液压系统管路漏油原因探讨及对策

液压系统中使用的管路种类很多,根据液压系统的工作压力及安装位置的不同,选用的有钢管、紫铜管、橡胶管、尼龙管和塑料管等。这些管路一旦损坏漏油,轻则污染环境、影响系统功能的正常发挥,重则危及安全。本文分析归纳了造成液压管路漏油的原因及采取的相应对策。1漏油的原因分析1.1管路质量差在维修或更换液压管路时,如果在液压系统中安装了劣质的管路,由于其承压能力低、使用寿命短,使用时间不长就会出现漏油。硬质油管质量差的主要表现为管壁厚薄不均,使承载能力降低;劣质软管则主要是橡胶质量差、钢丝层拉力不足、编织不均,使承载能力不…     

工程机械常用卡箍的技术特点及选用探析

工程机械中的管路系统,如进气系统、排气系统、散热系统、燃油管路、液压系统、中冷管路等,都大量使用卡箍.介绍各种卡箍的技术特点,指出根据不同管路系统的特点及使用环境选用不同种类的卡箍,可以提高系统和管路的可靠性,从而有效控制漏油、漏气、漏水故障的发生.     

工程车辆全动力制动系统液压管路建模与仿真

针对全动力液压制动系统管路布置对整车制动性能影响较大的问题,用键合图方法建立了全液压制动系统液压管路的数学模型,在建模过程中考虑了液压管路的动态摩擦阻力。应用Matlab软件中的动态仿真工具Simulink软件包对液压管路的动态特性进行了仿真分析,为研究和减小管路布置对全液压制动系统制动性能的影响提供了参考。     

液压系统管路防爆阀原理分析及应用

针对重型平板车上多种悬挂液压系统管路防爆阀的基本结构、工作原理以及典型运用进行分析,对不同类型的管路防爆阀的功能进行比较,指出在液压系统设计选型时应注意的问题,为正确使用提供了切实可行的方法,提高了平板车悬挂系统的可靠性。     

码坯机液压系统污染的防控

介绍了液压系统管路中污染物的种类,污染物的来源与危害。并根据在制砖企业码坯机液压系统现场布管安装管理中的经验,介绍码坯机液压管路清洁度在现场布管安装中的控制。     

一种带有优先阀的新型多路换向阀

近年来工程机械及叉车在转向系统中普遍采用了负荷传感液压转向器和优先阀。这种负荷传感系统具有液压系统效率高、功率损失少、转向系统油温低等特点。但是,它本身也存在一些问题,如液压管路多、总体布置不够方便等。为了克服上述问题,新近又出现了一种带有优先阀的多路换向阀。它将原来在液压系统中单独布置的优先阀并入多路换向阀机体内,从而减少了液压管路及管路损失,成为一种较理想的液压元件。     

卡套式接头与高压软管接头

我厂W2-100型全液压挖掘机液压系统管路采用卡套式接头和高压软管接头,工作压力为320公斤/厘米~2,通过几年来的实践证明这两种接头方式是好的,现分别介绍如下: 一、卡套式接头 1.要求:管路接头是挖掘机液压系统中的重要组成部分,根据挖掘机的使用条件,管路接头必须满足以下要求: (1)在320公斤/厘米~2压力下工作时,保证有可靠的密封性。 (2)在320公斤/厘米~2压力下具有良好     

Q2—8型液压汽车起重机故障排除实例

我公司一台Q2—8型液压汽车起重机,在使用过程中,液压系统发生故障。系统压力升不高,吊重无力。其原因可能有以下几点: (1)油箱液面过低或吸油管堵塞; (2)压力管路和回油管路串通或元件泄漏过大; (3)液压系统溢流阀开启压力过低; (4)油泵排油量不足; (5)油泵损坏或渗漏过大。 1 溢流阀开启压力过低分析根据以上五条,进行了系统检查,经查液面并不低,而且压力能达到17MPa,说明吸油管路并不存在堵塞现象.该液压系统为开式串联     

高耸泵管的清洗

高层建筑工程中使用泵送混凝土时,需要有一个有效的管路清洗方法。在工地上设置独立清洗站便于管路的清洗并能简化废混凝土的处理。使用连到一短段清洗管路上的液压转化阀,可以把一次浇注后留在管路中的混凝土直接送到停留的运送车中。     

