Pneumatic Actuators

Pneumatic Actuators

1 Introduction

Pneumatic actuators are devices in which energy of compressed air is utilized for carrying out mechanical work like linear, rotary, and oscillatory movement. The most commonly applied actuator is the pneumatically driven actuator, because the power source-compressed air-is relatively inexpensive compared to electrical or hydraulic power sources. For that reason, approximately 90 percent of all actuators in service today are driven by compressed air. When compared to the cost of electromechanical and electrohydraulic actuators, pneumatic actuators are relatively inexpensive as well as easy to understand and maintain. Most are available as standard off-the-shelf products in a number of predetermined sizes corresponding to maximum thrust. Only in special services are special-engineered actuators produced, such as applications requiring exceptionally long strokes, high stroking speeds, or severe temperatures. From a maintenance standpoint, pneumatic actuators are more easily serviced and calibrated than other types of actuators. Some pneumatic actuators are designed to be field-reversible, meaning that they can be converted from air-to-extend to air-to-retract (or visa versa) in the field without special tools or maintenance procedures.

2 Features of Pneumatic Actuators

In general, essential systems for power transmission in machineries are pneumatic, hydraulic, electric, and mechanical. By making comparisons with these systems, the features of the pneumatic actuators can be enumerated as below:

(1) Compared to hydraulic systems, pneumatic systems are more suitable for light and medium loads. In reciprocating air compressors, since the discharge pressure at the first and the end stage are 600~700 kPa and 1200~1400 kPa respectively, the air pressure mostly utilized is below 1000kPa. As pressure higher than this, the efficiency suffers, and its use become difficult as the system has to conform to the applicable rule requirements for high-pressure gas.

(2) The best feature of compressed air is that, by utilizing the compressibility characteristics of air, energy can be stored in the form of pressure in air tanks. This can be used for high-speed operations or emergency operations during power failures.

In addition, during the momentary air consumption of the pneumatic machine, even if it exceeds the discharge volume of the air compressor, work greater than the capacity of the air compressor can be done with the provision of air tanks etc provided that the average air consumption (value obtained by dividing the total consumed by the sum of the operating and idling time of the air compressor) is not exceeded.

(3) Control of position and speed is difficult due to the compressibility characteristics of air.

(4) Due to various losses involved, the overall efficiency of the pneumatic actuator, in comparison with the other systems is low. In an air compressor, theoretical work is done in adiabatic compression but the volume gets reduced when the compressed air is cooled. Moreover, there is pressure loss when compressed air is sent to the pipings and the control valves and form the air tank and in addition if it is assumed that there are leakages on the way then there is reduction in its volume by the time it reaches the pneumatic actuator. If the pneumatic actuator is of the complete-expansion type, the work done can be effectively used in a non-expansion type, this degree of advantages is further reduced.

(5) Due to the compressibility characteristics of air, no surge pressure similar to that which occurs in the hydraulic system is generated which obvious the necessity of overload prevention

device in the system, and also the mutual interference between the machines due to the surge pressure is low.

Furthermore, as the output in the pneumatic actuator does not exceed the theoretical output, it is safe. This allows the theoretical output to be calculated from the useable air pressure only without taking into account the surge pressure.

(6) Piping is easier than in the hydraulic system and also no environmental pollution problem or fire risk due to external leakages.

(7) Pressure loss is small, because inertia and viscosity of the air are small compared to the hydraulic fluid. Air can be piped to each and every part of the factory and used readily. The maintenance is also easy.

(8) It has a large range of practical application because it can be adopted for wide range of temperature, vibration and combustion environments.

The useable temperature is rather wide, -40 to 200 and thus especially suitable where consideration in the specification must be given to prevent freezing of moisture contents and use of seals and electrical parts at low temperatures.

(9) Pneumatic actuators have no fire hazards and are made of explosion proof construction.

(10) It is easy to convert electrical signals to pneumatic, pneumatic to hydraulic, and pneumatic to electrical signals. As opposed to the response in electrical signal systems, it is inferior for the control elements in the pneumatic systems.

