原文：
            随着我国工业的迅速发展，电动调节阀在冶金、石油化工等领域的应用越来越广泛，其稳定性、可靠性也显得越来越重要，它的工作状态的好坏将直接影响自动控制过程，本文将详细阐述电动调节阀的使用和维修。 1.安装使用注意事项 新设计、安装的控制系统，为了确保调节阀在开车时能正常工作，并使系统安全运行，新阀在安装之前，应首先检查阀上的铭牌标记是否与设计要求相符。同时还应对以下项目进行调试。 基本误差限；全行程偏差；回差；死区；泄漏量(在要求严格的场合时进行)。 如果是对原系统中调节阀进行了大修，除了对上述各项进行校验外，还应对旧阀的填料函和连接处等部位进行密封性检查。 调节阀在现场使用中，很多往往不是因为调节阀本身质量所引起，而是对调节阀的安装使用不当所造成，如安装环境、安装位置及方向不当或者是管路不清洁等原因所致。

     因此电动调节阀在安装使用时要注意以下几方面：

 (1)调节阀属于现场仪表，要求环境温度应在－25～60℃范围，相对湿度≤95%。如果是安装在露天或高温场合，应采取防水、降温措施。在有震源的地方要远离振源或增加防振措施。

 (2)调节阀一般应垂直安装，特殊情况下可以倾斜，如倾斜角度很大或者阀本身自重太大时对阀应增加支承件保护。

 (3)安装调节阀的管道一般不要离地面或地板太高，在管道高度大于2m时应尽量设置平台，以利于操作手轮和便于进行维修。

 (4)调节阀安装前应对管路进行清洗，排除污物和焊渣。安装后，为保证不使杂质残留在阀体内，还应再次对阀门进行清洗，即通入介质时应使所有阀门开启，以免杂质卡住。在使用手轮机构后，应恢复到原来的空档位置。

(5)为了使调节阀在发生故障或维修的情况下使生产过程能继续进行，调节阀应加旁通管路。 同时还应特别注意，调节阀的安装位置是否符合工艺过程的要求。

 (6)电动调节阀的电气部分安装应根据有关电气设备施工要求进行。如是隔爆型产品应按《爆炸危险场所电气设备安装规范》要求进行安装。如现场导线采用SBH型或其它六芯或八芯、外径为Φ11.3mm左右的胶皮安装电缆线。在使用维修中，在易爆场所严禁通电开盖维修和对隔爆面进行撬打。同时在拆装中不要磕伤或划伤隔爆面，检修后要还原成原来的隔爆要求状态。

 (7)执行机构的减速器拆修后应注意加油润滑，低速电机一般不要拆洗加油。装配后还应检查阀位与阀位开度指示是否相符。 2.常见故障部位及原因分析 调节阀工作性能的好坏会直接影响整个调节系统的工作质量。由于调节阀在现场是与被调介质直接接触的，工作环境十分恶劣，因此容易产生各种故障。在生产过程中，除了随时排除这些故障外，还必须进行经常性的维护和定期检修。尤其是对使用环境特别恶劣的调节阀，更应重视维护和定期检修。 不同形式的调节阀，其故障及其产生原因是不一样的。

       现以四川仪表总厂生产的直行程电动调节阀为例，说明电动调节阀的一般故障及检修方法。 2.1伺服放大器 伺服放大器正常工作状态时：

 (1)无输入信号时，不应有输出电压。 (2)开环死区电流≤160μA(Ⅱ型为100μA)。

 (3)输入信号＞240μA(Ⅱ型为150μA)时，输出负载电压为205～220VAC。 (4)输出电压基本对称。 若伺服放大器工作不正常，则各部分可能有以下几种情况： (1)前置磁放大器 ①无信号输入时，双拍磁放大器输出通过电位器W101可调至零。不能调零则可能是： A、变压器W101脱焊或损坏。 B、电阻R110、R111和电解电容C101、C102虚焊或脱焊。 C、二极管D105～D108虚焊或损坏。 D、偏移电流不正常。 E、交流绕组不对称。 ②有输入信号，但无输出或输出不对称可能是： A、变压器B301供交流绕组电流的次级端电压不对称。 B、电阻R110和R111的阻值有变化，电解电容C110、C111损坏。 C、交流激磁绕组短路。 D、二极管D105～D108中有个别管损坏或虚焊。