基于AMESim仿真的贴面热压机管路液压冲击研究

某型号贴面热压机在工作过程中出现液压冲击现象,为此,在不改变液压系统结构的条件下,考虑通过延长阀口的关闭时间来减弱液压冲击。利用AMESim软件建立液压管路仿真模型,保持管路长度不变,设置阀口关闭时间,比较不同时间下液压冲击的变化规律。改变管路长度,设置阀口关闭时间,比较不同管路长度下液压冲击随时间变化的规律。研究结果表明,当管路长度小于10 m时,在10～100倍相长的阀口关闭时间内,液压冲击减弱效果明显,液压冲击下降到相同水平,但长管路需要更长的阀口关闭时间。     

温度对吸油毡吸油性影响试验研究

分别利用低温和高温环境试验箱严格模拟环境温度,在不同温度环境下测试四种常用吸油毡对三种渤海原油的吸油性。试验同时测定三种原油的凝点,用于探索油品凝点对吸油毡吸油性的影响。试验结果表明:被测试的十二组吸油过程均属于物理过程,提出的关于吸油毡表面黏附和渗透作用的数学模式能较好描述这些过程;对于这三种原油而言,渗透吸油作用在冬季只适合于绥中原油;另外,吸油毡对三种原油,即使在夏秋季也无法达到最大吸油性;黏附和渗透吸油倍数同原油凝点以及吸油毡类型有关。四种吸油毡中,MXU1000系列的吸油性最好,羊毛毡的吸油性最低。     

Experimental Study of LNAPL Migration in the Vicinity of a Steep Groundwater Table

Migration of Light Non-Aqueous Phase Liquids (LNAPLs) in porous soils was studied experimentally, using one-dimensional and two-dimensional laboratory tests. The movement of crude oil under constant pressure was observed in vertical and horizontal transparent columns filled with sand. It was found that in both cases the average oil saturation does not change during the oil propagation. Its value depends on the initial water saturation in sand and the mobility of air in front of the oil front. The hydraulic conductivity to oil was found to be constant along the vertical column, while it decreased exponentially when oil was spreading along the horizontal column. Two-dimensional experiments were carried out in a sand tank with simultaneous water flow and the oil migration. Oil leaked into the sand from a thin feeder above the water table with constant oil level. The experiments were conducted with three types of LNAPL: crude oil, vegetable oil, and engine oil. Evolution of the oil mound was recorded through the transparent front wall of the sand tank, while the water table was monitored using a series of piezometers. Presence of the water table had a major effect on the oil mound shape and size. Downwards movement of the oil front slowed down around the top of the capillary fringe and completely stopped near the water table. The depth of penetration into the capillary fringe depended on the oil viscosity and the pressure at the oil source. Lateral spreading was more pronounced in the direction of the water movement.     

一种改进的油浸式变压器排油注氮灭火装置

介绍了油浸式变压器排油注氮灭火装置的工作原理,描述了基于重锤机构传统的排油注氮灭火装置存在的不足。针对传统的排油注氮灭火装置的不足,提出了一种基于气动的排油注氮灭火装置的设计方案。采用气动球阀作为排油阀和注氮释放阀,解决了排油注氮灭火装置容易渗油和渗氮的问题。采用气动和电动组合控制模式,有效降低了排油注氮灭火装置误动风险。在排油管路增设密封膜片,有效保障了排油管路的密封性,同时可实现系统有效模拟运行,提高了油浸式变压器排油注氮灭火装置运行的安全性和可靠性。     

全户内变电站的油坑及油池设计探讨

根据相关规范规定,确定了全户内变电站油坑及事故油池的设置要求,通过浙江沿海地区一座变电站算例,对比分析了20%设备油量贮油坑容积和100%设备油量贮油坑容积两种方案,得出了有效的推荐方案结论,指出方案选择时,应该根据工程站址情况及地质情况,综合考虑选择贮油坑容量并合理布置结构形式,有条件地设置事故油池。     

The Treatment of Weathered Crude Oil in Kuwait

During the Gulf War about 740 oil wells were blown up by the Iraqi forces, and the unburnt oil flooded from these wells to form oil lakes. This resulted in one of the largest oil slicks in the world, causing serious damage to the marine life in the Gulf region. The oil which is exposed to atmospheric weather over a period is called 'weathered crude oil feed stock', and it is important to treat this oil not only from the economical point of view but also to consider the environmental pollution which is created. The Government of Kuwait, represented by Kuwait Oil Company (KOC) has made its best attempts to treat this oil, and most of the oil lakes have now been cleared. The objective of this study is to report and evaluate different treatment methods and measures to control and manage these oil lakes.     

