REXROTH插装阀盖板LFA25WEA-7X/A10P10

REXROTH插装阀盖板LFA25WEA-7X/A10P10 R900912683，德国力士乐插装阀盖板，购买进口液压、气动、自动化控制工业配件，认准“上海韦米机电设备有限公司”，7年老店，保证产品原厂原装，价格优惠，售后无忧，欢迎新老客户咨询采购！
 
插装阀在液压系统中的应用.
插装阀具有内阻小，结构简单，工作可靠，标准化程度高，对于大流量、高压力、较复杂的液压系统可以显著的减小尺寸和重量等特点;而实心胎硫化机组液压系统工作时需要大流量、高压力油，因而，此系统可以应用插装阀满足要求。
一、
插装阀的工作原理及特点
插装阀是另一类液压控制阀的统称。其基本核心元件是一种液控型、单控制口的装于油路主级中的两通液阻单元(故又称二通插装阀)。将一一个或若干个插入元件进行不同的组合，并配以相应的先导控制级，可以组成插装阀的各种控制功能单元。比如方向控制功能单元、压力控制单元、流量控制单元、复合控制功能单元。
插装阀具有以下特点:内阻小，适宜大流量工作，阀口多数采用锥面密封，因而泄漏小，对于乳化液等地粘度的工作介质也适宜，结构简单、工作可靠、标准化程度高;对于大流量、高压力、较复杂的液压系统可以显著的减小尺寸和重量。
其结构:先导阀，控制盖板，插装件。
它是由插入元件、控制盖板、通道块三大部分组成。插入元件有阀芯、阀套、弹簧和密封件组成;控制盖板上根据插装阀的不同控制功能，安装有相应的先导控制级元件;通道块既是嵌入插入元件及安装控制盖板的基础阀体，又是主油路和控制油路的连通体。其中A、B为主油路通口，C为控制油路通口。A、B、C油口的压力和作用面积分别为PA、PB、PC和A1、A2、A3，A3=A1+A2， Fs为弹簧作用力。
二通插装阀通过不同的盖板和各种先导阀组合，便可构成方向控制阀、压力控制阀和流量控制阀。
1、插装阀构成压力控制阀
根据插装阀的工作原理当PAA1+PBA2 >PCA3+FS时，阀芯开启，油路A、B接通。插装阀C14，当电磁阀得电时，插装阀C14的C口直接通油箱，其C口压力为零。由此可知油路A、B接通，当A口的压力大于弹簧力的时候，系统压力油回油箱，所以此插装阀起溢流阀的作用，控制油缸径油口压力。
2、插装阀构成方向控制阀
由液压动作程序表可知，同时得电,来控制主油缸上行运动。当两者同时得电时插装阀C11、C13的C口通油箱PA>FS时,A、B口直接相通，油液可从A流向B口;当只有一个电磁阀得电时，主油缸下行运动。其中C13的PA<PB,阀芯开启，油液可从B流向A。此二处插装阀起到了单向阀的作用。
3、插装阀构成流量控制阀
在阀的顶盖上有阀芯升高限位装置通过调节限位装置的位置，便可调节阀口通流截面的大小，从而调节了流量。通过调节流量，可调节主油缸的下行速度。此插装阀作节流阀。
三、
插装阀在液压系统的简单应用，通过更为复杂的组合，可以实现更多的液压阀的功能。通过组合，插装阀可作为压力控制阀(顺序阀、减压阀)、流量控制阀(单向节流阀、节流阀)、方向控制阀(调速阀、液控单向阀、两位两通换向阀等)以及复合阀。


