高空作业车液压和电气控制系统设计[含CAD图纸和说明书等资料]
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Shield tunneling machine hydraulic system synchronization control Simulation AnalysisHun Guoliang Abstract: A thrust hydraulic system of shield tunnellingmachine integration of p ressure and flow controlwas designed1Simulationanalysis of synchronizing thrust for thrust hydraulic system was carried out usingAMESim andMATLAB software1The simulation resultsshow that there are good synchronizing effects by app lying synchronization controlwith master2slave mode, and the synchronization precision can be controlled within 1mm, which can p rovide the references for the shield tunnels。Keywords: Shield tunnellingmachine；Thrust hydraulic system；Synchronization control；Simulation。.Shield tunnellingmachine is a mechanical, electrical, hydraulic, measurement and control technology in the multidisciplinary integration, For the underground tunnel excavation of the major projects in technology-intensive equipment. It is excavating speed, high quality and labor intensity, high security, the right of surface subsidence and the environmental impact of small advantages, with the traditional method of drilling and blasting tunnel construction compared to the more obvious advantages, especially in complex geological conditions. a high water table depth of the tunnel and a larger, they can only rely on the shield. Propulsion system is the key to shield one of the main commitments of the entire shield jacking tasks required to complete Shield turning, The road curves, attitude control, and synchronous rectification campaign. Propulsion system to control Shield in overcoming the course of the advance encountered resistance on the premise that Driving under the process of construction, the various strata and soil changes in the earth pressure, to promote the right speed and pressure without advance-level coordination regulation, Shield tunneling makes the process as possible simultaneously to avoid unnecessary digging and less-digging To achieve control, Hydraulic System Requirements advance to the nonlinear variable load conditions and the pressure to achieve real-time control of volume, and require high reliability. Based on this, this paper to promote the hydraulic system synchronization control was related to simulation analysis. 1 Promoting an integrated design of hydraulic systems Shields hydraulic system is more complex, belonging to change load, high power, low flow applications. The system in the main oil pump along variable load-sensitive control; For six cylinder actuator will be divided into six groups, for a control to the completion of this progress, individual advancement or retreat. Double-forward or backward movements. All of a control module are the same, are proportional relief valve proportional valve, electromagnetic valve, auxiliary valve testing and related components and so on. Figure 1 hydraulic system to promote the work of a single diagram. Shield, the two-pass an electromagnetic valve power outages, system pressure oil ratio by two outflow valve, At this time three or four electromagnetic valve 9 Switch to state B position, the hydraulic cylinder piston rod 6 forward movement. Promote the process, the hydraulic cylinder 6 of displacement sensors embedded real-time detection of seven advancing displacement, Feedback converted into electrical signals proportional to the speed control valve proportional solenoid 2, Speed ratio control valve 2 throttle opening, thereby advancing the speed of the real-time control, At this point the