贯穿式旋片真空泵的性能计算与实验分析

介绍了贯穿式旋片真空泵的结构及工作原理,建立了贯穿式旋片真空泵的几何模型,讨论了贯穿式旋片真空泵泵腔型线的建立以及工作腔的容积计算,精选了贯穿式旋片真空泵的性能计算,包括抽速、极限真空度以及真空度与时间的关系。最后测试某一贯穿式旋片真空泵的抽气性能,将测试值与计算值进行对比分析,验证了建立的贯穿式旋片真空泵性能的计算方法。关于贯穿式旋片真空泵的几何分析以及抽气性能的计算,对贯穿式旋片真空泵的设计分析具有一定的参考意义。     

油扩散泵主要故障的修复方法

油扩散泵是一种高真空泵,全名叫扩散式蒸气流泵,是以机械泵作为前级泵,连续地抽除密封容器中的空气和其他对金属泵体及泵油不起作用的气体,从而获得高真空的设备,它的极限压强可达L×10~2～1×10~7Pa,抽速     

变频器在电力变压器汽相干燥罗茨泵真空机组控制中的应用

电力变压器煤油汽相干燥设备工艺要求真空度比较高,为保证罗茨真空泵能达到较高真空,就必须设置罗茨泵真空机组。在我们的煤油汽相干燥设备应用变频器控制真空机组大、小罗茨泵,可以有效的缩短了设备抽真空的时间,保护了罗茨泵,提高产品质量。     

ZRW6-70×110型高纯铝箔真空热处理炉

高纯铝箔真空热处理炉是由沈阳市机械工业管理局主持于1992年8月27日通过鉴定。该设备主要用于处理电容器生产用的铝箔,它能脱去紧密缠绕的铝箔表面的油类杂质,并在真空状态下进行热处理使铝箔不氧化,使电容器的质量大大提高。由于该设备极限压力低,抽速大,真空机组极限压力优于6×10~(-2)Pa,主泵     

基于泛函的通用涡旋型线涡旋式滤油机真空泵三维建模及动态仿真分析

在涡旋式滤油机真空泵涡旋型线设计中,利用基于泛函的通用涡旋型线设计理论,对涡旋式滤油机真空泵运转机理进行了分析,利用工程分析软件PRO/ENGINEER建立了通用涡旋型线涡旋式真空泵零部件三维实体模型并进行了整机装配,运用PRO/ENGINEER动态仿真模块进行了涡旋式滤油机真空泵整机运动仿真,利用其放大功能,在放大几万倍的条件下,啮合点仍然保持正确接触,且在动态模拟仿真过程中运转正常,证明了通用涡旋型线理论和求解建立模型过程的正确性,为通用涡旋型线涡旋式真空泵的结构设计提供了依据,拓宽了单一涡旋型线设计理论与方法研究的思路。     

真空泵修理

2X型是一种油封式双叶片真空泵.它的抽气速率为0.2～150L/S,真空度能达到1～10~(-2)Pa。它用于厂矿的真空设备上,并单独将此泵用于设备上抽真空,也有作为高真空扩散泵和罗茨增压泵的前级泵。我厂真空设备都用2X型真空泵,下面介绍修理方法。     

几种高真空泵机组简介

目前,高真空度越来越多地应用到一些精密分析仪器中,了解各类泵的性能特点及其形成真空度的原理,有助于帮助正确选型,合理组合,从而达到所需各种真空度要求。同时,在获取真空度的过程中,设备的操作维护特别重要,必须严格按程序操作。下面介绍几种真空泵及其组合。１．２Ｘ型旋片式真空泵用于密封容器抽除气体获得真空的基本设备。该泵设有气镇装置,可抽除含有流量可凝性蒸气的气体。广泛用于试验室抽滤和分离。使用时可根据需要在进口处加装电磁压差真空阀,当泵突然停止运转或电源突然中断时,会自动封闭真空系统,并将大气放入泵…     

高真空液环式泵的设计

提出了一种新型的两级单作用液环真空泵的设计方法。性能试验和实际运转试验表明,吸入真空度可达50hPa,最大抽气量为1700m^3／h,真空泵抽气量大、极限真空度低,从而拓展了国内两级单作用液环式真空泵的应用范畴。     

冻干设备真空系统设计及其节能运行控制方式的应用研究

介绍了SZDG200冻干设备真空系统设计,系统中真空机组选用罗茨泵 罗茨泵 水环泵(带大气喷射泵)三级真空泵组;在干燥仓设一电动调节充气阀,通过控制干燥仓内充气量来控制干燥仓内的压力;采用预抽真空机组和维持真空机组组合的方式实现真空机组节能控制运行.实际工程应用表明,该真空系统能较好的满足冻干生产需要.在进行冻干小葱实验时,真空机组采用节能控制运行方式比普通运行方式可节能27%,节能效果明显.     