1、移架速度低已成为制约综采产量的-一个重要因素。为加快移架速度,在支架的液压系统中采用插装阀。插装式方向阀也是采用电磁阀作为先导阀，对主阀(锥阀进行先导控制,控制原理等同于电液操纵阀，但插装阀的通流能力(可达10000L/min以上大、响应快、工作可靠等突出优点，是管式阀无可比拟的，使其更适于在支架的电液控制系统中使用，而无需研制采用电磁先导控制的专用大流量主阀，既能满足使用要求,又可改善工作性能,提高通用化程度,从根本上解决由管式阀固有缺陷所产生的问题。
此外，采用插装阀设计支架液压系统还具有下列优势:
(1插装阀的优点十分适合支架的工况。液压支架的工况特点是:介质粘度低、工作压力高、流量大、工作环境恶劣、介质污染严重。插装阀的长处能得到充分发挥。
(2符合流体传动技术的发展趋势。为降低使用成本，消除环境污染，流体传动技术正向着使用纯水介质方向发展。液压支架是用同纯水性质比较接近的高水基乳化液作为工作介质，很有可能成为该技术发展成果的受益者,正趋向于采用纯水工作介质。由于水的粘度低，要求阀的密封性好,以提高系统的效率。插装阀采用锥面密封，具有优良的密封性能，更适于在纯水介质中工作，应作为纯水支架的首选阀种。
(3抗污染能力强、工作可靠。支架工作在采煤面，介质污染程度高，使阀芯磨损严重,缩短了阀的使用寿命，由此也导致了支架的各种故障，使工作可靠性降低，增加了维护时间，降低了工作面的生产率。插装阀的阀芯和阀套间无严格的配合要求，磨损轻，不易堵塞,也不会产生液压卡紧现象，在介质较脏时仍能保证支架液压系统正常、可靠地工作。
(4满足某些特殊工况的需要。如用于周期来压强烈的坚硬且难以冒落顶板的支撑式支架，在老顶突然来压时，立柱下腔控制阀中的安全阀，要通过很大的瞬时流量,普通安全阀的通流能力远不能满足通流要求，因而专门设计了充气式大流量安全阀，来适应这种工况。但该种阀的结构复杂，制造难度大，装配要求高,工作可靠性差，很难满足使用要求。而且，立柱下腔还要装设普通安全阀来适应正常工况的需要,这无疑会增加元件数量和制造成本。而采用插装式溢流阀，则能很容易解决这一难题,又会使系统简化。