3. Two Kinds of Pneumatic Actuators

The most commonly applied pneumatic actuator over the past 40 years has been the diaphragm actuator (See Figure 7.5). Most diaphragm actuators are designed for linear motion, although some rotary-motion designs exist. By definition, a typical diaphragm actuator is a single-acting actuator that provides air pressure to one side of an elastomeric barrier (called the diaphragm) to extend or retract the actuator stem, which is connected to the closure element. The diaphragm is sandwiched between upper and lower casings, either of which can be used to hold air pressure, depending on the style of the actuator.

Diaphragm actuators have both direct-acting designs. With the direct-acting design, air pressure is sent to the actuator, which extends the actuator stem and allows the value to close. This also means that the actuator will retract its stem upon loss of air, allowing the value to open and remain open. With the reverse-acting design, as the air pressure is sent to the actuator, the stem retracts and the value opens. If the supply or signal air pressure is interrupted, the actuator moves to the extended position, allowing the value to close.

The chief advantage of diaphragm actuators is that they are relatively inexpensive to produce and are commonly seen through the entire process industry. Although limited in high-thrust requirements, they are well suited to a good portion of applications in lower-pressure ranges, where thrust requirements are not so demanding. On the other hand, diaphragm actuators —because of the limitations of the diaphragm — do not provide exceptional stiffness and therefore have problems with fluctuations in the process flow. They also experience problems when throttling close to the seat, not having enough power to prevent the closure element from being pulled into the seat. The stiffness value of a diaphragm actuator is usually constant throughout the entire stroke. When the closure element is close to the seat, a sudden change or fluctuation in the process flow can cause the valve to slam shut, causing water-hammer effects.

From a maintenance standpoint, the life of diaphragm actuators is somewhere limited by the

life of the diaphragm. If the diaphragm develops even a minor failure, the actuator is inoperable. Since the two casings are bolted together with numerous bolts, disassembly can be somewhat laborious and time consuming. Diaphragm actuators are not field-reversible, because different parts are required for the direct and reserve-acting designs. Diaphragm actuators have about one-third more parts than other types of pneumatic actuators, which increasing their cost somewhat.

Although the diaphragm actuator is the most common pneumatic actuator, the piston cylinder actuator (See Figure 7.6) is gaining widespread acceptance, especially as processes become more advanced and demanding. The piston cylinder actuator uses a sliding sealed plate (called the piston ) inside a pressure-retaining cylinder to provide double-acting operation. With the double-acting design, air is supplied to both sides of the piston by a positioned. As with all double-acting actuators, a positioner must be used to take the pneumatic or electric signal from the controller and send air to one side of the piston while bleeding the opposite side until the correction position is reached. An opposing range spring is not necessary with the piston cylinder actuator, although a spring may be included inside the cylinder to act as a fail-safe mechanism.

Like diaphragm actuator designs, piston cylinder actuators can be used with either linear or rotary valves. Linear designs are the most efficient since the entire movement of the actuator stem is transferred directly to the valve stem. On the other hand, the rotary design must use some type of linear to rotary-motion linkage. This can create some hysteresis and dead band v\because of the lost motion caused by the use of linkages of slotted levers.

The primary advantage of cylinder actuators is the higher thrust capability, size for size, over comparable diaphragm actuators. Because the cylinder actuator with a positioner does not need to use air supply as a signal, the plant’s full air-supply pressure can be used to power the actuator. The piston with its sliding O-ring seal is much more capable of handing greater air pressure than the diaphragm. Piston actuators, which have smaller chambers to fill with higher pressure of air, have faster stroking speeds than diaphragm actuators, which must fill larger chambers with lower pressure of air, piston cylinder actuators are much more compact, being smaller in height and weight, than diaphragm actuators —an important consideration with installation, maintenance, and seismic requirements.

Piston cylinder actuators have some drawbacks. First, if the actuator remains in a static position for some time, some breakout force may be necessary to move the piston when a signal is eventually sent. When considering the added thrust and response associated with piston cylinder actuators, this breakout torque may not be noticeable. The requirement of a positioned does add expense to the actuator—although with less parts, the actuator itself is less expensive than a diaphragm actuator. A positioned also requires calibration.