(2)触发器有输入时，其中一侧触发器在示波器屏幕上应有脉冲信号，改变输入信号极性，则另一侧触发器有脉冲信号。两组触发脉冲个数和幅值应基本相同。否则有以下几种情况。 ①无输入信号(前置磁放大器在正常工作状态下)，电磁阀输出端有触发脉冲，可能是： A、有触发脉冲输出一侧的三极管损坏，或者是c、e极虚焊。 B、电阻R204、R205、R208、R209阻值有变化。 ②有输入信号，输出端无触发脉冲，可能是： A、无输出脉冲一侧的三极管、单结管损坏。 B、无输出脉冲一侧的脉冲变压器初级或次级断路或短路。 C、无输出脉冲一侧的二极管(D207或D208)短路。 ③输出触发脉冲不正常有以下几种现象： A、无信号时两组触发器有脉冲输出，疏水阀加信号后又都正常，可能是电解电容C202或C203虚焊。 B、开始触发器两侧输出都正常，工作一段时间后，输出脉冲逐渐消失，可能单结管有问题。 C、输出出现正、负脉冲，可能是二极管D207、D208被击穿或虚焊。

 (3)经过上述检查和维修，在控制回路无故障情况下伺服放大器应能正常工作。否则有以下两种情况： ①无输入信号时，有输出电压(电压接近220VAC)则可能是： A、可控硅SCR1、SCR2损坏。 B、电容C301、C302被击穿。 ②有输入信号时，无输出信号或输出电压偏低，则可能是： A、二极管D301～D308中有被击穿的。 B、可控硅SCR1、SCR2损坏。 2.2调节阀 当输入4～20mA信号时，调节阀阀杆能在额定行程内随信号变化而上、下移动自如。

   如不能正常动作，可能有以下故障： ①操作手轮感觉异常 A、感觉太轻，可能是手轮卡销脱落或断裂。 B、感觉太重或旋不动。衬里阀门减速器内有异物卡塞；阀芯与衬套或与阀座卡死；阀杆严重弯曲。 ②输入4～20mA信号，调节阀不动作。 A、系统接线有误。 B、电机分相电容CD损坏。 C、电机接线开路。 D、阀芯脱落或阀杆断裂(此时执行机构有动作) ③输入4～20mA信号，调节阀走不完额定行程。 A、差动变压器位置未调好。 B、二极管D701～D712中有个别损坏。 C、三极管BG701损坏。

    (4)现场使用时的其它故障。 ①阀震荡、鸣叫。 A、灵敏度调得太高，电动执行器执行机构产生振荡。 B、流体压力变化太大，执行机构推力不足。 C、调节阀选择大了、阀常在小开度工作。 D、介质流动方向与阀门关闭方向一致。 E、附近其它震源影响，支撑不稳。 F、阀芯和衬套磨损严重。 ②阀动作迟钝。 A、介质粘性太大，有堵塞或结焦现象。 B、填料老化，填料压得太紧。 ③泄漏量大。 A、阀芯或阀座被腐蚀、磨损。 B、阀座松动或螺纹被腐蚀。 C、阀座、特殊阀门阀芯上有异物。 D、阀的始点(电开式)或终点(电闭式)未调好。 ④填料及上、下阀盖连接处渗漏。 A、填料压盖没压紧。 B、聚四氟乙烯填料老化变质。 C、阀杆损坏。 D、紧固螺母松动。 E、密封垫损坏。 3.结束语 电动调节阀的正确使用和维修，不仅能提高过程控制的可靠性，也能增加电动调节阀的使用寿命，对企业的节能降耗有着可观的经济效益。

“ Electric control valve maintenance and use of ”是由中国调节阀网提供的国际阀门新闻，译文仅供参考。另外，中国调节阀网还提供相关产品搜索： CV3000调节阀、 电动调节阀、 气动调节阀、 手动调节阀、 核用调节阀等。