Environmental impact of used motor oil

The information concerning the effects of used motor oil on the environment is reviewed. The production and fate of used motor oil are analyzed and the effects on soil and aquatic organisms are described. The combustion of waste crankcase oil, with particular reference to environmental impact, is discussed. The mutagenic and carcinogenic effects of used motor oil are described. Information on the biodegradation of lubricating motor oil is also reviewed. The available information shows that used motor oil is a very dangerous polluting product. As a consequence of its chemical composition, world-wide dispersion and effects on the environment, used motor oil must be considered a serious environmental problem.     

初始油面温度对水成膜泡沫铺展特性的影响研究

为探究高温油面对水成膜泡沫的影响,利用自主搭建的铺展特性测试实验平台获得水成膜泡沫在不同初始温度KI25X变压器油面上的铺展参数,对比水成膜泡沫在两种油池尺寸（D=50 cm和117 cm）下不同温度油面的铺展行为,分析铺展面积和铺展速率随初始油面温度的变化规律。结果表明：D=50cm油池,铺展形状呈现中心对称,铺展速率存在快速增长、线性增长和缓慢增长3个阶段;D=117 cm油池,铺展形状呈现不规则特征,仅有线性增长和缓慢增长两个阶段;初始油面温度显著影响水成膜泡沫的铺展特性,D=117 cm时,铺展速率随油温增加先上升后下降,在初始油面温度60℃时,平均铺展速率达到最大;基于油面铺展理论基础,建立了铺展速率计算模型,得到泡沫摩擦力参数随油温增加呈现先上升后下降的变化规律。     

水雾在扑灭大型工业燃油炊具油池火的应用

大型商用燃油炊具面积巨大，并涉及到大量热油，灭这种大型商用燃油炊具火灾非常困难。利用水雾系统对大型商用燃油炊具保护进行了研究，从理论和试验对水雾系统的灭火机理以度扑灭大型油池火灾需要达到的相关标准进行了研究。根据灭火机理和相关标准，设计了两套水雾灭火系统，进行了一系列的实体火灾试验。研究表明，两套水雾灭火系统成功地扑灭了大型油池火灾，有效预防了复燃。其灭火性能取决于水雾系统类型、喷射压力以及炊具罩的位置。     

The fate of oil and oil—dispersant mixtures in freshwater ponds

The fate, distribution and composition of oil and oil—dispersant mixtures were studied in a series of five, lined, inground ponds containing sandy gravel sediment and mesotrophic water. Norman Wells crude oil and Corexit 9527 were added at nominal concentrations of 100 and 20 ppm, respectively, to two of the ponds, and the crude oil alone was added at 100 ppm to a third pond. The water surface, water column, the sediment, pond liner and attached biota were systematically sampled for a year. While only about 2% of the oil remained in the water column of the pond with no dispersant addition, in the pond with the dispersant, about 10% of the oil persisted in the water for several weeks. Most of the oil initially dispersed in the water returned to the water surface, then eventually sank to the sediment. Thinner surface films showed a higher dispersant content than the thicker slicks, and the thinner films had higher infrared carbonyl absorption. Final distribution calculations revealed that about 45% of the oil had degraded in the oil—dispersant-treated ponds during the one year study, while only 23% could not be accounted for in the oil pond. Changes in the oil composition during the experiment were similar in all ponds, with no evidence to suggest that the dispersant affected oil composition in any special manner.     

地层条件下凝析气藏的多相渗流特性

 在进行凝析气藏的数值模拟、试井分析以及开发动态预测的过程中,需要获取具有代表性的凝析油气、油水和气水相对渗透率曲线。深层高温高压凝析气藏在开采过程中地层流体渗流伴随着复杂的相变,因此,不能用传统的油气相渗曲线来代替实际地层条件下凝析油气相对渗透率的变化规律。在地层常规物性和流体特性分析的基础上,以实际凝析气藏的凝析油、气和地层水为实验流体,用实际凝析气藏的岩石作为多孔介质,在地层温度和压力条件下研究了多相渗流特征,得到了油气、油水和气水多相渗流的相渗曲线,表明地层条件下低孔低渗岩石的油水、油气和气水两相共渗能力较弱,而对于含裂缝或孔洞的高孔高渗岩石,油水、油气和气水两相共渗区较宽,驱替效率较高。这些成果为高温高压凝析气藏的动态模拟与预测提供重要的数据和相渗曲线。