原文：
         一般来说，控制阀阀体的结，构不需要有更多的改变就适应抗地震的要求，通常阀体比管线强度高，而采用应力分析的方法也很简单。偶尔也需要利用一些技术改造，利用选择阀门尺寸和压力系数同时来满足液体处理要求和抗地震要求。

 　　阀盖： 　　从抗地震分析的观点看.阀盖可以视为一个“中间支撑结构”。管线系统的地震运动必须经过阀盖方能到达驱动装置。因此.阀盖必须能承受住驱动装置的动力学作用。对于它自身，阀盖是阀门中一个非常强的部分，然而因为它自身的基本结构，它很难精确地分析。

　　大部分控制阀阀盖用ASME一Ⅲ中的附录X1分析，尽管这个附录通常是为管线法兰的分析准备的，但被公认为可以做阀盖法兰的分析。任何位于驱动装置上的因地震导致的弯曲力解波转换成一种“高值压力”简称eq.一从而增加了阀门的设计压力，阀盖和体盖螺栓就必须能承受住这种增加的法兰结构压力，Pfd=Pd + Peq。).如果用更复杂的方法计算压力，那么计算压力将更高。因为阀盖是比需要的压力强许多，所以柱塞阀 计算压力通常在限定的许可范围之l内。 　　阀盖必须能支撑住固定在其上的驱动装置人选些驱动装置常常很大而从阀盖上延伸到一个显著的位置上，一个阀门驱动装置也许对整个系统有着明显的动力影响。正是这些动力因素导致了阀盖结构的绝大部分改变，这些结构的改变包括增加管壁和法兰厚度和重新设计驱动装置与阀盖的连接方式少受力状态，相反是增加硬度和稳定性。阀盖越是坚固，阀门各部件的总体上的固有频率就越能保持得尽可能高。

　　阀门驱动装置： 　　阀门驱动装置是最受核动力工业抗地震限定条件影响的控制阀部件，曾一度被认为本质上简单的控制阀驱动装置已被其自身证明做样品分析和为了增加固有频率而做的改进是同样困难的。正像阀门_中别的部分一样，驱动装置结构已基本上十几年保持不变了；它的设计能力已在以矿物燃料为动力的工厂，造纸厂石油精炼厂以及所有大大小小的轮船上的多年应用中得到证明，直到阀门制造商不得不通过检验证明抗地震要求.才有了设计上的改变。 　　一个驱动装置有两个基本部件，支架和动力装置，呼吸阀支架用于将驱动装置固定在阀盖上，以提供一个连接阀杆和驱动装置的位置、以及提供一个用来安装附件的位置(如弹簧膜片驱动装置中的限位开关和定位器等)。第二部分是动力源，典型的类型是弹簧膜板、气缸、液压千斤顶和电机。

 　　在大多数情况下支架由铸铁制成，旋塞阀并用一些大的紧固螺母与水盖连接在一起，然而因为必须承受像地震这样的动力负荷的需要.就必须改变设计。首先改变的是材质，最初所用的材质一铸铁非常适合最初的设计负荷，即主要的驱动一装置推力。铸铁有一个问题，它很脆的材料对于大的冲击负荷和低转疲劳负荷损坏非常敏感，因此将铸铁材料改为铸钢材料、通常是ASTM一216 WCB型，这个改变是容易实现的，因为设计和模具都是相同的.机加工也是相同的，只是材料改变而已。

　　下一个改变就比较困难，许多抗地震检验的结果证实支架和阀盖的连接必须重新设计，紧固螺母比起初的设计性能要高，然而抗地震检验的动力负荷情况结果中显露出一些问题：

      首先，支架是支撑在阀盖的小座上，这足够支撑延伸出来的驱动装置的推力负荷，因为所有组件都是受一压力作用，然而，在驱动装置的基部没有足够的支撑面来保持尽可能高的支架的坚固程度。

 　　其次，紧固螺母在抗地震检验中倾向于松动.一次地震试验的过程要比任何一次可能遇到的地震都剧烈，而且这种松动不像铸铁的断裂那样是灾难性的。尽管如此，在紧固螺母这样的关键部位的松动也是不允许的。同时，紧固螺母的松动也有其它问题，它意味着支架和阀盖间的连接一旦松动.驱动装置接着就可能绕着阀杆轴线偏转，从而导致像限位开关和定位器元件的位移而造成失控。