技术参数和性能

Cv3000系列HLC小口径套筒单座调节阀 Cv3000 serials HLC small-size sleeve single-seated regulating valves 概述 General HLC小口径套筒调节阀是一种高性能的调节阀，适用于 流体压差超过3MPa的高压差场合。坚固的阀芯导向和套筒 可防止液体发生闪蒸和空化。阀体结构紧凑，呈S流线型通 道，压降损失小、流量大、可调范围广等优点，配用多弹簧式 薄膜执行机构，使其结构紧凑、输出力大，广泛应用于工业过程的自动控制中。 HLC small-size sleeve regulating valves, a high-performance regulating type suitable for the applications where the high differential pressure exceeding 3 MPa, have been designed with a sturdy core guide and sleeve to prevent the liquid from occurring flash vaporization and cavitation. The product, with a compact body structure and S-shaped flow channel, features a low pressure drop loss, large flow and wide adjustable range. It’s used with multi-spring diaphragm actuators which have a compact structure and large output force, and widely used for the automatic control in the industrial processes. 技术参数和性能 Technical parameters and performance 阀体 Body 阀体型式：直通单座套筒式铸造球型阀 公称通径：20、25mm 公称压力：ANSI 125、150、300、600 JIS 10、16、20、30、40K

Sensors and Actuators APhysical

Sensors and Actuators A:Physical 1.Introduction At present several wireless capsule endoscopy systems areavailable on the market(Given Imaging,Olympus EndoCapsule)[1].Although appealing to the patient for comfort reasons,they lack three major properties:adequate image resolution (256×256 pixels),sufficient frame rate(2–7 frames per second (fps)),and the ability to move around in a controlled way through the GI tract.These shortcomings hamper their breakthrough with gastro-enterologists,who still prefer the traditional endoscopes[2]. These limitations are a direct consequence of the finite energy supply available in these capsular endoscopes.All of them being battery powered,their lifetime is limited between 6 and 8 h,consuming 25 mW.The tight energy limit does not exist in the case of inductive powering[3,25]. Without the energy constraint,a higher resolution sensor and higher frame rates become possible.However,in order to get the mass of image data outside the body to the receiver,a high speed data transmitter is required. 2.Requirements 2.1.Data rate Moderm wired endoscopes are already equipped with High-Definition(HD)CCD cameras, providing up to 30 fps at 1920×1080 pixels per frame[4].This resolution would requirea raw Bayer data rate of 78 MByte/https://www.sodocs.net/doc/011282887.html,D image sensors are not suitable for use in capsular endoscopes because of their high power consumption compared to their CMOS equivalent. HD resolution in wireless endoscopy,even highly compressed,sounds like a fairy tale,for the simple reason that high data rate and low power is hard to combine.It is a questionable prognosis if the big advantage of patient comfort will surpass the need for HD image resolution. Compared to the presently used 256×256 pixel resolution,a big improvement in image quality can already be obtained by using a 640×480 pixel(VGA)image sensor. For 10 fps,which is a major step ahead of the current 2 fps,a raw Bayer data rate of 3.84 MByte/s is required. Still being too high for low power transmission,appropriate compression algorithms have to be used to reduce the raw data rates to acceptable levels suitable for low power transmission. https://www.sodocs.net/doc/011282887.html,pression Image compression basically removes visually redundant information from a picture or video stream,without exaggerated loss of detail or introduction of compression artifacts. The (lossy) compression algorithms are either based on removal of high frequency image content(e.g.JPEG)or on removing redundancy from the image colors[5].A20-fold compression can easily be reached without disturbing artifacts or visual image degradation.This will relax the data rate requirement to a more feasible 1.5 Mbps. The choice of the compression engine is important at system level design:depending on the type of compression more bulky and power consuming RAM is needed. 2.3.Carrier frequency and modulation Little research has been done on the choice of the carrier frequency for through-body wireless near-field transmission.

SIEMENS快速执行器

4609 OpenAir TM Fast running actuators for air dampers GNP19… Fast runner rotary version with electronic fail-safe function, AC/DC 24 V Electronic rotary actuator for 2-position, 3-position, or modulating control, nominal torque 6 Nm, at 2 s running time, with electronic fail-safe function; self- centering shaft adapter, range mechanically adjustable between 0...90°, prewired with 0.9 m long standard connection cables. GNP196.1E with adjustable auxiliary switches for auxiliary functions. Use ?For damper areas up to 1 m2, friction dependent. ?For laboratory fume hoods, etc. ?Suitable for use with continuous, 2-position, or 3-position controllers. CE1N4609en