system redundant flow from proportional relief valve 3 outflow. To achieve attitude, it is also necessary to promote real-time control pressure At this time the pressure sensor can detect five of the six cylinder pressure advance, Feedback converted into electrical signals proportional to the ratio of three relief valve electromagnet, 3 proportional valve control the throttle opening is to be achieved. The proportion of a relief valve 3 and proportional flow control valve and pressure sensor 2 5 7 and displacement sensor with the pressure flow Minute a control, real-time control propulsion systems driving speed and pressure. Rapid regression, two-pass an electromagnetic valve in the power, short-circuit ratio valve 2, the system using a large flow of oil, At this time three or four electromagnetic valve 9 switched to a working state position, the hydraulic cylinder piston rod six rapid regression, Segment to meet assembly requirements.Various sub-groups, 8 hydraulic lock and Y-type function of three or four electromagnetic valve 9 locking components together into a loop median may very well cease to prevent the leakage of hydraulic oil. Hydraulic cylinder returned, the balance valve four could play a role in stabilizing campaign. 2 promote multi-cylinder hydraulic system simulation Cylinder the synchronous movement is very important, especially in the changing load shield equipment appear to be even more pronounced. Due to the special nature of the work Shield, Shield knife before the excavation site to the frequent load changes in straight forward cases, If we do not take the necessary synchronization measures to promote the process of setting Shield of deviation from the track, unnecessary or less dug-dug, it may even cause Shield poor equipment performance, failure or damage. Propulsion system caused various hydraulic cylinder is not a synchronized for many reasons, mainly in the following aspects : (1) Gain flow, the initial work current, linear zone differences, made the opening when a flow proportional flow control valve flow is not equal, with the result that when the hydraulic cylinder movement is not synchronous. (2) hydraulic cylinder under different load, tunneling process Shield Cutter Face water pressure changes are random. Thus, all of a hydraulic cylinder to bear the load size, Carrying large hydraulic cylinder smaller than carrying hydraulic cylinder running slow. (3) The hydraulic cylinder manufacture precision errors, leading to the Deputy Campaign hydraulic cylinder friction different; In addition, Installed with the deputy campaign gap, deputy campaign makes no equivalent friction. Friction large hydraulic cylinders running relatively slow.Figure 2 promote multi-cylinder hydraulic system simulation model Simulation of two hydraulic cylinder and the same speed as the input. Figure 3 and Figure 4 for the two symmetrical hydraulic cylinder pressure and the speed of simulation map. From the map you can see that since the two hydraulic cylinders suffered load, No.2 hydraulic cylinder pressure on the hydraulic cylinder than No.5 suffered some major atmospheric pressure. In addition, the No.2 hydraulic cylinder and viscous friction coefficient ratio No.5 hydraulic cylinder and viscous friction coefficient also, reflected in the speed has been different, force, viscous friction coefficient of hydraulic cylinder speed to advance more slowly, From Figure 4 advancing speed simulation curves, we can see that this time No.2 tank promoting stability in the rate of 36mm per minute. No.5 tanks and stability