 　　驱动装置和阀盖两者在连接上都做了改进，设计的基本思想是在支架和阀盖问提供一个大的接触面，提供一个防止驱动装置转动和连接处的松动，使支架和阀盖间的连接更坚同。在阀盖和支架间提供一个大的接触向的设计是相当容易的。平衡阀阀盖的浇铸模型做了临时或永久地改进，以提供一个紧固驱动装置的固定法兰或是在州有阀盖上焊接一块平板.如何使驱动装置坚固可*取决于设计者的措施。连接方式见图2.它包括最初的紧固螺母结构，其它的方式有；将驱动装置根据和阀盖法兰螺栓相接或压扳放于用螺栓固定阀盖的位置上使驱动装置紧固，或者通过阀盖法兰用螺栓直接固定在支架上。 　　驱动装置设计中根据抗地震的基本原则也也进行了部分修改.这些原则包括尽可能提高强度，减轻重量和降低整体的重心。尽管(这将在后就讨论)这些改变的目的不是讨论起来十分简单，但实际上这些原则执行起来却十分困难。例如：为了提高强度就必须增加材料(增加质量)，因为动力源必须支架腿支撑，重心也只能降低到有限的程度，很多情况下为了适应抗地震必要条件就必须用结构钢安装驱动装置或额外增加支撑。

 　　通常的情形是.一个给定尺寸的标。准驱动装置必有一个在1OHz范围内的固定频率，为了抗地震需要而重新设计驱动装置几乎是进行一个全新的设计。增加基座使用螺栓固定阀盖。支架由结构钢制成。主要是槽钢，这是为了提高强度。在强度低的隔板箱上增设加同板，以消除弯曲，通过去掉多余的材料使重心降低。疏水阀结果使驱动装置在同样的阀门上有相同的功能。它的同有频率完全在33Hz之上。为了满足核电站抗地震条件要求，控制阀驱动装置经历丁相当大的结构改进。这些改进包括材料、连接方式和总体结构的设计，结果是常常用一种类型的设汁和—项工程改革，就能满足工业产口的需要。

 　　驱动装置附件： 　　驱动装置附件常见在类似弹簧膜片驱动的或气缸驱动的这些气动装置上，固定在驱动装置上的附件类型包括：限位开关，电磁阀、定位器，空气过滤调节器、空气升压器和电动气动传感器。附件的数量和类型以阀门的功能和使用者的需要为准。电和电磁液压驱动装置附件通常包括在驱动装置结构中，因此很少有问题。除此之外.它们不需要像空气接收器、电磁阀和空气升压器之类设备同时也不需要那些紊乱的气体管路。 　　在气动装置上这些附件同驱动装置相比尺寸都比其要小，这就是说附件的安装不会显著影响整个阀门部件的动力学特性。然而附件和它们的固定设备对阀门的抗地震能力确实有一定影响.

“ Nuclear power plant control valves the gradual improvement of earthquake-resistant structures ”是由中国截止阀网提供的阀门新闻，译文仅供参考。另外，中国截止阀网还提供相关产品搜索： 波纹管截止阀、 更多截止阀产品、 气动管路截止阀(仪表截止阀)、 更多截止阀产品、 截止阀价格。