2/5 Type summary Types Power Auxiliary switch Torque Damper size Runtime GNP191.1E No GNP196.1E AC/DC 24 V Yes 6 Nm Ca. 1 m 2 2 s The actuators preset at the factory to: ? 0… 10 V ? Clockwise rotary movement ? Counter-clockwise fail-safe movement Functions DIL switch setting A DIL switch is used to set the actuator's functionality. Siemens default setting Modulating control 2-position control 3-position control Position indication: Mechanical Rotary angle position. Position indication: Electric. Output voltage U = DC 0...10 V is generated proportional to rotary angle. U depends on the DIL switch's rotary direction position. Rotary angle limitation The rotary angle of the shaft adapter can be limited mechanically to 5° increments. GNP196.1E auxiliary switch The switching points for auxiliary switches A and B can be set mutually independent in 5° increments from 0 to 90°. Factory setting

BEQ电动执行器英文说明书

GENERAL INFORMATION 1.0 ACTUATOR MOUNTING 2.0 EXTERNAL PARTS STANDARD MODEL 3.0 INTERNAL PARTS STANDARD MODELS 4.0 WIRING DIAGRAM 5.0 POWER REQUIREMENTS 6.0 DUTY CYCLE 7.0 HANDWHEEL AND DECLUTCHING 8.0 MECHANICAL TRAVEL STOPS ADJUSTMENT 9.0 ELECTRICAL CONNECTION AND PRELIMINARY TEST 10.0 LIMIT SWITCH SETTING 11.0 TORQUE ADJUSTMENT 12.0 ANTI-CLOCKWISE CLOSE SETTING 13.0 HEATER 14.0 LUBRICATION 15.0 INDICATOR SETTING 16.0 MAINTENTANCE 17.0 STORAGE 18.0 TOOLS 19.0 ACTUATOR MOUNTING DETAILS ISO 5211 20.0 ACTUATOR DRIVE BUSH DETAILS 21.0 TROUBLE SHOOTING 22.0

1.0 General Information HQ series electric actuators are design to provide reliable and efficient operation of 90 degree quarter turn valves, dampers, etc. Actuator torques range from 80Nm to 3,000Nm, currently ten models are available: BEQ-A/B/C/D/E BEQ Standard Features Enclosure Rated Weatherproof IP67, NEMA 4 & 6 Enclosure High grade aluminium alloy, corrosion coated Power Supply 110/220VAC 1 PH 50/60Hz, 380/440VAC 3PH 50/60Hz, ±10% Duty Cycle EC 34 S2 (25~30%) Motor Reversible Induction motor Limit Switches 2 x open/close SPDT, 250VAC 10A rating Auxiliary Limit Switches 2 x open/close SPDT, 250VAC 10A rating (except BEQ-A1) Torque Switches Open/close SPDT, 250VAC 10A Rating (except BEQ-A1) Stall Protection Built –in thermal protection Travel Angle 90 degree +/- 10% Indicator Continuous position indicator Manual Override Declutching mechanism Self Locking Provided by double worm gearing Mechanical Travel Stops 2 x external adjustable mechanical travel stops Space Heater 5~10W Anti-Condensation. Conduit Entries 2 x PF3/4” Lubrication Grease moly EP Ambient Temperature -20 deg C ~ + 70 dec C (except on CPT & PCU board ) External Coating Dry powder polyester, Munsell No. 5R 3.5/12 Pre-Installation Inspection Verify the actuators nameplate to insure correct model number, torque, operating speed, voltage and enclosure type before installation or use. It is important to verify that the output torque of the actuator is appropriate for the torque requirements of the valve and that the actuator duty cycle is appropriate of the intended application 2.0 Actuator Mounting Do not lift the actuator by the handwheel The actuator may be mounted in any position The BEQ- Series actuators are supplied with a female d rive output. ISO5211. Bolt patterns are provided for actuator mounting. The actuator drive bush is removable for ease of machining. It is mandatory that the actuator be firmly secured to a sturdy mounting bracket or directly mounted to the valve’s ISO mounting pad. High tensile bolts or studs with spring locking washers must be used. The valve output shaft must be inline with the actuator output drive to avoid side-loading the shaft. To avoid any backlash no flexibility in the mounting bracket or mounting should be allowed.