2、工作原理分析
基于.上述分析,提出了用插装阀设计电液控制支架液压系统的设计思想和方案，其工作原理。该系统由电气和液压两部分组成,内储支架动作程序的微型计算机中央和支架控制器发出指令后，插装式方向阀中的电磁先导阀先动作,启闭相应的两通锥阀，接通或断开立柱或推移千斤顶的油路,使之按照-定顺序动作。立柱或推移千斤顶的工作状况由压力和位移传感器反馈到控制器，控制器根据反馈信号决定下一个动作。
由于中央控制器和支架控制器相互联网，故从中央控制器或各架的控制器都可以控制工作面任何--架支架的动作。
中央控制器的作用是控制和协调每台支架的控制器。此外，还能自动编程，修改系统参数,监测每台支架的工作状况,显示采煤机运行速度等。它可对支架的各个动作进行单独控制、顺序控制、成组控制和全自动控制。支架控制器通过插装式方向阀直接控制所在支架，同时将传感器采集的工况数据向其它支架和中央控制器发送。支架液压系统在接收到信号后，将完成下列动作过程:
(1升架立柱的动作由插装式方向阀8控制,当方向阀8中先导阀的电磁铁
1YA通电2YA断电时，该阀切换到左位,4个2通阀中的b和d的上腔通压力油,处于关闭状态,a和c的上腔通油箱,处于开启状态，泵站提供的压力液经2通阀c和液控单向阀，此时液控单向阀中的二位三通先导阀处于位置,工作同于普通单向阀中的2通阀进入立柱的下腔，立柱上腔的乳化液经方向阀8中的二通阀a回液，立柱伸出,实现升架。
立柱的无杆腔油路_上设有插装式液控单向阀和溢流阀组成的控制阀组，当顶梁接触顶板，立柱下腔的压力上升到泵站卸载压力时,液控单向阀关闭，支架达到初撑力;此后，随着顶板的下沉,使立柱下腔的压力上升到溢流阀的调定开启压力时，溢流阀开启卸载,立柱下腔的压力又降低，当立柱下腔的压力降低到溢流阀的闭合压力时，溢流阀又关闭。此后，将重复上述过程，使立柱下腔的压力在溢流阀的调定值附近变化，支架工作在恒阻支撑状态。由于插装阀的响应速度快，使立柱下腔压力变化小，支架的恒阻支撑性好,利于顶板的管理。
该系统在支架的升架过程中也实现了初撑、增阻和恒阻3个阶段，初撑力的大小由泵站压力决定,工作阻力的大小由溢流阀的调定压力决定。
(2降架当使插装式方向阀8中先导阀的电磁铁2YA通电,1YA断电时,该阀切换到右位,4个二通阀中的a和c的上腔通压力油，处于关闭状
态,b和d的上腔通油箱,处于开启状态，泵站提供的压力液经二通阀b进入立柱的上腔，同时将液控单向阀中的先导阀切换到右位，使其中二通阀的上腔通油箱,处于开启状态，立柱下腔的油液经液控单向阀中的二通阀回液，立柱缩回，实现降架。.降架结束后，将方向阀中先导阀置于图示中间阀位(1YA和2YA均断电，此时,4个二通阀的上腔均通压力油,处于关闭状态，立柱的两腔油路也均被封闭，支架停留在某一高度位置,准备移架。
(3推溜和移架推移千斤顶的动作由插装式方向阀9控制,当将方向阀中的先导阀置于右位(4YA通电,3YA断电和左位(3YA通电,4YA断电时时,分别控制着推移千斤顶活塞杆的伸出和缩回，实现推溜和移架。推移动作完成后，将先导阀置于中位断电,4个二通阀的上腔均通压力油,处于关闭状态，推移千斤顶的两腔油路均被封闭,推移动作停止。在接到新的指令后，支架将开始下一个动作循环。
当将方向阀中的电磁先导阀换成手动阀时，即能用插装阀设计现有手动控制方式支架的液压系统,以改善支架的工作性能、提高其工作可靠性。分析表明，用插装:阀设计的电液控制支架的液压系统，能满足支架的工作要求,基于同样的原理，可用插装阀设计出所有类型和型号的液压支架的液压系统。
REXROTH插装阀盖板LFA25WEA-7X/A10P10 R900912683
德国力士乐REXROTH插装阀盖板订货号和型号：
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二通插装阀是插装阀基本组件( 阀芯、阀套、弹簧和密封圈)插到特别设计加工的阀体内，配以盖板、先导阀组成的一种多功能的复合阀。因每个插装阀基本组件有且只有两个油口，故被称为二通插装阀，早期又称为逻辑阀。
1、二通插装阀的特点
二通插装阀具有下列特点:流通能力大，压力损失小，适用于大流量液压系统;主阀芯行程短，动作灵敏，响应快，冲击小;抗油污能力强，对油液过滤精度无严格要求;结构简单，维修方便，故障少，寿命长;插件具有一阀多能的特性，便于组成各种液压回路，工作稳定可靠，插件具有通用化、标准化、系列化程度很高的零件，可以组成集成化系统。
2、二通插装阀的组成
二通插装阀由插装元件、控制盖板、先导控制元件和插装块体四部分组成。图1是二通插装阀的典型结构
控制盖板用以固定插装件，安装先导控制阀，内装棱阀、溢流阀等。控制盖板内有控制油通道，配有一个或多个阻尼螺塞。通常盖板有五个控制油孔:X、Y、Z1、Z2和中心孔a。由于盖板是按通用性来设计的，具体运用到某个控制油路上有的孔可能被堵住不用。为防止将盖板装错，盖板上的定位孔，起标定盖板方位的作用。另外，拆卸盖板之前就必须看清、记牢盖板的安.装方法。
先导控制元件称作先导阀，是小通径的电磁换向阀。块体是嵌入插装元件，安装控制盖板和其它控制阀、沟通主油路与控制油路的基础阀体。插装元件由阀芯、阀套、弹簧以及密封件组成(图3 )。每只插件有两个连接主油路的通口，阀芯的正面称为A口;阀芯环侧面的称作B口。阀芯开启，A口和B口沟通;阀芯闭合，A口和B口之间中断。因而插装阀的功能等同于2位2通阀。故称二通插装阀，简称插装阀。