一种新型电磁真空泵的优化设计

针对传统膜片式真空泵质量大、成本高的缺点,提出了一种由电磁执行器直驱的两级串联膜片式真空泵,并验证了其具有良好的抽气性能。利用Matlab/Simulink建立了电磁真空泵的仿真模型,结合仿真模型分析及样机性能测试,确定模型参数,验证了模型准确性;结合插值法与有限元法建立了簧片阀刚度和结构参数之间的关系式,并根据簧片阀结构建立了等效质量和结构参数之间的关系式;在此基础上,以真空度最大为目标,利用遗传算法进行簧片阀组的协同优化。结果表明:电磁真空泵样机优化后抽气性能提升了37%,优化后的抽气性能良好,30s内真空度可达66.9kPa,为后续电磁真空泵的研究提供了参考。     

中浓纸浆泵运行性能试验研究*

中浓纸浆泵是中浓输送环节的核心设备,其运行性能直接影响着输送系统的效率。为了研究不同运行条件对中浓纸浆泵运行特点和性能的影响,设计一种基于声纳流量测试系统的中浓纸浆泵性能试验台。研究分析了纸浆浓度(质量分数)为7.52%, 9.3%, 12.1%,转速为960 r/min, 1 140 r/min, 1 500 r/min和不同排气抽吸真空度时,泵的扬程、效率、出口含气率及最大极限流量变化特征。试验结果表明：随着纸浆浓度的增加,同一流量下扬程、效率逐渐下降。真空度对泵的性能特性有显著的影响,在不抽真空条件下,中浓纸浆泵可实现7.52%浓度纸浆的输送,但随着流量的增加,扬程、效率明显下降;随着抽吸真空度的增大,扬程逐渐升高,且存在一个最佳真空度值使得泵效率最高,泵出口纸浆的含气率逐渐降低。扬程随转速的增加而升高,泵出口纸浆的含气率降低;所需真空度随转速的增加而减小,表明提高泵转速有利于纸浆中气液的分离从而降低所需的真空度值。泵出口纸浆中含气率随着纸浆浓度的增加而升高,同时所需的抽吸真空度也迅速增加。最大流量极限值随着纸浆浓度的增加而减小,随转速的增加而增加。     

重卡电动泵吸油阀的改进设计及仿真分析

目前重卡电动泵吸油阀大多采用结构简单的球阀结构,导致泵产生反冲流量过大和容积效率低的缺陷。为此,利用滑阀和锥阀的优点,提出了采用滑锥阀结构改进设计吸油阀的技术方案。通过建立吸油阀、电动泵及其液压举升系统的AMESim仿真模型,在吸油阀流量特性、泵的出口压力和液压缸举升速度方面进行了动态性能仿真,并与球阀结构的电动泵进行了比较分析。结果表明:该技术方案有效且可行,能有效降低泵的反冲流量和提高泵的容积效率,可为高性能重卡电动泵的研制提供理论参考。     

适用于7．2kW空调机的高效节能压缩机

通过对压缩机泵体结构的进一步优化以及电机的槽型改善，提升了高效压缩机的整体能效水平。重点进行泵体吸排气机构和机械摩擦的分析，提出降低吸排气阻力和降低机械摩擦损失的方案，对电机进行根本的改善设计，从而提升压缩机能效。     

爬壁机器人滑动式负压吸盘吸附特性的实验研究

针对一种带有滑动式负压吸盘爬壁机器人的吸附特性进行了试验研究，通过测试吸盘在风机突然开启、突然关闭以及遭遇壁面缝隙发生泄漏3种情况下的负压响应曲线，分析并绘制了风机吸盘系统的工作特性曲线，建立了吸盘内负压模糊控制系统，为吸盘的结构设计和负压控制提供了依据。     

轴向柱塞泵低气压运行特性建模与试验分析

空化是影响液压系统动态特性的重要因素,为此开展了轴向柱塞泵低压环境下的工况研究。考虑气液两相混合油液的密度、体积弹性模量和黏度的影响,限制入口油腔的最低压力,建立轴向柱塞泵的压力流量模型,计算获得轴向柱塞泵在不同工况下的流量特性,并通过试验验证。研究表明:负载增大导致更严重的空化以及泄漏,并使容积效率降低;轴向柱塞泵在达到临界流量之后,转速提升只会加剧空化,而不能提升流量;最大容积效率出现在临界流量产生之前。为轴向柱塞泵低气压性能预测提供了理论支撑。     

一种仿生型无阀压电泵

针对传统的容积型流阻差式无阀压电泵具有吸入周期和排出周期,存在着流动脉动大、流量小的问题,提出一种新型的鱼鳍摆动式无阀压电泵。模仿在鱼类中巡游速度最快的金枪鱼的鱼体结构,设计了压电双晶片结构的压电振子,并将其尾鳍设计成柔性叶片状。分析了压电双晶片结构悬臂梁的受力变形、模态振型在机电转换效率方面的关系。研制了泵的样机并测量了激励电压在100 V时泵的流量。实验结果表明:振子工作在1阶振型时,泵水效应不明显;振子工作在2阶振型时,谐振频率为740 Hz,泵的流量为266 mL/min;振子工作在3阶振型时,谐振频率为1 280 Hz,泵的流量为105 mL/min。     

