沥青混凝土摊铺机作业速度研究

分析了中国目前沥青混凝土摊铺机工程条件下作业速度的现状,对驱动变量泵—马达系统的容积效率、机械效率以及与摊铺作业速度之间的关系进行了深入细致的研究,提出了摊铺机合理作业速度范围应是变量泵额定排量1/4以上的结论,并从工程施工条件和设计两个方面提出解决作业速度不合理的途径和方法。     

一种钻机用拖挂式机泵组的半挂车

针对国内外油田模块化钻机快速搬家的需要,研制开发出了一种新型的钻机用拖挂式机泵组.该机泵组不需要吊车的协助,仅通过牵引车就能够实现整台机泵组的移运,且移运快捷、迅速、费用低,是出国钻机配套机泵组的理想型式,也是国内外用户购买钻机时的首选型式.经过针对为适应低温工作条件而进行的设计和改装后,该机泵组还可在低温环境下使用.     

一种新型绿化喷洒车液位计的应用

设计了一种新型绿化喷洒车液位计,具有高、低位智能声光报警功能,在液体加注过程中能够避免罐体满溢,在车辆进行绿化喷洒作业过程中能够避免因液泵空转造成的液泵损坏。     

通航河道围堰施工安全作业技术

桥梁、泵闸、出水箱涵等工程经常需要在河道中进行围堰作业,对于通航河道来说,既要考虑到作业人员本身的施工安全,还要考虑过往船只的通航需要及通航安全。在施工前对这些安全措施进行充分考虑,对作业技术进行深入研讨和优化,可以大幅度地提高施工安全系数,确保通航要求。该文对常用的通航河道水上施工安全作业技术进行了介绍和分析。     

防尘堵的妙用

在检修液压制动装置时,更换制动分泵是经常要进行的作业项目.     

汽车栈桥应急控制改进

汽车栈桥作为连接渡轮和码头的唯一通道,是码头汽车滚装作业的核心设备,为了提高设备的应急操作能力,通过增设小流量泵组,并引入船电供电,将原有自动化运行过程分解为各机构的单动手动控制,实现应急情况下控制栈桥设备的应急操作,确保设备的有序运行。     

砼输送泵泵送压力损失原因分析

砼输送泵泵送压力的损失直接影响砼的可泵性 ,文中就砼输送泵泵送压力损失产生的原因 ,从泵送作业和理论上进行了分析     

离合器液压传动部爱排气方法的探析

在进行离合器的总泵或分泵维修作业时，经常会碰到液压油泄空的现象，这时候就必须进行补油排气。 一、传统的排气方法 1．给储油壶加足制动液到“H”线； 2．取下分泵放气螺塞的防尘帽，连续踩踏离合器踏板数下，在将踏板踩到底的情况下，松开排气螺塞，排出管路空气后，拧紧排气螺塞，松开离合器踏板；     

清防蜡方式组合实施经济效果分析

准东采油厂对火烧山、沙南两个作业区结蜡油井在坚持以油(水)热洗作业为主的前提下,辅之以自能热洗、机械清防蜡、油井电加热、化学清防蜡、微生物清防蜡、油井固体防蜡等清防蜡方式。该方式的组合实施,大大缓解了油井的蜡卡、蜡堵和油管结垢、腐蚀现象,提高了含蜡井的原油产量,既延长了油井热洗周期,降低了清防蜡成本,提高了清防蜡效果;同时也有效提高了泵效,延长了检泵周期,减少了蜡卡检泵维修作业井次,节约了井下作业成本,增加了企业效益。     

基于AMESim的高空作业车支腿液压系统仿真分析

以25米高空作业车支腿液压系统为研究对象,利用AMESim软件对支腿液压系统进行了建模、仿真,通过支腿液压系统的流量、位移等曲线分析了水平和垂直支腿的运动过程,同时研究了不同的泵转速对支腿液压系统伸缩效率的影响。仿真结果验证了支腿液压系对不同作业环境的适应性,达到了本车水平、垂直支腿均能单独控制的要求,同时也表明通过提高泵的转速,支腿液压系统的伸缩效率得到了优化,为类似车型的支腿液压系统的设计提供了参考。     

