空氣閥控制設(shè)計【鐵路貨車空氣制動系統(tǒng)的設(shè)計】【說明書+CAD+UG】

空氣閥控制設(shè)計【鐵路貨車空氣制動系統(tǒng)的設(shè)計】【說明書+CAD+UG】,鐵路貨車空氣制動系統(tǒng)的設(shè)計,說明書+CAD+UG,空氣閥控制設(shè)計【鐵路貨車空氣制動系統(tǒng)的設(shè)計】【說明書+CAD+UG】,氣閥,控制,節(jié)制,設(shè)計,鐵路,貨車,空氣,制動,系統(tǒng),說明書,仿單,cad,ug （學(xué)號）： 07 長春理工大學(xué)光電信息學(xué)院 畢 業(yè) 設(shè) 計（論 文）譯文 姓 名 劉飛 學(xué) 院 長春理工大學(xué)光電信息學(xué) 專 業(yè) 機(jī)械電子工程 班 級 08522 指導(dǎo)教師 吳翠紅 2012 年 4 月 28 日 Pneumatic system and various valve basic introduction Pneumatic systems use pressurized gases to transmit and control power. As the name implies, pneumatic system typically use air (rather than some other gas) as the fluid medium because air is a safe ,low-cost ,and readily available fluid. It is particularly safe in environments where an electrical spark could ignite leaks from system components. In pneumatic systems, compressors are used to compress and supply the necessary quantities of air. Compressors are typically of the piston, vane or screw type. Basically a compressor increases the pressure of a gas by reducing its volume as described by the perfect gas laws. Pneumatic systems normally use a large centralized air compressor which is considered to be an infinite air source similar to an electrical system where you merely plug into an electrical outlet for electricity. In this way, pressurized air can be piped from one source to various locations throughout an entire industrial plant. The compressed air is piped to each circuit through an air filter to remove contaminants which might harm the closely fitting parts of pneumatic component such as valves and cylinders. The air then flows through a pressure regulator which reduces the pressure to the desired level for the particular circuit application. Because air is not a good lubricant (contains about 20% oxygen ), pneumatics systems required a lubricator to inject a very fine mist of oil the air discharging from the pressure regulator. This prevents wear of the closely fitting moving parts of pneumatic components. Free air from the atmosphere contains varying amounts of moisture. This moisture can be harmful in than it can wash away lubricants and thus cause excessive wear and corrosion. Hence, in come applications, air driers are needed to remove this undesirable moisture. Since pneumatic systems exhaust directly into the atmosphere, they are capable of generating excessive noise. Therefore, mufflers are mounted on exhaust ports of air valves and actuators to reduce noise and prevent operating personnel from possible injury resulting not only from exposure to noise but also from high-speed airborne particles. There are several reasons for considering the use of pneumatic systems instead of hydraulic systems. Liquids exhibit greater inertia than do gases. Therefore, in hydraulic systems the weight of oil is a potential problem when accelerating and decelerating and decelerating actuators and when