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1、<p><b>  附錄</b></p><p>  A Comparison of Soft Start Mechanisms for Mining Belt Conveyors</p><p>  Michael L. Nave, P.E.</p><p>  CONSOL Inc.</p><p>  1

2、800 Washington Road Pittsburgh, PA 15241 Belt Conveyors are an important method for transportation of bulk materials in the mining industry. The control of the application of the starting torque from the belt drive syste

3、m to the belt fabric affects the performance, life cost, and reliability of the conveyor. This paper examines applications of each starting method within the coal mining industry.</p><p>  INTRODUCTION</p

4、><p>  The force required to move a belt conveyor must be transmitted by the drive pulley via friction between the drive pulley and the belt fabric. In order to transmit power there must be a difference in the

5、belt tension as it approaches and leaves the drive pulley. These conditions are true for steady state running, starting, and stopping. Traditionally, belt designs are based on static calculations of running forces. Since

6、 starting and stopping are not examined in detail, safety factors are applied</p><p>  SOFT START MECHANISM EVALUATION CRITERION</p><p>  What is the best belt conveyor drive system? The answer

7、depends on many variables. The best system is one that provides acceptable control for starting, running, and stopping at a reasonable cost and with high reliability (Lewdly and Sugarcane, 1978). Belt Drive System For th

8、e purposes of this paper we will assume that belt conveyors are almost always driven by electrical prime movers (Goodyear Tire and Rubber, 1982). The belt "drive system" shall consist of multiple components inc

9、luding the ele</p><p>  Belt Drive Component Attributes Size.</p><p>  Certain drive components are available and practical in different size ranges. For this discussion, we will assume that be

10、lt drive systems range from fractional horsepower to multiples of thousands of horsepower. Small drive systems are often below 50 horsepower. Medium systems range from 50 to 1000 horsepower. Large systems can be consider

11、ed above 1000 horsepower. Division of sizes into these groups is entirely arbitrary. Care must be taken to resist the temptation to over motor or under motor </p><p>  Torque Control. </p><p>  

12、Belt designers try to limit the starting torque to no more than 150% of the running torque (CEMA, 1979; Goodyear, 1982). The limit on the applied starting torque is often the limit of rating of the belt carcass, belt spl

13、ice, pulley lagging, or shaft deflections. On larger belts and belts with optimized sized components, torque limits of 110% through 125% are common (Elberton, 1986). In addition to a torque limit, the belt starter may be

14、 required to limit torque increments that would stretch belt</p><p>  Thermal Rating. </p><p>  During starting and running, each drive system may dissipate waste heat. The waste heat may be lib

15、erated in the electrical motor, the electrical controls,, the couplings, the speed reducer, or the belt braking system. The thermal load of each start Is dependent on the amount of belt load and the duration of the start

16、. The designer must fulfill the application requirements for repeated starts after running the conveyor at full load. Typical mining belt starting duties vary from 3 to 10 starts per</p><p><b>  Cost.

17、</b></p><p>  The drive designer will examine the cost of each drive system. The total cost is the sum of the first capital cost to acquire the drive, the cost to install and commission the drive, the

18、cost to operate the drive, and the cost to maintain the drive. The cost for power to operate the drive may vary widely with different locations. The designer strives to meet all system performance requirements at lowest

19、total cost. Often more than one drive system may satisfy all system performance criterions at</p><p>  Complexity. </p><p>  The preferred drive arrangement is the simplest, such as a single mot

20、or driving through a single head pulley. However, mechanical, economic, and functional requirements often necessitate the use of complex drives. The belt designer must balance the need for sophistication against the prob

21、lems that accompany complex systems. Complex systems require additional design engineering for successful deployment. An often-overlooked cost in a complex system is the cost of training onsite personnel, or the</p>

22、;<p>  SOFT START DRIVE CONTROL LOGIC</p><p>  Each drive system will require a control system to regulate the starting mechanism. The most common type of control used on smaller to medium sized drive

