
第33卷第11期
文章编号:10069348(2016)11025906
计算机仿真
2016年11月
液压静力压桩机油泵溢流阀建模控制优化仿真
胡均平,杨根,李科军,刘成沛(中南大学机电工程学院,朝南长沙410083)
摘要:针对液压静力压桩机油泵溢流阔建压时间过长的问题,为探究阀中各参数对其建压过程的影响规律,运用功率键合图法建立了阀的数学模型,运用Matlab仿真软件分析了阔主要参数对其建压过程的影响规律,并通过现场实验验证了所建模型的正确性。定义了阻尼孔结构参数C,以衡量细长阻尼孔的阻尼大小。研究结果表明;主阀阻尼孔结构参数及主阅弹簧刚度对建压时间、卸荷压力以及高压澄流压力均有影响,且前者不得小于2.5mm",后者不得大于20x10"N/m;主阀弹簧预压缩量仅对建压时间有明显影响,先导阅各参数仅对高压澄流压力有影响;主阀芯与先导阀芯质量对建压过程无明显影响。
参数优化后溢流阅的建压时间可缩短84%。研究为油泵溢流阀性能优化提供了参考。关键调:澄流阀;建压过程;功率键合图;阻尼孔结构参数;液压静力压桩机
中图分类号:TP391.9
文献标识码:B
Modeling Controlling and Optimization Simulation of theHydraulicStaticPilingDriver'sPumpReliefValve
HU Jun-ping,YANG Gen,LI Ke-jun,LIU Cheng-pei
(School of Mechanical and Electrical Engineering, Central South University, Changsha Hunan 410083, China) ABSTRACT: In order to reduce thepressure building time of the oil pump relief valve of the hydraulic static piling driver, the influence of key panaumeters of the valve on the pressure building process is studied through modeling and simulation method. A mathematical model of the valve is established through the bond graph method, the effects of the valve parameters are analyzedthrough Matlab, andan experiment is conducted to verify the simulation model., To measure the damping of the long and thin orifice more simply, a parameter named Damping Orifice Structure Parame-ter (Cf) is defined. The results indicate that, Cf of the main valve and the stiffness of the main valve spring affect the pressure building time, the unloading pressure and the high over flow pressure, The former shouldnot be smaller than 2. 5mm3 and the later one shouldnot be bigger than 20x103 N/m. The precompression of the main valve spring only has obvious effects on the pressure building time, and parameters of the pilot valve only influence the high over flow pressure. Neither the main valve spool mass nor the pilot valve spool mass has obvious effects on the pressure building process, After parameters optimization, the pressure building time can be reduced by 84%.
KEYWORDS: Relief valve; Pressure building process; Bond graph; Damping orifice structure parameter; Hydraulic static piling driver
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引言
静压法施工是一种通过液压静力压桩机以其自身及其
配重的重力将预制桩压人土层的沉桩工艺,其液压系统常采用外控先导式溢流阀远程建压。采用这种建压方式一方面能避免频紫繁启停油泵,延长油泵使用寿命,另一方面能减少能量消耗,降低机器的使用成本,因而在工程机中得到了广泛应用。但在实际应用中,该种建压方式的建压时间较长,某公司600吨液压静力压桩机液压系统的建压时间需要
基金项目:国家自然科学基金(51175518)收稿日期:2016-0123
:修回日期:2016-0129
万方数据
2~3秒。由于机器施工过程中需要频紫建压,故溢流阀的建压时间对机器的施工效率有严重影响。
过去对溢流阀的研究主要集中在当通过澄流阀的流量发生阶跃变化时,如何提高溢流阀的动态特性-4);或当液压系统负载压力突然增大时,如何提高溢流阅的开启灵敏性以实现快速溢流[5-6];或是当人口流量发生变化时,如何提高溢流阀的压力流量特性以保证溢流压力受流量的影响尽可能小{)。而对溢流阀实际应用中从低压卸荷状态切换到高压溢流状态的建压过程的研究较少。罗春雷等提出影响外控先导澄流阀建压时闻的关键原因是与其先导口相连的多路阀阀芯间原的泄露,而对澄流阅本身结构参数对建压时间的影响未做深人研究*);周明对液压静力压桩机上双溢流阅从
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