译文：
         With the rapid development of China's industry, the electric control valve in metallurgy, petroleum chemical and other fields of applied more widely, its stability, reliability becomes more and more important, its work directly affects the state of Zidongkongzhi process, this article will detail the use of electric control valves and maintenance. 1. Installation Notes New design, installation of control systems, in order to ensure that the valves work properly in the car and make the system safe operation, before installing the new valve should first check whether the valve on the nameplate labeled consistent with the design requirements. The following items should also debug. Basic error limit; full strokeBall Valves deviation; hysteresis; dead; leakage (in the strict occasions when). If the original system had valve repair, in addition to the above are verified, but also deal with old valve stuffing and sealing joints and other parts for inspection. Regulating valve in the field use, many are not because of the valve mass is caused Er Shi An Zhuang control valve using improper response, such as installation Huan Jing, installation location, and Fang Xiang improper Huozhe is dirty and so Yuanyinsuozhi pipeline. Therefore, electric control valve in the installation should pay attention to the following: (1) regulating valves are field instruments, the Environment and temperature should be in the range of -25 ~ 60 ℃, relative humidity ≤ 95%. If it is installed in the open air or in high temperature, should take water, cooling measures. In a place away from the source of the vibration source or increase the anti-vibration measures. (2) regulating valve should normally be installed vertically, special circumstances can be tilted, such as the tilt angle is large or valve itself is too large weight bearing parts of the valve protection should be increased. (3) installation of the pipeline control valve generally not too high off the ground or floor, the pipe height is larger than 2m to set platform should be as much as possible, to facilitate the manipulator wheel and easy maintenance. (4) pipe valve should be cleaned before installation to remove dirt and weld slag. After installation, to ensure not to impurities left in the valve body, the valve should be cleaned again, that pass into the media so that all valves should be open, to avoid impurities stuck. After using the hand wheel body, should be restored to its original neutral position. (5) In order to control valve in the event of failure or maintenance circumstances make the production process to continue, bypass pipe valve should be added. Should also pay particular attention to valve installation location is consistent with the requirements process. (6) electric control valve installed on the electrical part of the construction in accordance with the requirements relating to electrical equipment. The case of flameproof products should be "explosion hazardous area electrical installation standard" requirements for installation. Such as live wires and other six with SBH-type core or 8 core, outer diameter of about rubber Φ11.3mm installed cable. In the use and maintenance, in place non-explosive power of the explosion of maintenance and opening the lid to pry playing surface. Do not knock the same time dismantling the explosion injured or scratched surface, after overhaul to restore the original state of explosion-proof requirements. (7) The executive body of the reducer overhaul should be noted that after lubrication, low-speed motor fuel generally not washable. Assembly should also check the valve position after position with the valve opening direction is consistent. 2. Common causes of failure location and Valve job performance will directly affect the quality of the work-conditioning systems. As the valve is to be transferred at the scene in direct contact medium, the work environment is very poor, so they are prone to failure. In the production process, in addition to any removal of these failures, it must also carry out regular maintenance and periodic overhaul. In particular, the use of environment, especially the poor control valve, more attention should be paid to maintain and regularly repair. Different forms of control valve, its failure and its causes is not the same. Sichuan Instrument Factory production is the direct travel electric control valve to illustrate the general electric control valve failure and repair methods. 