详细解读工控行业三大常用执行器

Detailed interpretation of the industrial control industry three common actuators

中英合资天蝶阀门带大家来认识一下，工控行业中，三款常用的执行器。并详细解读他们之间有何不同。今后我们在工业控制系统中，该如何选择执行器，便会一目了然。

In the industrial control industry, the three most commonly used actuator.And explain in detail how they differ.
In the future, it will be clear how to select the actuator in the industrial control system.

执行器是接受调节器输出信号对调节对象施加作用的装置。通常用在驱动阀门等机械设备中。根据执行器使用的控制介质不同，可以分为：气动、液动和电动执行器三种。按输出位移的形式，执行器有转角型和直线型两种。按动作规律，执行器可分为开关型、积分型和比例型三类。按输入控制型号，执行器分为可以输入空气压力信号、直流电流信号、电接点通断信号、脉冲信号等几类。
The actuator is the device that accepts the output signal of the regulator to adjust the object.It is usually used in driving valves and other mechanical equipment.According to the different control medium used by actuators, it can be divided into three kinds: pneumatic, electric and hydraulic actuators.According to the form of output displacement, there are two types of actuators: rotary and linear.According to the law of motion, actuators can be divided into switch type, integral type and proportional type.According to the input control model, the actuator is divided into input air pressure signal, DC current signal, electrical contact on-off signal, pulse signal and other types.

三种执行器的优缺点
The advantages and disadvantages of the three actuators

1.液动执行器
1.Hydraulic actuator

液动执行器是以液压油为动力源来完成预定运动要求和实现各种机构功能的机构。
Hydraulic actuator is a mechanism that uses hydraulic oil as a power source to fulfill predetermined motion requirements and realize various functions of institutions.

优点：
The advantages:
（1）在输出同等功率的条件下，机构结构紧凑，体积小、重量轻、惯性小。
 (1) under the condition of equal output power, the mechanism has compact structure, small volume, light weight and small inertia.
（2）工作平稳，冲击、振动和噪音都较小，易于实现频繁的启动、换向，能够完成旋转运动和各种往复运动。
(2) The work is stable, the impact, vibration and noise are small, and it is easy to realize frequent start-up and reversal, and it can complete rotary motion and various reciprocating motions.
（3）操纵简单、调速方便，并能在大的范围内实现无级调速，调速比可达5000。
(3) The operation is simple, the speed is convenient, and stepless speed regulation can be realized in a large range, and the speed ratio can reach 5000.
（4）可实现低速大力矩传动，无需减速装置。
(4) It can realize low-speed and high-moment transmission without deceleration device.
缺点：
The disadvantages:
（1）油液的粘性受温度变化的影响大，不宜用于低温和高温环境中。
 (1) The viscosity of oil is greatly affected by temperature changes and should not be used in low temperature and high temperature environments.
（2）液压组件的加工和配合要求精度高，加工工艺困难，成本高。
(2) The hydraulic components require high precision in processing and fitting, and the processing technology is difficult and the cost is high.

2.气动执行器
2.Pneumatic actuator

优点：
The advantages:
(1)以空气为工作介质，工作介质获得比较容易，用后的空气排到大气中，处理方便，与液压传动相比不必设置回收的油箱和管道。
(1)Using air as the working medium, the working medium is relatively easy to obtain, the used air is discharged into the atmosphere, and the handling is convenient. Compared with the hydraulic transmission, it is not necessary to set the recovered oil tank and pipeline.
(2)因空气的粘度很小（约为液压油动力粘度的万分之一），其损失也很小，所以便于集中供气、远距离输送。外泄漏不会像液压传动那样严重污染环境。
(2)Because the viscosity of the air is very small (about 1/10000 of the dynamic viscosity of the hydraulic oil), its loss is also very small, so it is convenient for centralized gas supply and long-distance transportation. Leakage will not seriously pollute the environment like hydraulic transmission.
(3)与液压传动相比，气压传动动作迅速、反应快、维护简单、工作介质清洁，不存在介质变质等问题。
(3)Compared with the hydraulic transmission, the pneumatic transmission has the advantages of rapid action, quick response, simple maintenance, clean working media, and no deterioration of medium.
(4)工作环境适应性好，特别在易燃、易爆、多尘埃、强磁、辐射、振动等恶劣工作环境中，比液压、电子、电气控制优越。
(4)The adaptability of the working environment is good, especially in the bad working environment, such as flammable, explosive, multi dust, strong magnetic, radiation, vibration and so on, which is superior to the control of hydraulic, electronic and electrical control.
(5)成本低，过载能自动保护。
(5)The cost is low and the overload can be automatically protected.
缺点：
The disadvantages:
(1)由于空气具有可压缩性，因此工作速度稳定性稍差。但采用气液联动装置会得到较满意的效果。
(1)Because of the compressibility of the air, the working speed is slightly worse. But the use of gas-liquid linkage will get satisfactory results.
(2)因工作压力低（一般为0.31.0MPa），又因结构尺寸不宜过大，总输出力不宜大于10～40kN。
(2)Due to low working pressure (generally 0.31.0MPa), and the size of the structure should not be too large, the total output power should not be greater than 10 ~ 40kN.
(3)噪声较大，在高速排气时要加消声器。
(3)The noise is large, and mufflers should be added at high speed.
(4)气动装置中的气信号传递速度在声速以内比电子及光速慢，因此，气动控制系统不宜用于元件级数过多的复杂回路。
(4)The gas signal transmission speed in the pneumatic device is slower than the speed of electrons and light within the speed of sound. Therefore, the pneumatic control system should not be used in the complex circuit with too much element series.