译文：
         In general, the control valve in the end, configuration changes do not have more to adapt to the requirements of the earthquake, usually more than pipe body strength, while the use of stress analysis method is simple. Occasionally need to use a number of technological transformation, using selection valve size and pressure coefficient at the same time to meet the fluid handling requirements and anti-earthquake requirements. Valve cover: Anti-seismic analysis from the point of view. Valve cover can be seen as an "intermediate support structure." Pipeline system, the seismic motion can only be reached through the valve cover drives. So. Valve cover must be able to withstand the dynamic effects drive. For its own, the valve in the valve cover is a very strong part of, but because the basic structure of its own, it is difficult to accurately analyze. Most of the control valve of a valve cover with ASME Ⅲ in Appendix X1 analysis, although the appendix is usually prepared for the analysis of pipe flange, but is considered to do the analysis of valve cover flange. Any in the drive due to earthquakes on the solution of bending wave power into a "high-value pressure" for short eq. Butterfly ValvesA valve designed to increase the pressure, valve cover and body cover bolts must be able to withstand this increase Flange pressure, Pfd = Pd + Peq. ). If you use more sophisticated methods of calculating the pressure, then the calculation of the pressure will be higher. Because the valve cover is much stronger than the pressure required, so the pressure is usually calculated in the limited license within the scope of l. Valve cover must be able to support living on fixed drives in their choice much more often drive extending from the valve cover to a significant position, a valve drive the whole system may have a significant effect of power. It is these factors that led to the power structure of most of the valve cover changes, and these structural changes include increasing the pipe wall and the flange thickness and the re-design drive connection with the valve cover less stress state, the contrary is to increase the hardness and stability sex. The more rigid valve cap, valve on the components of the overall natural frequency of the more able to maintain was as high. Valve actuator: Valve actuator is the most anti-nuclear power industry, impact of seismic qualification of the control valve components, was once considered essentially a simple control valve actuators have been proven to do their own analysis of samples and to increase the natural frequency of the improvements made the same difficulties. As in other parts of the valve _ the same drive structure has basically remained unchanged a decade; its design capacity with fossil fuels in power plants, paper mills, oilBellows Seal Valves refineries, and all sizes ship for many years on the application of proven, until the valve manufacturers have passed the examination to prove anti-earthquake requirements. have the design changes. One drive has two basic parts, brackets and power equipment, support for the drive unit in the valve cover to provide a connection location of the stem and the drive and provide a location to install accessories (such as spring diaphragm drive of the limit switches and positioning, etc.). The second part is the power source, the typical spring type diaphragm, cylinder, hydraulic jacks, and motor. In most cases, stents are made from cast iron, and with some great cover fastening nut connected with the water, but because it must withstand dynamic loads such as earthquake needs. We must change the design. First of all, change is material, a material used in the original cast iron is ideal for the initial design loads, that is the main thrust of a device driver. Cast iron have a problem, it is very brittle material for a large shock load and low load transfer fatigue damage is very sensitive to the cast iron to cast steel, ASTM A 216 WCB usually type, this change is easy, because design and mold are the same. machining is the same, only material change in it. The next change is difficult, and many anti-seismic test results confirm that the connection brackets and valve cover to re-design, fastening nut design performance than the initial higher, but anti-seismic test results of dynamic loading in a number of issues have emerged: First, the stent is supported in the valve cover of a small seat, which extends out enough to support the thrust load drive, because all components are subject to a pressure, however, drives the base of the support surface is not enough to keep the highest possible level of support the firm. Second, the fastening nut in the anti-earthquake inspection tend to loose. An earthquake in the process of trialCheck Valves experience than any one could have severe earthquake, and that the loose unlike the cast iron fracture as disastrous. Nevertheless, such a key part fastening nut loosening is not allowed. At the same time, tighten loose nuts have other problems, it means the stent and valve cover, once loose connection between the. Drive around the stem axis may then deflection, resulting in limit switches and positioning devices as components of the displacement caused by out of control. Actuator and valve cover are both made in connection to improve the design of the basic idea is to ask the stent and valve cover to provide a large contact surface to provide a drive device to prevent rotation and loosening joints, so that brackets and valve cover more firm connection between the same. In the valve cover and support in providing access to a large design is very easy. Cast model of valve cover to do a temporary or permanent improvement to provide a fastening flange fixed drives or welding in the state has a flat valve cover. How to drive strong measures may * depend on the designer. Connection Figure 2. It includes the original structure of fastening nuts, other methods are; to drive and the valve cover flange bolts under phase or the pressure of pulling up on the valve cover with bolt position to drive fastening , or through valve cover flange bolts directly fixed on the stent. Drive anti-earthquake design, in accordance with the basic principles have also been partial revision. Zhexie principles, including the possible increase the strength, reduce weight and lower overall in the center of gravity. Although (this will be after the discussion) is not the purpose to discuss these changes with a very simple but in reality the implementation of these principles together is very difficult. For example: To improve the strength of the material must be increased (increasing quality), because the power source must support leg support, the focus can only be reduced to a limited extent, in many cases the necessary conditions inPlug Valves order to meet the earthquake resistance of structural steel have to install the driver with the device or additional support. The usual situation is. A given standard size. There must be a standard drive fixed within the 1OHz frequency of anti-earthquake needs to redesign the drive for almost an entirely new design. Increase the use of bolts valve cover base. Support from the structural steel. Main channel steel, which is to increase strength. Low intensity of partitions in the box on the additional increase with board, to eliminate bending, by removing excess material so that lower center of gravity. Result in the same valve drives have the same function. It totally the same frequency of 33Hz over there. In order to meet anti-seismic conditions require nuclear power plant, the control valve drive through the small significant structural improvements. These improvements include the materials, connections and overall structural design, the result is often designed with a type of juice and - of reform projects, able to meet the needs of industrial products export. Drive accessories: Drive attachment common spring-like diaphragm driven or pneumatic cylinder-driven devices these, fixed on the drive attachment types include: limit switches, solenoid valves, positioners, air filter regulator, air booster and electro-pneumatic transducer. Safety ValvesNumber and type of attachment to the valve functions and user needs prevail. Electrical and electromagnetic hydraulic drive accessories usually included in the drive structure, there are few problems. Addition. They do not need as air receivers, air solenoid valve and booster of the same class of device does not need a gas pipeline that disorder. These attachments in the pneumatic device than with the drive size is smaller than its, which means that installation of accessories not significantly affect the dynamic characteristics of the valve components. However, the fixed equipment, accessories and their ability to withstand earthquakes of the valve does have some influence.

原文来源：http://www.1jiezhifa.com/

2010-07-28 07:35

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