非线性系统最优控制理论综述

非线性系统最优控制理论综述 时间：2015-06-17 作者：马玲珑 摘要：非线性系统，其最优控制求解相当困难，寻求近似的最优控求解方法是当下解决这一问题的主要途径。目前，比较成熟的最优控制求解方法主要有七类，本文对这七种方法进行了详细的阐述，并对其优缺点进行了客观的对比。 论文关键词：非线性,最优控制 近年来，最优控制理论[1,2]的研究，无论在深度和广度上，都有了很大的发展，已成为系统与控制领域最热门的研究课题之一，取得了许多研究成果。同时，也在与其他控制理论相互渗透，出现了许多新的最优控制方式，形成了更为实用的学科分支。例如鲁棒最优控制[3]、随机最优控制[4]、分布参数系统的最优控制[5]、大系统的次优控制[6]、离散系统的最优控制及最优滑模变结构控制[7,8]等。而对于非线性系统，其最优控制求解相当困难，需要求解非线性HJB方程或非线性两点边值问题，除简单情况外[9]，这两个问题都无法得到解析解。因此，许多学者都致力于寻求近似的求解方法[10~13]，通过近似解得到近似的最优控，即次优控制。 1、非线性最优控制理论研究成果分类 目前，较为流行的近似最优控制求解方法主要有以下几类[6][13]。 1）幂级数展开法：幂级数展开方法通过一个幂级数来构造控制律，得到序列形式的近似最优解，或者将系统中的非线性项以幂级数形式分解，或者通过引进一个临时变量并围绕它展开。 将上式代入HJB方程求得级数近似解，也可利用Adomian分解将非线性项进行分解，由此寻求非线性HJB方程级数的近似解。 2）Galerkin逐次逼近方法：由动态规划得到的一般性偏微分HJB方程，引入一个迭代过程来求解一般非线性HJB方程的一个近似解序列。 3）广义正交多项式级数展开法：其主要思想是将最优控制问题中的状态变量，控制输入，性能指标和各个参数分别用广义正交多项式展开，利用广义正交多项式的积分、乘积运算阵 将描述系统的微分方程转化为一系列的代数方程。然后，得到 ，T非奇异时由得到的控制律是一个多项式级数解。该方法将最优控制问题转化为代数极值问题，从而避免了求解时变非线性Riccati方程。 4）有限差分和有限元方法：经典的有限差分和有限元方法可以用来近似求解非线性

美国爱诺执行器

美国爱诺气动执行器USA ALLIED SERIES PNEUMATIC ACTUATORS

1 2 34 5 6 7 8 9 Versa View Continuous Indicator Stainless Steel Fasteners Namur Mounting Namur Manifold ISO Mounting Bi-Directional Stroke Adjustment 可视指示器不锈钢紧固件 NAMUR标准安装孔NAMUR标准安装孔 双位调节 ISO标准安装孔