after the advance rate of about 39mm per minute. Figures 5 and 6 for the two hydraulic cylinder displacement and displacement curves for the poor simulation curve. As the No.2 hydraulic cylinder No.5 advancing faster than hydraulic cylinder speed of the advance to the small, as time increases, two hydraulic cylinder displacement poor is also growing. Figure 6 shows that in the course of time to reach the 50s, the two hydraulic cylinder displacement of the poor to 215mm. In other words, every advance 1min, about 3mm of error, It may lead to the actual process of shield tunneling deviate from the pre-set trajectory. it is necessary to take immediate control strategy. 3 to promote multi-cylinder hydraulic system simulation analysis of synchronous control now we often used hydraulic synchronous control in two major ways. One is the open-loop-control methods that use streaming manifold valve, synchronous cylinder, synchronous motors and other components synchronous hydraulic circuit, Its characteristics are the principle is simple and low cost, but also low accuracy. The second method is to use electro-hydraulic servo valves, or electro-hydraulic proportional valve components closed-loop control system, the adoption of this closed-loop control method, the same way and master-slave approach commonly used two control strategy using this control strategy is expected to be high-precision synchronization control requirements 7. Simulation using master-slave synchronization control, No.2 hydraulic cylinder as the main hydraulic cylinders, hydraulic cylinder as No.5 from the hydraulic cylinder. No.2 hydraulic cylinder to the output of the ideal output No.5 hydraulic cylinder under control to track the selected ideal output and achieve.Figure 7 for promoting multi-cylinder hydraulic system simulation AMESim synchronous model, Figure 8 Simulink was used to promote the construction of multi-cylinder hydraulic system simulation model synchronization. Simulation parameters obtained with the lack of synchronization control of the same, and two hydraulic cylinder speed input were the same. Given suffered load and hydraulic cylinder and viscous friction coefficient, to promote the process of hydraulic cylinder driving speed and displacement different. At this point, No.2 and No.5 two hydraulic cylinder displacement input to the S AMESim function, Then the output interface control structures Simulink simulation model. Simulation of the two-cylinder displacement of poor and the displacement settings, the differential displacement feedback signal to speed settings, compensation to achieve synchronization cFigure 9 and Figure 10 using synchronous control of the hydraulic cylinder pressure and the speed of simulation curve. From the map you can see that two hydraulic cylinder pressure on the map with three no synchronization control measures adopted to promote the pressure curve, the there is no change. However, Figure 10 shows, this time from the two main hydraulic cylinder speed of the advance of basic coincidence, promoting the stability of both 36mm per minute speed. Figure 11 and Figure 12 for two hydraulic cylinder displacement and displacement curves for the poor simulation curve. As the No.2 hydraulic cylinder speed of the advance and No.5 hydraulic cylinder speed of the advance of the same, So two hydraulic cylinder displacement of very similar. Figure 12 shows two hydraulic cylinder displacement of poor 01025mm only completely satisfy the control requirements.4 Conclusion This paper to promote a multi-cylinder hydraulic system to promote the simulation analysis, Comparing the absence of synchronization and the use of two simultaneous control of the simulation results. Simulation results show that the master-slave synchronization control strategy to achieve better propulsion systems simultaneously coordinated campaign Hydraulic cylinder can be controlled simultaneously accuracy of 1mm between actual Shield simultaneously provide a reference. 