采用车厢底部出风的变频热泵空调在低温地区大巴车辆上的应用研究

纯电动大巴空调冬季制热是目前行业普遍关注的焦点问题,受大巴空调厂家技术影响,大部分电动空调热泵制热在环境温度0℃左右将无法启动,所以目前行业冬季制暖主要采用燃油炉或PTC加热方式。燃油炉与PTC加热能耗高,严重影响整车续航里程。热泵大巴空调可实现-15℃正常热泵制热,补气增焓技术可实现-25℃正常热泵制热。另外,在冬季制热时,暖风从上部的风道往下吹,大部分热风下不去,造成了车厢上部温度高,脚部温度过低,非常影响舒适性。通过从上部风口引一些风道到脚部的方式,提高车厢底部的热风循环,提高车厢热泵制热的舒适性,从而验证了大巴车厢底部出风对热泵空调制热效果的影响。综合上述,对热泵空调在低温地区冬季热泵制热效果及节能效果进行对比测试,通过对比热泵空调和电加热器的温升速率、耗电量和舒适性等参数,可得知热泵空调升温速度快、温控精度高、耗电量少,变频热泵空调更舒适、更节能。     

汽车发动机机油泵的综合性能评价

为了提高车用发动机润滑系统中的机油泵的研究和设计水平,对机油泵的主要性能指标进行了讨论,分析了不同类型机油泵的特点和发展趋势。结合作者近期生产实践和试验研究中的一些工作,分析了车用发动机机油泵试验台的架构、功能及典型试验结果。以目前各国的文献成果为依据,综合研究了排量、容积效率、压力波动等性能指标的影响因素及相互联系。通过试验台的测试实例论证了机油泵振动和噪声的测试方法和分析手段。结果表明：定排量机油泵无法满足发动机节能减排的要求,必须进行变排量泵的研发;基于完全空化模型的数值模拟方法是分析机油泵空化现象的有效手段;机油泵的振动和噪声性能受到压力波动和机械啮合的双重影响,必须综合考虑。     

底部加油油罐车管路结构探讨

底部加油油罐车在国内尚处于推广实施阶段,用户反映因附件密封不严或老化而产生油品的渗漏现象。而目前国内的底部加油油罐车管路结构主要有配置车载油泵和不配置车载油泵两种,根据实践经验,采用增加一个直通球阀或三通球阀的结构,可以有效防止油品渗漏。     

机油泵测试台的研制

针对电源车在大修时无法对机油泵进行检测的情况,采用计算机测试系统实现了对机油泵机油压力、机油温度、油泵转速等参数及其关系的测试与分析,为维修机油泵提供了可靠的依据,文中对机油泵测试装置的主要组成、工作原理、数据采集和处理方法作了详细论述,对其他类似装置的检测和测试也有一定借鉴作用。     

天然气汽车使用中存在的问题及对策

阐述了天然气汽车功率下降和早期磨损的原因。介绍了提高天然气汽车功率的措施，即提高发动机的充气系数，适当提高发动机的压缩比及使用专用天然气汽车发动机润滑油。试验表明，使用专用发动机润滑油对提高发动机功率和防止早期磨损具有显效果。     