根据用途不同分为方向阀组件、压力阀组件和流量阀组件。同一通径的三种组件安装尺寸相同，但阀芯的结构形式和阀套座直径不同。三种组件均有两个主油口A和B、一个控制口x。
插装阀基本组件：1-阀套2-密封件3-阀芯4-弹簧5-盖板6-阻尼孔7-阀芯。

插装阀主要组合与功能
1、插装方向控制阀
插装阀可以组合成各式方向控制阀。
1)作单向阀
将x腔和A或B腔连通，即成为单向阀。连接方法不同，其导通方式也不同。若在控制盖板上如图5c连接一个二位三通液动换向阀，即可组成液控单向阀。
2)
作二位二通阀
二位三通阀，即可组成二位二通电液阀。
3)作二位三通阀
连接二位四通阀，即可组成二位三通电液换向阀。
4)作二位四通阀
连接二位四通阀，即可组成二位四通电液换向阀。
5)作三位四通阀0型换向阀
连接三位四通阀换向阀和单向阀，即可组成三位四通阀中位为0型电液换向阀。
6)作多机能四通阀
连接换向阀，利用对电磁换向阀的控制实现多机能功能。
2、插装压力控制阀
对插装阀的x腔进行压力控制，便可构成压力控制阀。
1)作溢流阀或顺序阀
在压力型插装阀芯的控制盖板上连接先导调压阀(溢流阀) ,当出油口接油箱，此阀起溢流阀作用;当出油口接另一工作油路，则为顺序阀。
2)作卸荷阀
连接二位二通换向阀，当电磁铁通电时，出口接油箱，则构成卸荷阀。
3)作减压阀
采用插装阀芯和溢流阀连接，则构成减压阀。液压油P从1流入P2流出，出口油液通过阀芯上的中心阻尼孔、盖板和先导阀接通。当减压阀出口的压力较小，不足以顶开先导阀芯时，主阀芯上的阻尼孔只起通油作用，使主阀芯上、下两腔的液压力相等，而上腔又有一个小弹簧作用，必使主阀芯处在F端极限位置，减压阀芯大开，不起减压作用; 当压力增大到先导阀的开启压力时，先导阀打开，泄漏油液单独流回油箱，实行外泄。减压阀在调定压力下正常工作时，由于出口压力与先导 阀溢流压力和主阀芯弹簧力的平衡作用，维持节流降压口为某定值。当出口压力增大，由于阻尼孔液流阻力的作用产生压力降，主阀芯所受的力不平衡，使阀芯上移，减小节流降压口，使节流降压作用增强;反之，出口的压力减小时，阀芯下移，增大节流降压口，使节流降压作用减弱，控制出口的压力维持在调定值。
3、插装流量控制阀
插装流量阀同样有节流阀和调速阀等型式。
1)作节流阀
在方向控制插装阀的盖板上安装阀芯行程调节器，调节阀芯和阀体间节流口的开度便可控制阀口的通流面积，起节流阀的作用，如图12a。实际应用时，起节流阀作用的插装阀芯一般采用滑阀结构，并在阀芯上开节流沟槽。
2)作调速阀
插装式节流阀同样具有随负载变化流量不稳定的问题。如果采取措施保证节流阀的进、出口压力差恒定，则可实现调速阀功能。如图12b连接的减压阀和节流阀就起到这样的作用。

液压机是对金属材料塑料、橡胶和粉末冶金制品进行压力加工的设备，在工业部门得到了广泛应用,如金属材料的拉伸、冲裁弯曲翻边冷挤压以及成型加工等，还用于校正、压装、粉末冶金制品和磨料制品的压制成型及塑料制品、绝缘材料的压制成型等。为完成上述工作,液压机应能产生较大的压力,因此,液压系统工作压力、尺寸和流量也大,对其设计要求也高,是较典型的高压大流量系统。①液压系统压力应能经常变换和调节,并能产生较大压力，以满足不同的工作要求。②空程速度大、加压时推力大,系统功率大,要求功率利用率高。③空程与压制时,其速度与压力相差甚大,所以多采用高低压泵组或恒功率变量泵供油系统.以满足低压快速行程和高压慢速行程要求。