23、s with simple profiles is termed "Open Loop Acceleration Control". In open loop, the control system is previously configured to sequence the starting mechanism in a prescribed manner, usually based on time. In

24、open loop control, drive-operating parameters such as current, torque, or speed do not influence sequence operation. This method presumes</p><p>  In either case, the current start is aborted and an alarm is

25、sued.</p><p>  CONCLUSION</p><p>  The best belt starting system is one that provides acceptable performance under all belt load Conditions at a reasonable cost with high reliability. No one sta

26、rting system meets all needs. The belt designer must define the starting system attributes that are required for each belt. In general, the AC induction motor with full voltage starting is confined to small belts with si

27、mple profiles. The AC induction motor with reduced voltage SCR starting is the base case mining starter for underground b</p><p>  煤礦業(yè)帶式輸送機(jī)幾種軟起動(dòng)方式的比較</p><p><b>  邁克爾·</b></p&

28、gt;<p>  1800 年華盛頓路匹茲堡, PA 15241帶式運(yùn)送機(jī)是采礦工業(yè)運(yùn)輸大批原料的重要方法。從傳送帶驅(qū)動(dòng)系統(tǒng)到傳送帶紋理結(jié)構(gòu)啟動(dòng)力矩的應(yīng)用和控制影響著運(yùn)送機(jī)的性能,壽命和可靠性。本文考查了不同啟動(dòng)方法在煤礦工業(yè)帶式運(yùn)送機(jī)中的應(yīng)用。</p><p><b>  簡(jiǎn)介</b></p><p>  運(yùn)行帶式運(yùn)送機(jī)的動(dòng)力必須由驅(qū)動(dòng)滑輪產(chǎn)生,通過滑

29、輪和傳送帶之間的摩擦力來傳遞。為了傳遞能量,傳送帶上面的張力在接近滑輪部分和離開滑輪部分必定存在著差別。這種差別在穩(wěn)定運(yùn)行、啟動(dòng)和停止時(shí)刻都是真實(shí)存在的。傳統(tǒng)傳送帶結(jié)構(gòu)的設(shè)計(jì),都是根據(jù)穩(wěn)定運(yùn)行情況下傳送帶的受力情況。因?yàn)樵O(shè)計(jì)過程中沒有詳盡研究傳送帶啟動(dòng)和停止階段的受力情況,所有的安全措施都集中在穩(wěn)定運(yùn)行階段(Harrison 1987)。本文主要集中講述傳送機(jī)啟動(dòng)和加速階段的特性。傳送帶設(shè)計(jì)者在設(shè)計(jì)時(shí)必須考慮控制啟動(dòng)階段的加速狀況,以免

30、使傳送帶和傳送機(jī)驅(qū)動(dòng)系統(tǒng)產(chǎn)生過大的張力和動(dòng)力(Suttees,1986)。大加速度產(chǎn)生的動(dòng)力會(huì)給傳送帶的紋理、傳送帶結(jié)合處、驅(qū)動(dòng)滑輪、軸承、減速器以及耦合器帶來負(fù)面影響。毫無控制的加速度產(chǎn)生的動(dòng)力能夠引起帶式傳送機(jī)系統(tǒng)產(chǎn)生諸多不良問題,比如上下曲線運(yùn)動(dòng)、過度傳送帶提升運(yùn)動(dòng)、滑輪和傳送帶打滑、運(yùn)輸原料的溢出和傳送帶結(jié)構(gòu)。傳送帶的設(shè)計(jì)需要面對(duì)兩個(gè)問題:第一,傳送帶驅(qū)動(dòng)系統(tǒng)必須能夠產(chǎn)生啟動(dòng)帶式傳送機(jī)的最小轉(zhuǎn)動(dòng)力矩;第二,控制加速度產(chǎn)生動(dòng)力在安