Optimized dynamic battery model suited for power based vehicle energy simulation

Ever increasing demand for the petroleum is causing faster than expected oil shortages in the supply and demand balance around the world and furthermore, many specialists in the field of oil production such as Association for the Study of Peak Oil and World Energy Outlook are claiming that the petroleum is around the peak of its production (Figure 1). Such shortage made the greatest impact on the gasoline price hikes at the gas pump and thus, this impact was felt by the consumers severely and became the greatest motivation for automotive industries to strive to pioneer the researches for the next generation vehicle configurations ranging from HEV, PHEV, Pure EV to FCHEV (collectively noted as xEV). While the great deal of researches has been carried over the last few decades, it is still far from mass productions for consumer use except for the HEV mainly due to the high cost involved with other types of xEV configurations. Therefore, it is critical to design the vehicle to maximize the use of each component at its highest point regardless of any cost scenarios and it is clear that this optimization can only be achieved through the accurate energy balance simulation for a specific target vehicle prior to the actual hardware implementation. In this paper, it is our intention to introduce modified dynamic battery modeling scheme that would provide a more accurate way of simulating the battery behavior when used in the vehicle energy simulation system. Starting from a typical battery dynamic model to predict the voltage given an imposed current request, we have introduced a new scheme to establish the relationship between the voltage and the power (rather than the current) requested by the vehicle simulation system. The proposed scheme handles the power request from the vehicle simulator considering the dynamic battery characteristics and in turn, contributes to the better estimation of the current integrated energy usage and battery SOC level in the given battery dynamic system used in the vehicle energy simulation system.     

Thermal anaysis of an electric water pump for internal combustion engine vehicles

An electric water pump for engine cooling system has an advantage which particularly in the cold start, the use of the electric water pump saves fuel and leads to a corresponding reduction in emissions. However, the electric water pump for internal combustion engine generates much more heat loss than that for hybrid electric vehicle or electric vehicle since it is operated by electric power of high current and low voltage. In this study, the fluid flow and thermal characteristics of the canned type electric water pump with an inverter integrated has been investigated under the effects of heat generation. The analysis conditions such as outdoor air temperature of 125°C, water pump speed of 6000 rpm, coolant temperature of 106°C and coolant flow rate of 120 L/min were used as a standard condition. Therefore, the thermal performance of the canned type electric water pump’s motor and inverter was evaluated by comparison with that of mechanical seal type. In the motor, the temperature reduced by over 10°C, and in the inverter, the amount of temperature decrease equaled to the maximum temperature difference, about 18.7°C. Also, canned type electric water pumps of variable materials were compared for the evaluation of thermal transfer performance for variable thermal conductivity of a can. The motor and inverter were cooled lower to 42°C at motor and about 40°C at inverter for reasonable selection of can’s thermal conductivity.     

Influential factors for HLA pump up in a roller finger follower engine

In an HLA (hydraulic lash adjuster) piston engine, “pump up” can occur when a valve is opened by the HLA when it should be closed. HLA pump up is more frequently encountered with exhaust valves than with intake valves. When HLA pump up in occurs in the exhaust valve, exhaust gas from the exhaust manifold enters the cylinder on the intake stroke, and fresh air-fuel mixture exits through the exhaust manifold on the compression stroke and is burned in the catalyst, causing partial burning, misfire, catalyst melting and power drop. HLA pump up occurs when the force on the valve from the HLA is higher than the force on the HLA from the valve. HLA pump up is related to design parameters, such as oil pressure, rocker ratio, spring load, spring surge, and both intake and exhaust valve timing. In this study, valve lift and load on a roller finger follower were measured at varying engine firing conditions to evaluate HLA pump up. The results indicated that effective measures to reduce HLA pump up include a higher rocker ratio, a lower oil supply pressure to the HLA, a higher spring installation load and a lower spring surge.     

汽车油改气效果保障措施及方法

汽车油改气后会出现油气混烧、动力下降、加速性能差、气耗大、故障指示灯亮及回火放炮等不足或故障现象。采用正确加装点火提前角控制器及仿真控制器,选用合适的火花塞、进行功率阀及怠速阀的调整等方法,可以有效地克服天然气汽车改装后的不足,消除各种故障,是保障汽车油改气效果的必要措施。     

柴油机用动力转向泵的匹配

介绍柴油机转向泵的匹配设计方法,并以此为实例进行说明;通过实车转向力、压力损失和转向油温的测试来验证匹配效果;最后阐述系统管理对维护转向泵性能的重要性。