在常温工作条件下使用丁腈橡胶，在高温或低温时采用氟橡胶或硅橡胶。 NBR rubber O-rings provide trouble-free operation at standard temperature ranges.For high and low temperature applications Viton or Silicone. The pinion is high-precision and integrative, made from nickelled-alloy steel, full conform to the lastest standards of ISO5211, DIN3337, NAMUR.The dimensions can be customized and the stainless steel is available. 镀镍合金钢、高精密一体式输出轴同时符合N A M U R 、ISO5211、DIN3337标准。可根据客户要求定制尺寸和不锈钢材料。 NAMUR 标准指示器便于安装位置开关、定位器等附件。 Position indicator with NAMUR is convenient for mounting accessories such as Limit Switch box,Positioner and so on. According to the different requirements, the extruded aluminum alloy ASTM6005 Body can be treated with hard anodized, powder polyester painted (different colours is available such as blue, orange, yellow etc.), PTFE or Nickel plated. ASTM6005压铸铝合金缸体可以采用硬质氧化、环氧树脂喷涂（根据要求喷涂兰色、橙色、黄色等）、PTFE涂层或镀镍满足不同要求。 压铸铝合金表面金属粉末喷涂各种颜色、PTFE涂层或镀镍处理。 Die-casting aluminum powder polyester painted in different colours ,PTFE or Nickel plated. 双活塞齿条、采用铸铝硬质氧化或者铸钢镀锌处理，安装位置对称、运作迅速、使用寿命长，简单的颠倒活塞可以改变旋转方向。 The twin rack pistons are made from Die-casting aluminum treated with Hard anodized or made from Cast steel with galvanization. Symmetric mounting position,long cycle life and fast operation, reversing rotation by simply inverting the pistons. 两个独立的行程调节螺钉可以进行方便、精确±5°的调节 开、关位置。 The two independent external travel stop adjustment bolts can adjust ±5°at both open and close directions easily and precisely. 采用优质材料、涂层处理，预压装配。具有较强的抗腐蚀性和使用寿命。能够安全、简单的拆卸单作用执行器，通过改变弹簧数量满足不同的力矩输出范围。 Preloaded coating springs are made from the high quality material for resistant to corrosion and longer service life, which can be demounted safely and conveniently to satisfy different requirements of torque by changing quantity of springs. 采用低摩擦、长寿命复合材料，避免了金属与金属的直接接触，维修更换简单方便。 Made from low friction,long-life compound material,to avoid the direct contact between metals. The maintenance and replacement are easy and convenient. 指示器Indicator Pinion 输出轴缸 体Actuator Body 端 盖End caps 活 塞Pistons 行程调节Travel adjustment 高性能弹簧 High performance springs 轴承、导板Bearings & Guides O-rings 密封 12347895 6

气动执行器ALEDER

ulletin are intended for your reference only, and should not be relied upon unless confirmed in writing by ALEDER Precision Valve Co. Ltd.. Certified dimensional drawings a available upon order receipt. Pneumatic Rotary Actuators ALEDER ISO 9001 CERTIFIED FEATURES Twin Rack and Pinion Design ? Constant Torque Output ? Compact Design ? Balanced Internal Forces ? Robust Design For Long Life Extruded Aluminum Body ? Hard Coat Anodized ? Smooth Surface Finish for Minimum Friction ? Optional Epoxy Coated or Nickel Plated ? End Caps are Die Cast Aluminum Polyester Coated Nickel Plated Pinion ? Blowout Proof ? Optional in Stainless Steel Die Cast Aluminum Pistons ? Constant Torque Output ? Optional Nickel Plating Piston Guides in PTFE / Graphite ? Large Contact Area ? Self-Lubricating, Long Life Spring Return Model SR ? Zinc Phosphate Steel Springs ? High Resistance and Reliable ? Long S.S. Bolts for safe End cap Removal External Travel Stops ? Open or Closed Positions Maximum Working Pressure and Temperature ? 150 psi for models 32 to 200 ? 115 psi for Model 270 ? Clean dry filtered air is required ? -20o C to +85o C with NBR Standard Seals ? -20o C to +150o C with Optional Viton Seals Interfaces to ISO 5211, DIN 3337, and Namur Specifications ? Direct Mount to Ball or Butterfly Valves ? Namur Drilling for Solenoid and Positioner Mounting ALEDER

美国爱诺执行器样本

美国爱诺流体控制工程有限公司 美国爱诺气动执行器 US S AL LIE SER IES P ATIC A CTUATORS U SA A A L LIED D S E R I E S PN N E U M A T I C AC T U ATO USA ALLIED SERIES PNEUMATIC ACTUATORS

1 2 3 4 5 6 7 8 9 Versa View Continuous Indicator Stainless Steel Fasteners Namur Mounting Namur Manifold ISO Mounting Bi-Directional Stroke Adjustment 可视指示器 不锈钢紧固件 NAMUR标准安装孔 NAMUR标准安装孔 双位调节ISO标准安装孔