31、全界限內(nèi)??梢酝ㄟ^驅(qū)動(dòng)力矩控制設(shè)備來完成,控制設(shè)備可以是電子手段也可以是機(jī)</p><p>  本文主要闡述輸送機(jī)的開始和加速的過程。傳送帶設(shè)計(jì)師必須控制開始加速度防止過度張緊在傳送帶織品和力量在皮帶傳動(dòng)系統(tǒng). 強(qiáng)加速度力量可能有害地影響傳送帶織品,傳送帶接合,驅(qū)動(dòng)皮帶輪,更加無所事事的滑輪, 軸, 軸承, 速度還原劑, 并且聯(lián)結(jié)。未管制的加速度力量可能造成皮帶輸送機(jī)有垂直的曲線的系統(tǒng)性能問題,傳送帶緊線器運(yùn)動(dòng),

32、 驅(qū)動(dòng)皮帶輪摩擦損失, 材料溢出, 并且做成花彩傳送帶織品。傳送帶設(shè)計(jì)員與二個(gè)問題被面對(duì), 皮帶傳動(dòng)系統(tǒng)必須導(dǎo)致極小的扭矩足夠強(qiáng)有力開始傳動(dòng)機(jī), 和控制了這樣加速度強(qiáng)制是在安全限額內(nèi)。光滑開始傳動(dòng)機(jī)可能由對(duì)驅(qū)動(dòng)器扭矩控制設(shè)備的用途, 或機(jī)械或電子, 或組合的二完成(CEM 1979) 。</p><p><b>  軟起動(dòng)結(jié)構(gòu)評(píng)估標(biāo)準(zhǔn)</b></p><p>  什么

33、是最佳的皮帶輸送機(jī)驅(qū)動(dòng)系統(tǒng)? 答案取決于許多變量。最佳的系統(tǒng)是一個(gè)為開始, 運(yùn)行, 和終止提供可接受的控制在合理的費(fèi)用和以及高可靠性。皮帶傳動(dòng)系統(tǒng)為本文我們考慮的設(shè)計(jì)方案, 皮帶輸送機(jī)被電子頭等搬家工人幾乎總驅(qū)動(dòng)。傳送帶"驅(qū)動(dòng)系統(tǒng)" 將包括多個(gè)要素包括電子原動(dòng)力、電子馬達(dá)起始者以控制系統(tǒng), 馬達(dá)聯(lián)結(jié)、速度還原劑、低速聯(lián)結(jié)、皮帶傳動(dòng)滑輪、和滑輪閘 (Cur 1986) 。它重要, 傳送帶設(shè)計(jì)員審查各個(gè)系統(tǒng)要素的適用性對(duì)

34、特殊申請(qǐng)。為本文的目的, 我們假設(shè), 所有驅(qū)動(dòng)系統(tǒng)要素設(shè)置礦的新鮮空氣, 非允許, 面積,全國(guó)電子編碼, 條款500 防爆, 礦的表面的面積。皮帶傳動(dòng)要素歸因于范圍。某些驅(qū)動(dòng)器要素是可利用和實(shí)用的用不同的范圍。為這論述, 我們假設(shè)那皮帶傳動(dòng)系統(tǒng)范圍從分?jǐn)?shù)馬力對(duì)千位的多個(gè)馬力。小驅(qū)動(dòng)系統(tǒng)經(jīng)常是在50 馬力以下。中型系統(tǒng)范圍從50 到1000 馬力。大型系統(tǒng)可能被考慮在1000 馬力之上。范圍分部入這些組是整個(gè)地任意的。必須被保重抵抗誘惑對(duì)