3.电动执行器
3.Electric actuator

优点：
The advantages:
(1)取用能源方便容易、传输信号速度快、信号传输距离远、以便于集中操作控制。
(1)Energy consumption is easy and convenient, and the speed of signal transmission is fast, and the distance of signal transmission is far away, so as to facilitate centralized operation and control.
(2)度、灵敏度相对较高，与其他电动调节仪表配合方便易操作，接线安装简单。
(2)The accuracy and sensitivity are relatively high. It is convenient and easy to operate with other electric regulating instruments, and the wiring and installation are simple.
(3)使用效果证明，电动执行器抗偏离能力很好，所输出的力矩或推力基本恒定，能做到很好的克服介质的不平衡力，确保达到相关工艺参数的控制，因此该产品控制精度相比气动执行器要稍高一些。
(3)The use effect proves that the electric actuator has a good anti deviation ability and the output torque or thrust is basically constant. It can overcome the imbalance force of the medium well and ensure the precise control of the related process parameters. Therefore, the control precision of the product is slightly higher than the pneumatic actuator.
(4)若配备伺服放大器，能够轻易实现正、反作用的互换，亦可轻松设定信号阀位状态，如在出现故障时，一定是停留在原位，这种能力是气动执行器产品所无法达到的，因为气动执行器须借助于配备组合保护系统来实现保位功能。
(4)If equipped with a servo amplifier, it can easily achieve positive and reverse interchangeability, and it can also easily set the state of signal valve position, If a fault occurs,, it must stay in situ, this ability is not achieved by the pneumatic actuator products, because the pneumatic actuator is required to be equipped with a combination protection system to protect the position. Function.
缺点：
The disadvantages:
(1)仅适用于防爆要求不高，气源缺乏的场所。结构相对复杂，推力小，平均故障率比气动执行机构较高，而由于结构复杂性的问题，对于现场维护人员的技术要求也相对较高。
(1)It is only applicable to places where explosion-proof is not high and gas sources are scarce.the structure is relatively complex, the thrust is small, the average fault rate is higher than the pneumatic actuator, and the technical requirements of the field maintenance personnel are relatively high due to the complexity of the structure.
(2)电机运行会产生热量，调节频率大的话，易造成电机过热，也增加了减速齿轮的磨损。
(2)The motor will generate heat when running. If the adjustment frequency is large, it will cause overheating of the motor and increase the wear of the reduction gear.
(3)还有运行较慢，从调节器输出信号开始，到调节阀响应而运动至位置，往往耗时较多，以上是较之气动或液动执行器所表现不足的地方。
(3)The operation is slow, from the output signal of the regulator to the response of the regulator to the specified position, which is often more time-consuming, and the above is a place where the pneumatic or hydraulic actuator is insufficient.

三种执行器的对比

Comparison of executive agencies

①气动执行器
①pneumatic actuator
执行器和调节机构是统一的整体，执行器有薄膜式和活塞式两类。活塞式行程长，适用于要求有较大推力的场合；而薄膜式行程较小，只能直接带动阀杆。由于气动执行器有结构简单，输出推力大，动作平稳可靠，并且安全防爆等优点，在化工，炼油等对安全要求较高的生产过程中有广泛的应用。
 Actuators and regulators are a unified entity. Actuators have two types: diaphragm and piston.The piston stroke is long and is suitable for applications where there is a need for high thrust; while the film-type stroke is small and can only directly actuate the valve stem.Because the pneumatic actuator has the advantages of simple structure, large output thrust, stable and reliable operation, safety and explosion proof, etc., it is widely used in the chemical industry, oil refining and other high-security production processes.
②液动执行器
②Hydraulic actuator
推力大，现在一般都是机电一体化的，但比较笨重，所以现在很少使用，比如三峡的船阀用的就是液动执行器。
Thrust is the largest, but now it is generally electromechanical integration, but it is cumbersome, so it is rarely used now, for example, the Three Gorges ship valve uses hydraulic actuator.
③电动执行器
③Electric actuator
安全防爆性能差，电机动作不够迅速，且在行程受阻或阀杆被扎住时电机容易受损。尽管近年来电动执行器在不断改进并有扩大应用的趋势，但从总体上看不及气动执行器应用得普遍。
The safety and explosion-proof performance is poor, the motor is not fast enough, and the motor is easily damaged when the stroke is blocked or the stem is tied.Although electric actuators have been continuously improved in recent years and there is a tendency to expand applications,they are generally not as widely applied as pneumatic actuators.