Adsorption Performance of Sliding Wall-Climbing Robot

Sliding wall-climbing robot(SWCR) is applied worldwide for its continuous motion,however,considerable air leakage causes two problems:great power consumption and big noise,and they constraint the robot's comprehensive performance.So far,effective theoretical model is still lacked to solve the problems.The concept of SWCR's adsorption performance is presented,and the techniques of improving utilization rate of given adsorption force and utilization rate of power are studied respectively to improve SWCR's adsorption performance.The effect of locomotion mechanism selection and seal's pressure allocation upon utilization rate of given adsorption force is discussed,and the theoretical way for relevant parameters optimization are provided.The directions for improving utilization rate of power are pointed out based on the detail analysis results of suction system's thermodynamics and hydrodynamics.On this condition,a design method for SWCR-specific impeller is presented,which shows how the impeller's key parameters impact its aerodynamic performance with the aid of computational fluid dynamics(CFD) simulations.The robot prototype,BIT Climber,is developed,and its functions such as mobility,adaptability on wall surface,payload,obstacle ability and wall surface inspection are tested.Through the experiments for the adhesion performance of the robot adsorption system on the normal wall surface,at the impeller's rated rotating speed,the total adsorption force can reach 237.2 N,the average effective negative pressure is 3.02 kPa and the design error is 3.8% only,which indicates a high efficiency.Furthermore,it is found that the robot suction system's static pressure efficiency reaches 84% and utilization rate of adsorption force 81% by the experiment.This thermodynamics model and SWCR-specific impeller design method can effectively improve SWCR's adsorption performance and expand this robot applicability on the various walls.A sliding wall-climbing robot with high adhesion efficiency is developed,and this robot has the features of light body in weight,small size in structure and good capability in payload.     

Output characteristics of a series three-port axial piston pump

Driving a hydraulic cylinder directly by a closed-loop hydraulic pump is currently a key research area in the field of electro-hydraulic control technology,and it is the most direct means to improve the energy efficiency of an electro-hydraulic control system.So far,this technology has been well applied to the pump-controlled symmetric hydraulic cylinder.However,for the differential cylinder that is widely used in hydraulic technology,satisfactory results have not yet been achieved,due to the asymmetric flow constraint.Therefore,based on the principle of the asymmetric valve controlled asymmetric cylinder in valve controlled cylinder technology,an innovative idea for an asymmetric pump controlled asymmetric cylinder is put forward to address this problem.The scheme proposes to transform the oil suction window of the existing axial piston pump into two series windows.When in use,one window is connected to the rod chamber of the hydraulic cylinder and the other is linked with a low-pressure oil tank.This allows the differential cylinders to be directly controlled by changing the displacement or rotation speed of the pumps.Compared with the loop principle of offsetting the area difference of the differential cylinder through hydraulic valve using existing technology,this method may simplify the circuits and increase the energy efficiency of the system.With the software SimulationX,a hydraulic pump simulation model is set up,which examines the movement characteristics of an individual piston and the compressibility of oil,as well as the flow distribution area as it changes with the rotation angle.The pump structure parameters,especially the size of the unloading groove of the valve plate,are determined through digital simulation.All of the components of the series arranged three distribution-window axial piston pump are designed,based on the simulation analysis of the flow pulse characteristics of the pump,and then the prototype pump is made.The basic characteristics,such as the pressure,flow and noise of the pumps under different rotation speeds,are measured on the test bench.The test results verify the correctness of the principle.The proposed research lays a theoretical foundation for the further development of a new pump-controlled cylinder system.     

THEORETICAL AND EXPERIMENTAL STUDY ON THE PRESSURE AND VACUUM CONTINUOUS CONTROL SYSTEM BASED ON HYBRID PUMP

A novel pressure and vacuum continuous control system, which adopts a hybrid pump as pressure and vacuum source, is presented. The mathematical model of the system is developed. The theoretical simulation and analysis on the system are implemented in order to study the relationships among the characteristics, parameters and working points of the system. The experimental investigations on the system characteristics are presented with the adoption of a fuzzy-PID controller. The simulation and experimental results indicate that the pressure and vacuum continuous control system based on hybrid pump has good dynamic and static performance, strong robustness and satisfactory adaptability to various system parameters. According to the results, system can successfully gain high accuracy and fast response signal. Also, the mathematical model of system is also testified by the experimental results.     

直线压缩机油泵系统仿真与实验研究

直线压缩机是一种新型的高效压缩机,传统的供油机构已经不再适用,为了开发新型供油系统,对一种利用压缩机机体振动来供油的油泵系统进行了仿真和实验研究.研究结果表明：这种油泵系统是行之有效的,其泵油量随机体振幅及振动频率的增大而增大;当机体振动一定时,泵油量随油泵固有频率的增大而减小,并未发生共振现象;系统阻尼与润滑油粘度有关,减小润滑油粘度可增加油泵系统的泵油量及效率;油泵的功耗影响着直线压缩机的效率,通过减小泵油高度、输油管道长度及壁面粗糙度,优化吸排油腔设计,以减小油泵功耗,从而提高直线压缩机效率.该油泵系统具有结构简单,体积小,效率高等特点,完全可以满足直线压缩机的需求.