35、超出馬達(dá)或在馬達(dá)之下傳送帶飛行提高標(biāo)準(zhǔn)化。驅(qū)動(dòng)器結(jié)果在粗劣的效率和在高扭矩的潛在, 當(dāng)驅(qū)動(dòng)器能導(dǎo)致破壞性超速在再生, 或過度加熱以變短的</p><p><b>  熱量評(píng)級(jí)</b></p><p>  在開始和運(yùn)行期間, 各個(gè)驅(qū)動(dòng)系統(tǒng)也許消散廢熱。廢熱也許被解放在電子馬達(dá)、電子控制、, 聯(lián)結(jié)、速度還原劑, 或傳送帶制動(dòng)系統(tǒng)。各個(gè)起始時(shí)間熱量負(fù)荷依靠相當(dāng)數(shù)量傳送帶負(fù)荷

36、和起始時(shí)間的期限。設(shè)計(jì)員必須履行被重復(fù)的起始時(shí)間的申請(qǐng)需求在運(yùn)行傳動(dòng)機(jī)以后在全負(fù)荷。典型的開采傳送帶開始的責(zé)任變化從3到10 個(gè)起始時(shí)間每時(shí)數(shù)等隔,或2到4 個(gè)起始時(shí)間在連續(xù)。被重復(fù)的開始也許要求減稅或系統(tǒng)要素。有一個(gè)直接關(guān)系在熱量評(píng)級(jí)為被重復(fù)的起始時(shí)間和費(fèi)用之間??勺兯俣?。一些皮帶傳動(dòng)系統(tǒng)是適當(dāng)?shù)臑榭刂崎_始的扭矩和速度, 但只運(yùn)行以恒定的速度。一些傳送帶申請(qǐng)會(huì)要求一個(gè)驅(qū)動(dòng)系統(tǒng)能運(yùn)行延長(zhǎng)的期間以較不比最高速度。這是有用的當(dāng)驅(qū)動(dòng)器負(fù)荷必須

37、與其它驅(qū)動(dòng)器被共享,傳送帶被使用當(dāng)處理飼養(yǎng)者為被表達(dá)的物料的費(fèi)率控制, 傳送帶速度被優(yōu)選為貨車使用費(fèi)費(fèi)率,傳送帶被使用以慢速運(yùn)輸人工或材料, 或傳送帶運(yùn)行緩慢的檢驗(yàn)或移動(dòng)速度為維護(hù)目的??勺兯俣绕鲃?dòng)將要求一個(gè)控制系統(tǒng)根據(jù)某一算法調(diào)控操作速度。再生或翻修負(fù)荷。一些傳送帶配置文件存在翻修傳送帶系統(tǒng)用品能量對(duì)驅(qū)動(dòng)系統(tǒng)的負(fù)荷的潛在。沒有所有驅(qū)動(dòng)系統(tǒng)有能力接受被重新生成的能量從負(fù)荷。一些驅(qū)動(dòng)器可能</p><p>&l

38、t;b>  費(fèi)用</b></p><p>  驅(qū)動(dòng)器設(shè)計(jì)員將審查各個(gè)驅(qū)動(dòng)系統(tǒng)的費(fèi)用。費(fèi)用合計(jì)是第一基建成本獲取驅(qū)動(dòng)器, 費(fèi)用安裝和委任驅(qū)動(dòng)器, 費(fèi)用運(yùn)行驅(qū)動(dòng)器, 和費(fèi)用的總和維護(hù)驅(qū)動(dòng)器。費(fèi)用使力量運(yùn)行驅(qū)動(dòng)器也許廣泛變化用不同的地點(diǎn)。設(shè)計(jì)員努力符合所有系統(tǒng)性能要求在最低的費(fèi)用合計(jì)。經(jīng)常超過一個(gè)驅(qū)動(dòng)系統(tǒng)也許滿足所有系統(tǒng)性能標(biāo)準(zhǔn)在競(jìng)爭(zhēng)費(fèi)用。更喜歡的驅(qū)動(dòng)器安排是最簡(jiǎn)單, 譬如一個(gè)唯一馬達(dá)驅(qū)動(dòng)通過一個(gè)唯一