盾构推进液压系统同步协调控制仿真分析胡国良摘要: 设计了一种基于压力流量复合控制的盾构推进液压系统。采用AMESIM和MATLAB仿真软件对推进液压系统同步协调控制进行了仿真比较分析。仿真结果表明采用主从式同步控制策略能够达到很好的同步效果, 同步精度达到1mm,为实际盾构同步推进提供了参考依据关键词: 盾构；推进液压系统；同步控制；仿真。盾构是一种集机械、电器、液压、测量和控制等多学科技术于一体、专用于地下隧道工程开挖的技术密集型重大工程装备。它具有开挖速度快、质量高、人员劳动强度小、安全性高、对地表沉降和环境影响小等优点, 与传统的钻爆法隧道施工相比更具有明显的优势, 尤其在地质条件复杂、地下水位高而隧道埋深较大时, 只能依赖盾构。推进系统是盾构的关键系统之一, 主要承担着整个盾构的顶进任务, 要求完成盾构的转弯、曲线行进、姿态控制、纠偏以及同步运动等。推进系统的控制目标是在克服盾构推进过程中遇到的推进阻力的前提下, 根据掘进过程中所处的不同施工地层土质及其土压力的变化, 能够对推进速度及推进压力进行无级协调调节, 使得盾构在掘进过程中尽可能达到同步推进, 避免不必要的超挖和欠挖。为了达到控制要求, 推进液压系统要求能够在非线性变负载工况下实现压力和流量的实时控制, 并要求具有高的可靠性。基于此, 本文对推进液压系统的同步协调控制作了相关仿真分析研究。1推进液压系统集成设计盾构推进液压系统比较复杂, 属于变负载、大功率、小流量的应用场合。本系统在主油路上采用变量泵实现负载敏感控制; 对于6个执行元件液压缸, 将其分为6组, 进行分组控制, 以完成全推进、单个前进或后退、双个前进或后退等动作。各个分组的控制模块都相同, 均由比例溢流阀、比例调速阀、电磁换向阀、辅助阀及相关检测元件等组成。图1为推进液压系统单个分组的工作原理图。盾构推进时,二位二通电磁换向阀1 断电, 系统压力油经比例调速阀2 流出, 此时三位四通电磁换向阀9切换到工作状态B位置, 液压缸6 的活塞杆向前运动。推进过程中, 液压缸6 中的内置式位移传感器7 实时检测推进位移, 转换成电信号反馈到比例调速阀2 的比例电磁铁上, 控制比例调速阀2中节流口的开度, 从而实现推进速度的实时控制, 此时系统中多余的流量可从比例溢流阀3中流出。为了实现姿态调整, 还必须实时控制推进压力, 此时可由压力传感器5 检测液压缸6 的推进压力, 转换成电信号反馈到比例溢流阀3的比例电磁铁上, 控制比例溢流阀3的节流口开度来实现。分组中的比例溢流阀3和比例调速阀2与压力传感器5和位移传感器7一起构成压力流量复合控制, 可实时控制推进系统的推进速度和推进压力。快速回退时, 二位二通电磁换向阀1得电, 短路比例调速阀2, 系统采用大流量供油, 此时三位四通电磁换向阀9切换到工作状态A位置, 液压缸6的活塞杆快速回退, 以满足管片拼装的要求。各个分组中, 液压锁8 与具有Y型中位机能的三位四通电磁换向阀9组成在一起成为锁紧回路, 中位停止时可很好的防止液压油的泄漏。液压缸退回时, 平衡阀4能起到运动平稳的作用。2推进液压系统多缸仿真分析多缸机构的同步运动十分重要, 特别是在变负载的盾构设备中显得更为突出。由于盾构工作的特殊性, 盾构刀盘开挖面前方的负载经常发生变化, 在直线推进的情况下, 如果不采取必要的同步措施, 推进过程中盾构将偏离设定的轨道, 引起不必要的超挖或欠挖, 甚至会造成盾构设备性能低劣、失效或损坏。造成推进系统中各个分组液压缸不同步的原因有很多种, 主要有以下几个方面:(1) 由于流量增益不同、起始工作电流不同、线性工作区有差异, 使得在某一开度时流过比例调速阀的流量不相等, 从而导致液压缸运动时不同步。(2) 液压缸承受负载不同, 掘进过程中盾构刀盘工作面的水土压力都是随机变化的, 因此各个分组中的液压缸承受的负载大小也不同, 承载大的液压缸较承载小的液压缸运行慢。(3) 液压缸的制造精度有误差, 导致液压缸运动副摩擦力也不同; 另外, 安装时运动副的配合间隙不同, 使得运动副摩擦力也不相等。摩擦力大的液压缸运行相对慢。(4) 液压系统安装时油管长度和弯头数目的不同也会造成液压缸沿程阻力不相等; 此外, 长时间运行也会使得液压缸的工作特性发生变化, 这些因素也会导致各个分组中的液压缸推进时不同步 5 - 6 。基于此, 首先对没有采取同步控制措施的左右对称的2#和5#推进液压缸进行仿真分析。模拟实际推进过程中分区液压缸所受负载不同以及液压缸所受内摩擦力的不同。仿真中把2#液压缸的粘性摩擦系数设为1 104N /m / s, 负载中的弹簧刚度设为1 1010 N /m;而5#液压缸的粘性摩擦系数则设为1 103N /m / s, 负载中的弹簧刚度设为5 109N /m。图2为采用AMESim仿真软件搭建的推进液压系统多缸仿真模型图。图2推进液压系统多缸仿真模型仿真时两个液压缸的调速输入设为相同。图3和图4为两个左右对称液压缸的推进压力和推进速度仿真图。从图中可以看出, 由于两个液压缸所受负载不同, 2#液压缸所受压力比5#液压缸所受压力约大2MPa。另外, 2#液压缸的粘性摩擦系数比5#液压缸的粘性摩擦系数也要大, 反映在速度上也有所不同,受力大、粘性摩擦系数大的液压缸推进速度要慢些,从图4推进速度仿真曲线可以看出, 此时2#缸稳定后的推进速度为36mm /min, 而5#缸稳定后的推进速度约为39mm /min。图5和图6为两个液压缸的位移仿真曲线和位移差仿真曲线图。由于2#液压缸的推进速度比5#液压缸的推进速度要小, 随着时间的增大, 两个液压缸的位移差也越来越大。从图6可以看出, 在推进时间到达50 s时, 两个液压缸的推进位移差达到215mm。也就是说, 每推进1min, 就有约3mm的误差, 这样很容易导致实际掘进过程中盾构偏离预先设定的轨线,因此有必要采取同步控制策略。3推进液压系统多缸同步控制仿真分析目前常采用的液压同步控制方法主要有两种。一种是开环式的控制方法, 即用分流集流阀、同步缸、同步马达等组成同步液压回路, 其特点是原理简单,成本低, 但精度也较低。第二种方法是用电液伺服阀或电液比例阀组成闭环控制系统, 采用这种闭环控制方法时, “同等方式”和“主从方式”是通常采用的两种控制策略, 采用这种控制策略有望获得高精度的同步控制要求 7 。仿真中采用主从式同步控制, 把2#液压缸作为主液压缸, 5#液压缸作为从液压缸。以2#液压缸的输出为理想输出, 5#液压缸受到控制来跟踪这一选定的理想输出并达到同步驱动。图7为推进液压系统多缸同步仿真AMESim 模型, 图8则为采用Simulink构建的推进液压系统多缸同步仿真控制模型。仿真中所取参数与没有采取同步控制时相同, 并且两个液压缸的调速输入均相同。由于设定中所受负载以及液压缸的粘性摩擦系数不同, 导致推进过程中液压缸的推进速度和推进位移不同。此时, 把2# 和5# 两个液压缸的位移输入到AMESim的S函数中, 然后通过输出接口在Simulink中搭建控制模型进行仿真。仿真中把两缸的位移差与设定的位移进行比较, 所得的位移差信号反馈到调速设定值上, 进行补偿来达到同步控制。图9和图10为采用同步控制的液压缸推进压力和推进速度仿真曲线图。从图中可以看出, 两个液压缸所受压力与图3没有采用同步控制措施的推进压力曲线相比, 两者没有发生变化。但从图10可以看出,此时主从两个液压缸的推进速度基本重合, 稳定后的推进速度均为36mm /min。图11和图12为两个液压缸的位移仿真曲线和位移差仿真曲线图。