执行器的选择
Choice of executive agencies

主要考虑因素
Main considerations

①可靠性；

① reliability;
②经济性；

② economy;

③动作平稳、足够的输出力；

③ a stable and sufficient output force;

④重量外观；

④ the appearance and weight;

⑤结构简单、维护方便。

⑤The simple structure and the convenient maintenance  

电动执行器与气动执行器的选择比较
Selection and comparison of electric actuator and pneumatic actuator
 (1)气动执行器简单可靠
 (1)The pneumatic actuator is simple and reliable
老式电动执行器可靠性差是它过去的一贯弱点，然而在90年代电子式执行器的发展*解决了这一问题，可以在5~10年内免维修，它的可靠性甚至超过了气动执行器。正由于此，笔者认为，它将成为下世纪调节阀的主流。
The poor reliability of the old electric actuator is the weakness in the past. However, in 90s, the development of the electronic actuator completely solved the problem, and it could be avoided in 5~10 years, and its reliability was even more than the pneumatic actuator. Because of this, I believe that it will become the mainstream of regulatory valve in the next century.
 (2)驱动源
 (2)Drive source
气动执行器的大不足就是需别设置气源站，增加了费用；电动阀的驱动源随地可取。
The biggest deficiency of pneumatic actuators is is to set up gas source station and increase the cost; the driving source of electric valves is desirable everywhere.
(3)价格方面
(3)Price
气动执行器必须附加阀门定位器，再加上气源，其费用与电动阀不相上下（进口电气阀门定位器与进口电子式执行器价格相当；国产定位器与国产电动执行器不相上下）。
Pneumatic actuators must be equipped with a valve positioner and plus gas source, the cost of which is comparable with that of the electric valve (imported electric valve positioner is equivalent to imported electronic actuator; domestic positioner is comparable to domestic electric actuator) .
 (4)推力和刚度两者相当。
 (4)Both thrust and stiffness are comparable.
 (5) 防火防爆
 (5)Fire and explosion protection
气动执行器+电气阀门定位器”略好于电动执行器。
“Actuator + Electric Valve Positioner" is slightly better than the electric actuator.

推荐意见
Suggestions
 (1) 在可能的情况下，建议选用进口电子式执行器配国产阀（如全功能超轻型阀）以用于国产化场合、新建项目等。
 (1) in the case of possible, it is suggested that imported electronic actuators should be selected with domestic valves (such as full function ultra light valves) for domestic applications and new projects.
(2)薄膜执行器虽存在推力不够、刚度小、尺寸大的缺陷，但其结构简单，所以，目前仍是使用多的执行器。但这里我们强调的是应该选用ZHA、ZHB型的精小型薄膜执行器去代替ZMA、ZMB型的老式薄膜执行器，以获得更轻的重量、更小的尺寸和大的输出力。
(2)Thin film actuator has the defects of insufficient thrust, small stiffness and large size, but its structure is simple, so it is still the most used actuator at present.But we emphasize that it is best to use ZNA, ZHB fine small-film actuators instead of ZMA, ZMB type of old film actuators to get lighter weight, smaller size and large output force.
 (3)活塞执行器选择注意方面：
 (3)Piston actuator selection Note:
①气动薄膜执行器推力不够时，选用活塞执行器来提高输出力；对大压差的调节阀（如中压蒸汽切断），当DN≥200时，甚至要选双层活塞执行器；
 ① When the thrust of the pneumatic diaphragm actuator is not enough, the piston actuator is used to increase the output force; for large pressure differential regulators (such as medium pressure steam cutoff), when the DN ≥ 200, even the double piston actuator must be selected;
②对普通调节阀，还可选用活塞执行器去代替薄膜执行器，使执行器的尺寸大大减小，就此观点而言，气动活塞调节阀使用会更多；
②For ordinary regulating valves, the piston actuator can be used to replace the film actuators, so that the size of the actuator is greatly reduced. In this view, the pneumatic piston regulating valve will be used more.
③对角行程类调节阀，其角行程执行器，典型的结构是双活塞齿轮齿条转动式。
③ For diagonal-type control valves, the angular-stroke actuator is typically a dual-piston rack-and-pinion type.