suddenly opening and closing valves. Due to Newton’s law of motion (force equals mass multiplied by acceleration),the force required to accelerate oil is many times greater than that required to accelerate an equal volume of air. Liquids also exhibit greater viscosity than do gases. This results in larger frictional pressure and power losses. Also, since hydraulic systems use a fluid foreign to the atmosphere, they require special reservoirs and no-leak systems use air which is exhausted directly back into the surrounding environment. Generally speaking, pneumatic systems are less expensive than less expensive than hydraulic systems. However, because of the compressibility of air, it is impossible to obtain precise controlled actuator velocities with pneumatic systems. Also, precise positioning control is not obtainable. While pneumatic pressures are quite low due to pressures can be as high as 10,000 psi. Thus, hydraulics can be high-power systems, whereas pneumatics are confined to low-power applications. Industrial applications of pneumatic systems are growing at a rapid pace. Underneath introduction is widely used in all kinds of pneumatic system valve. Valve is a widely used mechanical product in each country's economy. You can find valves commonly used in the following fields like oil, nature gas, coal, metallurgy, mining, refinery, pipe transportation, petrochemical, chemical, pharmacy, food production, power plant, water supply / drainage, heat supply, air supply, marine, vehicle, airplane, spacecraft, military, new tech, irrigation and many other flowing systems. There are self-driven valves and operated valves. Self-driven valves( like safety valve, relief valve, steam trap, check valve ) are functioning by utilizing its mechanical design or the pressure, direction of its flow medium .Operated valves( like gate valve, globe valve, ball valve, butterfly valve ) are functioning by actuator( manual, electric, hydraulic, pneumatic etc. ) or the pressure , flow direction of its medium. Due to the differences of pressure, temperature, flow, and physical-chemical character of its medium ,there are different requirements in designing and applying the pipeline system .Therefore there are numerous types of valve. GAS VALVE From the air valve operating principles of view, air valve performance will directly affect the work of compressor tanks, air valve for the following requirements: resistance losses small. Air valve size and airflow resistance losses of valves always speed and the size of the spring-loaded edge. Gas higher speed, the greater the energy losses; Spring-loaded edge too large, the loss is great resistance, the size of the air valve movement design guidelines to determine the reasonableness of the law. Air valve closed timely, rapid, not leak closed to improve the efficiency of machines and extended use period. Long life, work reliable. Life