mechanism and law of four motion trajectories of circle, straight line, spiral line and multi-leaf rose line are deduced.Based on the analysis of the characteristics of the four kinds of motion trajectories of the pendulum head, the relationship between the swing angle of the pendulum head and the angle function of the inner and outer eccentric sleeve is established, and the new motion trajectory of the pendulum head is put forward, and its motion equation and law are analyzed theoretically.The feasibility of improving the movement mechanism of swinging head is demonstrated.The new trajectory of swinging head can avoid the center point of the trajectory and can realize continuous local forming in the forming process, reduce the forming force and improve the force condition of the swinging head.Based on the analysis of the influence factors and forces on the cold rotary rolling forming, aiming at the problem of inaccurate calculation of the forming force caused by the large error in the calculation of the contact area in the rotary rolling at present, the formula for calculating the contact area of the rotary rolling forming is rededuced and verified.The relationship between forming force and technological parameters is constructed, and the theoretical formula of forming force is perfected, which provides a theoretical basis for the analysis of forming force of rotary forging with different motion trajectories.In the 2000kN vertical cold rotary rolling machine, taking flange parts as the test object, the swinging head adopts circular motion track to carry out the forming test under different swing angles, collects the data of the changing force of the rotary rolling, simulates the forming process of the rotary rolling with Deform-3D finite element method, and analyzes the forming process of the pendulum rolling.By checking the numerical simulation results and calculating formula of the forming force of rotary rolling, the diagram of the relationship between the swing angle of the pendulum head and the forming force of the rotary rolling is obtained, which provides a theoretical basis for the parameter selection of the motion trajectory improvement.The three-dimensional motion trajectory equation of the pendulum head is established, and the three-dimensional curve of the forming process is simulated by using MATLAB software. The theoretical analysis of the curve of different motion trajectory is carried out, and the circle is combined with the curve theory.The forming process and characteristics of spiral and multi-leaf rose lines were analyzed before and after the motion trajectory was improved.In this paper, the equation of swinging head motion, the relation between the swing angle and the angle function of eccentric sleeve, the theoretical calculation formula of forming force in rotary rolling are established, and the formation mechanism and law of the trajectory before and after the improvement of the pendulum head are analyzed.By comparing the simulation research with the forming test, the relationship between the swing angle and the forming force, the curves and characteristics of the forming process of different motion tracks are obtained, and the advantages of improving the motion trajectory are demonstrated.
【學(xué)位授予單位】：機械科學(xué)研究總院
【學(xué)位級別】：博士
【學(xué)位授予年份】：2015
【分類號】：TG306

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 胡亞民;;起動齒輪端面齒形的冷擺輾成形[J];鍛壓機械;1989年03期

2 伍太賓;;國內(nèi)外擺動輾壓技術(shù)的研究和發(fā)展[J];精密成形工程;2009年03期

，

本文編號：1766756