由于2#液压缸的推进速度和5#液压缸的推进速度相同, 因此两个液压缸的推进位移很接近。从图12可以看出, 两个液压缸的推进位移差只有01025mm, 完全满足控制要求。4结论本文对推进液压系统的多缸推进进行了仿真分析, 比较了没有采用同步控制和采用了同步控制这两种情况下的仿真结果。仿真结果表明采用主从式同步控制策略能较好地实现推进系统的同步协调运动, 液压缸的同步精度可控制在1mm之间, 为实际盾构同步推进提供了参考依据。Ultra-high hydraulic angle O-ring seal the experimental studyCui Yutao Du CunchenAbstract : nitrile rubber O-ring EHV end Kok containers sealed imposed on containers so high hydraulic seal experimental series. The results show that angle enclosed structure, as well as O-ring compression rate, diameter, enclosed space, rubber hardness, The sealing surface roughness and seal the form and position tolerances, and other relevant factors reasonable match, strict control, the use of ordinary O-ring can be achieved 138MPa ultrahigh static hydraulic seal. Keywords : EHV static O-ring sealAlong with the rapid modern industrial development, UHP increasingly widespread use of the ultrahigh-pressure killing Hill, super-high-speed refrigeration, Expanded food industry, supercritical fluid extraction, low-salt treatment, Expanded room temperature and high pressure compression fermentation and other typical applications. Such equipment is produced by the many advantages of increasing peoples attention. If UHP food production is instantaneous pressure, role uniform, safe operation and low energy consumption to maintain good natural food color, smell and taste and nutritional characteristics of the components, with 21 new food simple, safe, natural, nutrition, health, and environmental protection in consumption demand. Which have significant social and economic benefits, has tremendous market potential and broad prospects for development. However, Chinas current UHP food production industries badly need to improve the level of equipment, can produce economic, Energy-saving, safe and efficient handling equipment constrains EHV food processing technology marketing major bottleneck. Among them, how to create economic EHV containers and ensure that the high pressure seal containers is particularly difficult lie. UHV equipment can operate normally sealed to a large extent depends on the integrity of the structure. High pressure sealing device about the weight of the containers, weighing 10% to 30%. and the cost accounts for 15% 40% of the total cost, design sealed pressure vessel design is an important component. Because many UHV equipment for space operations, the operation requires not only material can be quickly loaded fast again. and the frequent requirement in the open despite repeated achieve reliable sealing, General use of fast open-closed structure since the close of this problem can be resolved. Ordinary rubber O-ring seal structure is simple, convenience, low cost, compact installation, easy to use and has since closed closely role advantages, the industry is widely used. So experiment nitrile rubber (NBR) O-rings (32.5 specifications for the 3.55G. implementation of the standards for GB3452.1-92) Kok sealed experiments. 1 O-ring seal from the Principle1) state preload O-ring sealed site after its general section by a certain amount of compression, as O-rings have good flexibility, the interface will have a certain degree of contact pressure, thus achieving preload under seal. 2) state When the sealed chamber filled with hydraulic media, the role of media pressure, the O-ring to shift the low-pressure side, and the seal gap closed to live. With the increase of media pressure, the contact pressure has also been increasing, the peak is always greater than the fluid pressure. This will guarantee that the O-ring seal the sealing function, reflects the O-ring seal the ability to automatically sealed. Experience has shown that for ordinary rubber materials, generally 13 105Pa than the standard pressure. 