2.1 Servo Amplifiers Servo amplifier working status: (1) No input signal, there should be no output voltage. (2) open-loop dead current ≤ 160μA (Ⅱ type is 100μA). (3) the input signal> 240μA (Ⅱ type is 150μA), the output load voltage of  205 ~ 220V  AC. (4) the output voltage fundamental symmetry. If the servo amplifier is not working properly, then there may be various parts of the following situations: (1) pre-magnetic amplifier ① no signal input, two-shot magnetic amplifier output adjustable via potentiometer W101 to zero. Can not zero it could be: A, transformer W101 loose weld or damaged. B, resistors R110, R111, and electrolytic capacitors C101, C102 Weld or loose soldering. C, diode D105 ~ D108 Weld or damaged. D, offset current is not normal. E, AC winding asymmetry. ② The input signal, but no output or output asymmetry may be: A, B301 for the exchange of winding current transformer secondary voltage asymmetry. B, resistors R110 and R111 of the resistance has changed, electrolytic capacitors C110, C111 damage. C, AC excitation winding short circuit. D, diode D105 ~ D108 in the individual tube is damaged or Weld. (2) flip-flop with input, of which side of the screen on the oscilloscope should trigger pulse signal, change the input signal polarity, the other side of the trigger pulse signals are. Trigger pulse number and amplitude of the two groups should be basically the same. Otherwise, the following situations. ① no input signal (front magnetic amplifier in the normal state), output a trigger pulse, may be: A, a trigger pulse output side of the transistor is damaged, or c, e very Weld. B, resistors R204, R205, R208, R209 resistance has changed. ② The input signal, no output trigger pulse, may be: A, no output pulse at the side of the transistor, unijunction damage. B, no output pulse at the side of the pulse transformer primary or secondary circuit or short circuit. C, no output pulse at the side of the diode (D207 or D208) short circuit. ③ output trigger pulse is not normal and the following phenomena: A, no signal triggers a pulse output when the two groups, add signals then are normal, may be the electrolytic capacitor C202 or C203 Weld. B, both sides began to flip-flop outputs are normal, working for some time, the output pulse gradually disappeared, may have problems unijunction. C, the output shows positive, negative pulse, may be the diode D207, D208 breakdown or Weld. (3) After the above inspection and maintenance, trouble-free in the case of control loop servo amplifier should be able to work properly. Otherwise, the following two situations: ① no input signal, there is Gate Valvesthe output voltage (voltage close to 220VAC) may be: A, thyristor SCR1, SCR2 damage. B, capacitor C301, C302 is the breakdown. ② The input signal, no output signal or output voltage is low, it could be: A, diode D301 ~ D308 has been breakdown. B, thyristor SCR1, SCR2 damage. 2.2 Control Valve 4 ~ 20mA input signal, the control valve stem can be rated with the signal changes within the travel, the next move freely. If you can not operate normally, may have the following breakdown: ① manipulators round paresthesia A, felt too light, round card sales may be hand-off or broken. B, feeling too heavy or Check Valvesspin fixed. There are foreign Case reducer; spool and bushing or stuck with the valve seat; stem severe bending. ② 4 ~ 20mA input signal, adjusting valve does not work. A, the system wiring is incorrect. B, split-phase capacitor motor damaged CD. C, open electrical wiring. D, spool or stem broken off (the executing agency to take any action at this time) ③ 4 ~ 20mA input signal, control valve to go finish the rated travel. A, differential transformer position is not adjusted well. B, diode D701 ~ D712 in individual damage. C, transistor BG701 damage. (4) on-site use of other failures. ① valve shocks, tweet. A, sensitivity adjusted too high actuator oscillation. B, too much fluid pressure changes, implementing agencies lack of thrust. C, control valve selection big, valves often work in a small opening. D, medium flow direction and Butterfly Valvesthe valve closed in the same direction. E, near the other focal effects of propping. F, spool and bushing wear serious. ② valve is slow. A, medium viscosity too, have blocked or coking phenomenon. B, packing aging, the weight of packing too tight. ③ large leak. A, spool or the valve seat is corrosion, wear and tear. B, seat loose or corroded threads. C, valve seats, valve on a foreign body. D, the valve starting point Globe Valves(open call) or end (call closed) did not adjust well. ④ filler and the upper and lower junction leakage valve cover. A, no compression packing gland. B, PTFE packing aging deterioration. C, stem damage. D, tighten the nut loose. E, damage gaskets. 3. Conclusion Electric control valve of the proper use and maintenance, not only can improve the reliability of process control can also increase the service life of electric control valve, on the company's energy consumption has a considerable economic benefits.

原文来源：http://www.1tiaojiefa.com/

2010-08-23 08:40

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