原文：
         调节阀所用执行器不外乎气动、电动、液动(电液动)这三种，其使用性能各有优劣，下面分述之。

 　　1、调节阀气动执行机构：现今大多数工控场合所用执行器都是气动执行机构，因为用气源做动力，相较之下，比电动和液动要经济实惠，且结构简单，易于掌握和维护。由维护观点来看，气动执行机构比其它类型的执行机构易于操作和校定，在现场也可以很容易实现正反左右的互换。它最大的优点是安全，当使用定位器时，衬氟阀门对于易燃易爆环境是理想的，而电讯号如果不是防爆的或本质安全的则有潜在的因打火而引发火灾的危险。所以，虽然现在电动调节阀应用范围越来越广，但是在化工领域，气动调节阀还是占据着绝对的优势。

　　2、调节阀电动执行机构：波纹管阀门电动执行机构主要应用于动力厂或核动力厂，因为在高压水系统需要一个平滑、稳定和缓慢的过程。电动执行机构的主要优点就是高度的稳定和用户可应用的恒定的推力，最大执行器产生的推力可高达225000kgf，能达到这么大推力的只有液动执行器转子泵，隔膜阀但液动调节阀造价要比电动调节阀高很多。电动调节阀的抗偏离能力是很好的，输出的推力或力矩基本上是恒定的，可以很好的克服介质的不平衡力，达到对工艺参数的准确控制，所以控制精度比气动调节阀要高。如果配用伺服放大器，可以很容易地实现正反作用的互换，也可以轻松设定断信号阀位状态(保持/全开/全关)，而故障时，一定停留在原位，这是气动调节阀所作不到，气动调节阀必须借助于一套组合保护系统来实现保位。

　　电动调节阀执行机构的缺点主要有：结构较复杂，锻钢阀门 更容易发生故障，且由于它的复杂性，对现场维护人员的技术要求就相对要高一些；电机运行要产生热，如果调节太频繁，容易造成电机过热，产生热保护，同时也会加大对减速齿轮的磨损；另外就是运行较慢，从调节阀调节器输出一个信号，到调节阀响应而运动到那个相应的位置，需要较长的时间，这是它不如气动、液动执行器的地方。

 　　3、调节阀液动执行机构：当需要异常的抗偏离能力和高的推力以及快的形成速度时，我们往往选用液动或电液执行机构。因为液体的不可压缩性，采用液动执行器的优点就是较优的抗偏离能力，这对于调节阀调节工况是很重要的，铜阀门因为当调节元件接近阀座时节流工况是不稳定的，越是压差大，这种情况越厉害。另外，调节阀液动执行机构运行起来非常平稳，响应快，所以能实现高精度的控制。电液动执行机构是将电机、油泵、电液伺服阀集成于一体，只要接入电源和控制信号即可工作，而液动执行器和气缸相近，只是比气缸能耐更高的压力，它的工作需要外部的液压系统，工厂中需要配备液压站和输油管路，相比之下，还是电液执行器更方便一些。

　　调节阀液动执行机构的主要缺点就是造价昂贵，体检庞大笨重，特别复杂和需要专门工程，所以大多数都用在一些诸如电厂、石化等比较特殊的场合。

“ Knowledge of control valve actuators Introduction ”是由中国安全阀网提供的国际阀门新闻，译文仅供参考。另外，中国安全阀网还提供相关产品搜索： 封闭式安全阀、 高压安全阀、 锅炉安全阀、 蒸汽安全阀、 主安全阀(主阀)等。

译文：
           Regulating valve used nothing more than pneumatic actuators, electric, hydraulic (hydraulic power) of these three, the use of performance advantages and disadvantages, the following describe these. 1, control valve pneumatic actuator: now the majority of industrial control actuators are used in situations pneumatic actuator, because the gas source as power, contrast, electrical and hydraulic than to cost, simple structure, easy to master and maintenance. From the maintenance point of view, pneumatic actuator than other types of implementing agencies is easy to operate and calibrate, in the field can also be very easy to implement positive and negative about the exchange. It is the biggest advantages of security, when using the positioning device when, forBellow Seal Valve flammable and explosive environment is ideal, while the telecommunications number or nature, if not proof of safety whilst Qianzai the result of ignition and fire hazard. So, while the electric valve increasingly wide range of applications, but in the chemical industry, pneumatic control valve or occupy an absolute advantage. 2, control valve actuators: electric actuators are mainly used in power plants or nuclear power plants, because high-pressure water system needs a smooth, steady and slow process. The main Needle Valvesadvantage of electric actuators is the high degree of stability and the user can apply a constant thrust, maximum thrust generated by the actuator up to 225000kgf, can achieve only so much thrust rotor hydraulic actuator pump, but the cost of hydraulic control valve to much higher than the electric control valve. Electric control valveForged Steel Valves is a very good resistance to deviate from the ability of the output of the thrust or torque is basically constant, can be a good medium to overcome the imbalance in power, to achieve the precise control of the process parameters, the pneumatic valve control accuracy than to high. If equipped with a servo amplifier, can easily achieve positive and negative effects of the exchange, you can easily set off the signal valve position status (hold / Full On / Off), and failure, must remain in situ, which is air conditioning Valve's not, pneumatic control valve must be combined by means of a protection Water Pump Control Valves system to achieve security bit. Electric valve actuator shortcomings are: the structure more complex and more prone to failure, and because of its complexity, on-site maintenance personnel of the technical requirements on the relatively higher; motor run to generate heat, if the regulation is too frequent likely to cause motor overheating, resulting in thermal protection, but alsoFilter increase the wear reduction gear; other is running slow, the output from the regulator valve a signal to the control valve response to the movement to the appropriate location that requires a longer time, this is it not as good as pneumatic, hydraulic actuator place. 3, control valve hydraulic actuator: When you need exceptional ability and high resistance to deviate from the rapid formation of thrust and speed, we tend to use hydraulic or electro-hydraulic actuator. Because the liquid can not be compressed, using the advantages of hydraulic actuators is the better resistance of the deviation from capacity, condition for the valve adjustment is very important because when the regulatory element close to the seat when the cutting condition is unstable, Water Power Control ValvesThe more pressure large, the more severe situation. In addition, the control valve hydraulic actuator up and running very smooth, quick response, they are able to achieve high-precision control. Electric hydraulic actuator is the motor, pump, servo valve integrated in one, as long as you can access the power and control signals, while the hydraulic actuators and cylinders are similar, but higher than the cylinder pressure capability, it requires an external hydraulic system with hydraulic power plant needs and pipeline, compared to, or electro-hydraulic actuator is more convenient. Hydraulic valve actuator is the major shortcomings of expensive, bulky physical examination, particularly complex and require specialized engineering, so most are used in some, such as power plants, petrochemical, and other more special occasions.

原文来源：http://www.1anquanfa.com/

2010-07-26 07:57

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