is the main factor restricting air valve and spring-loaded valves quality, the general long-term continuous operation of the compressors to life 80 hours; For mobile, short-term or intermittent operation of compressors, may require slightly more. Air valve and piston-type compressors are to the important components is one of the components easily damaged. It will have a direct impact on the displacement compressors, power consumption and reliability of operation, the current compressor is fast direction, and rotational speed limit is one of the key issues in improving air valve. Piston-type compressors typically use the "automatic valve" that the air valve is opened and closed valves on the pressure on both sides to achieve poor, and there is no other drive. PNEUMATIC VALVE Pneumatic valves regulate the temperature in the context nominal pressure and may adjust various fluids, gases and steam, pneumatic - valve closed, leakage small. Pneumatic-valve at the role of the implementing agencies could reach a gas open or gas shut purposes. Pneumatic valves regulate the pneumatic enforcement agencies and regulatory valves two. Enforcement agencies to promote the implementation of devices installed, it compressed air-driven, export thrust; Regulation valves are part of the implementation of devices to regulate direct contact with the media, regulatory medium flow. The pneumatic - valve structure with simple, reliable operation, export thrust large maintenance convenient and inexpensive, such as fire blast merits pneumatic - valve widely used for chemical, oil, metallurgical, electrical, textile and other industrial production processes autopilot and remote control. PRESSURE REGULATING VALVE pressure regulating valve is a reliance on external energy transfer medium itself was pressure changes pressure-type automatic adjustment of product, you can adjust the valve in the pressure equipment debugging process in accordance with their own processes pressure regulating valves for the guide command system set pressure after pressure regulating valves value, pressure regulating valves will be natural gas pressure regulating valves, the pressure for you to set and automatically maintain its constant, pressure regulating valves in the control room for your remote control oxygen flow downstream. Flow will be used for on-site oxygen pressure regulation and feedback to control the actual process parameters to control the distance. You can easily adjust the oxygen pressure. 氣壓系統(tǒng)及各種閥門的基本介紹 氣壓系統(tǒng)是用壓力氣體傳遞和控制動力，正如名稱所表明的那樣，氣壓系統(tǒng)通常用空氣（不用其他氣體）作為流體介質(zhì)，因為空氣是安全、成本低而又隨處可得的流體，在系統(tǒng)部件中產(chǎn)生電弧有可能點燃泄漏物的場合下（使用空氣作為介質(zhì)）尤其安全。 在氣壓系統(tǒng)中，壓縮機(jī)用來壓縮并供應(yīng)所需的空氣。壓縮機(jī)一般有活塞式、葉片式和螺旋式等類型。壓縮機(jī)基本上是根據(jù)理想氣體法則，通過減小氣體體積來增加氣體壓力的。氣壓系統(tǒng)通常考慮采用大的中央空氣壓縮機(jī)作為一個無限量的氣源，這類似于電力系統(tǒng)中只要將插頭插入插座便可獲得電能。用這種方法，壓力氣體可以從氣源輸送到整個工廠的各個角落，壓力氣體可通過空氣濾清器除去污物，這些污物可能會損壞氣動組件的精密配合部件如閥和氣缸等，隨后輸送到各個回路中，接著空氣流經(jīng)減壓閥以減小氣壓值適合某一回路使用。