在常温工作条件下使用丁腈橡胶，在高温或低温时采用氟橡胶或硅橡胶。 NBR rubber O-rings provide trouble-free operation at standard temperature ranges.For high and low temperature applications Viton or Silicone. The pinion is high-precision and integrative, made from nickelled-alloy steel, full conform to the lastest standards of SO5211, DI N3337, NAMUR.The dimensions can be customized and the stainless steel is available. 镀镍合金钢、高精密一体式输出轴同时符合N A M U R 、ISO5211、DIN3337标准。可根据客户要求定制尺寸和不锈钢材料。 NAMUR 标准指示器便于安装位置开关、定位器等附件。 Position indicator with NAMUR is convenient for mounting accessories such as Limit Switch box,Positioner and so on. According to the different requirements, the extruded aluminum alloy ASTM6005 Body can be treated with hard anodized, powder polyester painted (different colours is available such as blue, orange, yellow etc.), PTFE or Nickel plated. ASTM6005压铸铝合金缸体可以采用硬质氧化、环氧树脂喷涂（根据要求喷涂兰色、橙色、黄色等）、PTFE涂层或镀镍满足不同要求。 压铸铝合金表面金属粉末喷涂各种颜色、PTFE涂层或镀镍处理。 Die-casting aluminum powder polyester painted in different colours ,PTFE or Nickel plated. 双活塞齿条、采用铸铝硬质氧化或者铸钢镀锌处理，安装位置对称、运作迅速、使用寿命长，简单的颠倒活塞可以改变旋转方向。 The twin rack pistons are made from Die-casting aluminum treated with Hard anodized or made from Cast steel with galvanization. Symmetric mounting position,long cycle life and fast operation, reversing rotation by simply inverting the pistons. 两个独立的行程调节螺钉可以进行方便、精确±5°的调节 开、关位置。 The two independent external travel stop adjustment bolts can adjust ±5°at both open and close directions easily and precisely. 采用优质材料、涂层处理，预压装配。具有较强的抗腐蚀性和使用寿命。能够安全、简单的拆卸单作用执行器，通过改变弹簧数量满足不同的力矩输出范围。 Preloaded coating springs are made from the high quality material for resistant to corrosion and longer service life, which can be demounted safely and conveniently to satisfy different requirements of torque by changing quantity of springs. 采用低摩擦、长寿命复合材料，避免了金属与金属的直接接触，维修更换简单方便。 Made from low friction,long-life compound material,to avoid the direct contact between metals. The maintenance and replacement are easy and convenient. 指示器Indicator Pinion 输出轴缸 体Actuator Body 端 盖End caps 活 塞Pistons 行程调节Travel adjustment 高性能弹簧High performance springs 轴承、导板Bearings & Guides O-rings 密封 123478956结 构 Construction 爱诺.U S A

IEC IP防护、防爆等级

IEC IP防护等级 ----作者: Actuators 时间: 2007-11-13 12:29 来源: 电气论坛

二、认识电子产品的防水等级JIS(IPX) 0 无保护 1 防滴I型垂直落下的水滴无有害的影响 2 防滴II型与垂直方向成15“范围内落下的水滴无有窑的影响 3 防雨型与垂直方向成60度范围内降雨无有宾的影响 4 防溅型受任意方向的水飞溅无有害的影响 5 防喷射型任意方向直接受到水的喷射无有害的影响 6 耐水型任意方向直接受到水的喷射也不合讲人内部 7 防浸型在规定的条件下即使浸在水中也不全许人内部 8 水中型长时间浸没在一定压力的水中照样能使用 9 防湿型在相对湿度大90％以卜的湿气样能体用 国际工业标准防水登记IP和日本工业标准的JIS防水等级是接近的,分0-8的9级,IP 等级同样对防尘做了规定。 三、IPxx 防尘防水等级 防尘等级 (第一个X表示) 0 ：没有保护 1 ：防止大的固体侵入 2 ：防止中等大小的固体侵入 3 ：防止小固体进入侵入 4 ：防止物体大于 1mm 的固体进入 5 ：防止有害的粉尘堆积 6 ：完全防止粉尘进入 防水等级 (第二个X表示) 0 ：没有保护 1 ：水滴滴入到外壳无影响 2 ：当外壳倾斜到 15 度时，水滴滴入到外壳无影响 3 ：水或雨水从 60 度角落到外壳上无影响 4 ：液体由任何方向泼到外壳没有伤害影响 5 ：用水冲洗无任何伤害 6 ：可用于船舱内的环境 7 ：可于短时间内耐浸水（ 1m ） 8 ：于一定压力下长时间浸水 例：有秤或显示仪表标示为IP65，表示产品可以完全防止粉尘进入及可用水冲洗无任何伤害。

碳纳米管致动器(翻译)