2 the main parameters of SealO-ring seal effects and compression rate, diameter, enclosed space, rubber hardness, The sealing surface roughness and seal the form and position tolerances, and other factors are closely related. The impact of O-ring seal properties of various factors, as long as the parameters of a design will reduce the unreasonable results sealed, even result in seal failure. Now, therefore discuss the impact of specific factors to determine the value . 1）compression rateAfter the O-shape link loads the seal spot, its section generally receives a quota the compression, because the O shape link has the good elasticity, docking touches personally meets has the certain contact pressure, thus realizes under the pre- tight condition seal.2) active statusAfter the sealed chamber sufficiently enters the hydraulic pressure medium, in under the medium pressure function, the O shape link carries over a low pressure side, seals up the seal gap. Along with the medium pressure increase, the contact pressure also along with it increase, its peak value always is bigger than the fluid medium pressure. This has guaranteed the O shape packing ring seal function, also has reflected the O shape packing ring automatic sealing ability. The experience indicated that, regarding the ordinary rubber material, generally as the standard compares the pressure take 13105 P a.3) seal gapO-ring gap in the high-pressure easily deformed easily be squeezed into the sealed space in order to cause damage, it is necessary to the O-ring seal gap to be strictly controlled. To prevent O-ring extrusion occurred, and to take into account the difficulty of installing and dismantling, The experimental space for the sealing of 0.1mm.4) hardness Elastic modulus small O-ring, the maximum contact stress small, extrusion capacity, easy to destroy. So when a high pressure, high hardness should use the O-ring. In this experiment the O-ring hardness IRHD (International Rubber Hardness levels), 80 5.5) sealing surface roughness Seal the surface roughness is sealing technique to measure an important indicator. If the sealing surface Department has manufacturing defects or vertical scratch, it is very easy to seal leakage media. Ultrahigh Pressure Vessel Safety Technology Supervision provided EHV containers sealing surface roughness Ra should be less than or equal to 0 . 8 m. The experimental sealing surface roughness Ra from 0.4 m. 5) seals the form and position tolerances secret Sealed cylindrical surface of roundness, cylindricity tolerance by eight precision selection Hole-face vertical axis of tolerance by seven precision selection. 3 experimental devices and airtight structure （1）Experimental Device 1. Press flat under 2. Under plate 3. EHV four containers. 4.Pallets 5.O-ring 32.5 3.5 5-Ring 6.0 5.3 65 7. Cover 8. on the plate 9. Press plate 10. Stud 1 1. Arbors 12. Bolt 13. high-pressure pipe 14. connector nut 15. Nut (2) sealing principle When tighten bolts, which will help the upward movement of pallets compress O-rings, O-ring Close to the cone axis and the vessel wall. and the cone axis and the difference between forming ring seal belt, formed preload sealed. Operating in the state, with the media (the media to experimental pressurized water) pressure, the O-ring is compressed volume incr
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