因為空氣不是好的潤滑劑（包括20%的氧氣），氣壓系統(tǒng)需要一個油霧器將細(xì)小的油霧注射到經(jīng)過減壓閥的空氣中，這有助于減少氣動組件精密配合運動件的磨損。 由于來自大氣中的空氣含不同數(shù)量的水分，這些水分是有害的，它可以帶走潤滑劑引起過分磨損和腐蝕，因此，在一些使用場合中，要用空氣干燥器來除去這些有害的水分。由于氣壓系統(tǒng)直接向大氣排氣，會產(chǎn)生過大噪聲，因此可在氣閥和執(zhí)行組件排氣口安裝消聲器來降低噪聲，以防止操作人員因接觸噪聲及高速空氣粒子有可能引發(fā)的傷害。 用氣動系統(tǒng)代替液壓系統(tǒng)有以下幾條理由：液體的慣性遠(yuǎn)比氣體大，因此，在液壓系統(tǒng)中，當(dāng)執(zhí)行組件加速減速和閥突然開啟關(guān)閉時，油液的質(zhì)量便是一個潛在的問題，根據(jù)牛頓運動定律（力等于質(zhì)量乘以加速度），產(chǎn)生加速運動油液所需力要比加速同等體積空氣所需的力高出許多倍。液體比氣體具有更大的粘性，這會因為內(nèi)摩擦而引起更大的壓力和功率損失；另外，由于液壓系統(tǒng)使用的液體要與大氣隔絕，故它們需要特殊的油箱和無泄漏系統(tǒng)設(shè)計。氣壓系統(tǒng)使用可以直接排到周圍環(huán)境中的空氣，一般來說氣壓系統(tǒng)沒有液體系統(tǒng)昂貴。 然而，由于空氣的可壓縮性，使得氣壓系統(tǒng)執(zhí)行組件不可能得到精確的速度控制和位置控制。氣壓系統(tǒng)由于壓縮機(jī)局限，其系統(tǒng)壓力相當(dāng)?shù)停ǖ陀?50psi），而液壓力可達(dá)10000psi之高，因此液壓系統(tǒng)可以是大功率系統(tǒng)，而氣動系統(tǒng)僅用于小功率系統(tǒng)。 下面介紹廣泛應(yīng)用于氣壓系統(tǒng)的各種閥門。 閥門是國民經(jīng)濟(jì)建設(shè)中使用極為廣泛的一種機(jī)械產(chǎn)品。閥門在石油、天然氣、煤炭、冶金、和礦石的開采、提煉加工和管道輸送系統(tǒng)中；在石油化工、化工產(chǎn)品，醫(yī)藥和食品生產(chǎn)系統(tǒng)中；在水電 、火電和核電的電力生產(chǎn)系統(tǒng)中；在城建的給排水、供熱和供氣系統(tǒng)中；在冶金生產(chǎn)系統(tǒng)中；在船舶、車輛、飛機(jī)、航天以及各種運動機(jī)械的使用流體系統(tǒng)中；在國防生產(chǎn)以及新技術(shù)領(lǐng)域里；在農(nóng)業(yè)排灌系統(tǒng)中都有大量的需求。 閥門分自動閥門與驅(qū)動閥門。自動閥門（如安全閥、減壓閥、蒸汽疏水閥、止回閥）是靠裝置或管道本身的介質(zhì)壓力的變化達(dá)到啟閉目的的。驅(qū)動閥門（閘閥、截止閥、球閥、蝶閥等）是靠驅(qū)動裝置（手動、電動、液動、氣動等）驅(qū)動控制裝置或管道中介質(zhì)的壓力、流量和方向達(dá)到啟閉目的的。由于介質(zhì)的壓力、溫度、流量和物理化學(xué)性質(zhì)的不同，對裝置和管道系統(tǒng)的控制要求和使用要求也不同，所以閥門的種類規(guī)格非常多。 氣閥 從氣閥工作原理來看，氣閥工作性能將直接影響壓縮機(jī)氣缸的工作，因此，對氣閥有如下要求：阻力損失小。氣閥阻力損失大小與氣流的閥隙速度及彈簧力大小有關(guān)。氣速越高，能量損失越大；彈簧力過大，阻力損失也大，其大小按氣閥運動規(guī)律的合理性準(zhǔn)則設(shè)計確定。氣閥關(guān)閉及時、迅速，關(guān)閉時不漏氣，以提高機(jī)器的效率，延長使用期。壽命長、工作可靠。限制氣閥壽命的主要因素是閥片及彈簧質(zhì)量，一般對長期連續(xù)運轉(zhuǎn)的壓縮機(jī)，希望壽命達(dá)8000小時以上；對移動式、短期或間歇運轉(zhuǎn)的壓縮機(jī)，要求可稍低些。 氣閥是往復(fù)活塞式壓縮機(jī)中的重要部件，也是易損壞的部件之一。它的好壞直接影響壓縮機(jī)的排氣量、功率消耗及運轉(zhuǎn)的可靠性，目前壓縮機(jī)正向高速方向發(fā)展，而限制轉(zhuǎn)速提高的關(guān)鍵問題之一就是氣閥?；钊綁嚎s機(jī)一般都采用“自動閥”，就是氣閥的開啟與關(guān)閉是依靠閥片兩邊的壓力差實現(xiàn)的，沒有其它的驅(qū)動機(jī)構(gòu)。 氣動調(diào)節(jié)閥 氣動調(diào)節(jié)閥由氣動執(zhí)行機(jī)構(gòu)和調(diào)節(jié)閥兩部組成。執(zhí)行機(jī)構(gòu)是執(zhí)行器的推動裝置，它以壓縮空氣為動力，輸出推力；調(diào)節(jié)閥是執(zhí)行器的調(diào)節(jié)部分，直接與介質(zhì)接觸，調(diào)節(jié)介質(zhì)的流量。由于氣動調(diào)節(jié)閥具有結(jié)構(gòu)簡單，動作可靠，輸出推力大，維修方便，防火防爆和價廉等優(yōu)點，氣動調(diào)節(jié)閥廣泛應(yīng)用于化工、石油、冶金、電力、輕紡等工業(yè)生產(chǎn)過程的自動調(diào)節(jié)和遠(yuǎn)程控制中。 氣動調(diào)節(jié)閥在公稱壓力和溫度范圍內(nèi)可調(diào)節(jié)各種液體、氣體和蒸氣，氣動調(diào)節(jié)閥關(guān)閉時泄漏量小。氣動調(diào)節(jié)閥按執(zhí)行機(jī)構(gòu)的作用方式可達(dá)到氣開或氣閉之目的。 壓力調(diào)節(jié)閥 壓力調(diào)節(jié)閥是一種無需外來能源而只依靠被調(diào)介質(zhì)本身的壓力變化進(jìn)行壓力自動調(diào)節(jié)的節(jié)能型產(chǎn)品，您只需在壓力調(diào)節(jié)閥設(shè)備調(diào)試過程中根據(jù)自身工藝要求在壓力調(diào)節(jié)閥的引導(dǎo)指揮系統(tǒng)上設(shè)定壓力調(diào)節(jié)閥后壓力值，壓力調(diào)節(jié)閥就會將氣源壓力調(diào)節(jié)為您設(shè)定的閥后壓力并自動維持其恒定。壓力調(diào)節(jié)閥用于您在主控室內(nèi)遠(yuǎn)程控制下有氧氣流量,流量孔板用于將現(xiàn)場氧氣壓力調(diào)節(jié)閥組實際工藝參數(shù)反饋到主控室，使您可以方便地遠(yuǎn)程調(diào)控現(xiàn)場氧氣壓力調(diào)節(jié)閥組。