Carbon nanotube actuators The exceptional electrical and mechanical properties（属性） of carbon nanotubes have made them alternatives（替代物） to the traditional electrical actuators for both microscopic and macroscopic applications. Carbon nanotubes are very good conductors（导体）of both electricity and heat, and they are also very strong and elastic molecules（分子） in certain directions. These properties are difficult to find in the same material and very needed for high performance actuators. For current carbon nanotube actuators, multi-walled carbon nanotubes (MWNTs) and bundles of MWNTs have been widely used mostly due to the easiness of handling and robustness（鲁棒性）. Solution dispersed thick films and highly ordered transparent films of carbon nanotubes have been used for the macroscopic applications. Microscopic applications--Carbon nano-tweezers Carbon nanotube tweezers(镊子） have been fabricated by deposition(沉积）of MWNT bundles on isolated electrodes （孤立的电极）deposited on tempered glass micropipettes （微型吸管）.Those nanotube bundles can be mechanically manipulated by electricity and can be used to manipulate and transfer micro- and nano-structures. Macroscopic applications—Nanotube sheet electrodes（板电极） as actuators Researchers of Allied Signal initially demonstrated（演示） the possibility of electrically powered actuators fabricated by carbon nanotube sheets.They taped carbon

美卓气动执行器

6 B 20 EN ? 6/2011 PNEUMATIC CYLINDER ACTUATORS, SERIES B The Neles double acting and spring return B-Series piston type actuators are designed for use in both modulating control and on-off service. The series B1C and B1J are designed to ISO 5211/1 when Metso linkages are utilized. These actuators offer an extremely long cycle life and are well suited to operate almost any type of rotary valve. When "stay put" is the requirement, the double acting B1C series is the choice. This series is available in several sizes with torque outputs from 40 Nm to 100 000 Nm (29.5lbf ft to 73 756 lbf ft) for maximum supply pressure of 10 bar (145 psi). If a failure mode is required, the spring return B1J series should be selected. This line offers a self-contained spring cartridge to provide failure in either the open or closed position. On butterfly valves, segmented valves and Q-ball valves, the actuator provides failure in the closed position, while a B1JA series is available when failure in the open position is required. The spring return actuators are available with a mid-range spring for 4 bar (58 psi) supply range, a lighter spring for lower supply pressure 3 bar (44 psi) range and a stronger spring for 5.5 bar (80psi) range. These actuators offer torque outputs from 50 Nm to 12 000 Nm (37lbf ft to 8851lbf ft)for maximum supply pressure 8.5 bar (124psi). Adjustable travel stops As with any Neles pneumatic/hydraulic actuator ,adjustable travel stops are standard for both the open and closed positions. End of stroke turning angle range is 85° to 95°. Optional travel stops 0° to 90° are also available. Wear resistant bearings Metal backed acetal bearings provide support on the upper and lower portions of the lever arm to reduce friction and expand the life of both the lever arm and the housing. Corrosion resistance The epoxy painted actuators have housings of rugged cast iron, with light-weight aluminium cylinders ano-dized for added corrosion resistance. Travel stops are stainless steel. Self-contained spring cartridge The springs in the B1J actuator are contained in a cartridge for added reliability and easy maintenance. Spring to open or close capability The standard spring return actuator on ball valve can provide spring-to-close or spring-to-open operation simply by changing the mounting position 90°. On a high performance butterfly valve, the standard unit offers spring-to-close operation. An optional B1JA model is available for spring-to-open requirements. High-and-low temperature construction The standard unit can be used in temperature upto 70°C (158°F). High temperature construction is availa-ble for temperatures up to 120 °C (248 °F). The standard unit can be used down to -20 °C (-4 °F). Low tempera-ture design is available down (37 lbf ft to 8851 lbf ft). High cycle option For applications where very fast and high sequency operation is required. ATEX compatibility Standard construction ATEX approved. Oversized cylinder options The oversized cylinders (B1C 60, 75, 602, 752) are used whenever the supply pressure is limeted, thus the actuators can achieve the required torques with lower supply pressure level. Override options Available override devices include a manual center-piece handle; a manual handwheel override; and a manual hydraulic override for high torque applications. Emergency shut-down Emergency Shut-Down (ESD) valves utilizing B1J actu-ators are offered to assure operation in the event of a fire or plant malfunction. The ESD device enables valve operational testing without cycling, see bulletin 6B21.