39、頂頭滑輪。但是, 機(jī)械, 經(jīng)濟(jì), 和功能需求經(jīng)常需要對(duì)復(fù)雜驅(qū)動(dòng)器的用途。傳送帶設(shè)計(jì)員必須平衡對(duì)優(yōu)雅的需要反對(duì)伴隨復(fù)雜系統(tǒng)的問題。復(fù)雜系統(tǒng)要求額外設(shè)計(jì)工程為成功配置。經(jīng)常被忽略的費(fèi)用在復(fù)雜系統(tǒng)是培訓(xùn)人事部的費(fèi)用, 或停工期的費(fèi)用由于不足的培訓(xùn)。</p><p><b>  軟起動(dòng)驅(qū)動(dòng)控制邏輯</b></p><p>  各個(gè)驅(qū)動(dòng)系統(tǒng)將要求一個(gè)控制系統(tǒng)調(diào)控開始的機(jī)制。 最

40、共同的類型控制被使用在更小對(duì)中等大小驅(qū)動(dòng)以簡(jiǎn)單的外形被命名"開環(huán)加速度控制" 。 在開環(huán), 控制系統(tǒng)早先被配置程序化開始的機(jī)制以被規(guī)定的方式, 通常準(zhǔn)時(shí)根據(jù)。 在開環(huán)控制, 駕駛使用參數(shù)譬如潮流, 扭矩, 或速度不影響序列操作。 這個(gè)方法假定, 控制設(shè)計(jì)師充分地塑造了驅(qū)動(dòng)系統(tǒng)表現(xiàn)在傳動(dòng)機(jī)。 為更大或更加復(fù)雜的傳送帶, "閉合回路" 或"反饋" 控制可以他運(yùn)用了。 在閉合回路控制

41、, 在開始期間, 控制系統(tǒng)顯示器通過傳感器駕駛使用參數(shù)譬如馬達(dá)的當(dāng)前層, 傳送帶的速度, 或力量在傳送帶, 并且修改起動(dòng)程序控制, 極限, 或優(yōu)選或佩帶了參量。閉合回路控制系統(tǒng)修改開始的被應(yīng)用的力量在一臺(tái)空和充分地被裝載的傳動(dòng)機(jī)之間。 常數(shù)在數(shù)學(xué)模型與被測(cè)量的可變物有關(guān)對(duì)系統(tǒng)驅(qū)動(dòng)反應(yīng)被命名定調(diào)的常數(shù)。 這些常數(shù)必須適當(dāng)?shù)乇徽{(diào)整為成功的應(yīng)用對(duì)各臺(tái)傳動(dòng)機(jī)。 最共同的計(jì)劃為傳動(dòng)機(jī)開始閉合回路控制是車頭表反饋為速度控制和壓電池力量或驅(qū)動(dòng)力反饋為

42、扭矩控制。在一些復(fù)雜系統(tǒng), 它是中意安排閉合回路控制系統(tǒng)調(diào)整自己為各種各樣的遇到的傳動(dòng)機(jī)情況。 這被命名"能適應(yīng)的控制" 。這些極</p><p>  無論如何,當(dāng)前的起飛中止并且警報(bào)運(yùn)行。</p><p><b>  結(jié)論</b></p><p>  最好的傳送帶啟動(dòng)系統(tǒng)要求在不同的傳送帶負(fù)載條件下,能夠以合理的代價(jià)帶來可

43、靠性高的可以接受的運(yùn)行性能。但是至今沒有一個(gè)啟動(dòng)系統(tǒng)能夠達(dá)到這樣的要求。傳送帶設(shè)計(jì)者必須為每個(gè)傳送帶設(shè)計(jì)啟動(dòng)系統(tǒng)屬性??偟脕碚f,全電壓交流發(fā)動(dòng)機(jī)啟動(dòng)適合于簡(jiǎn)單結(jié)構(gòu)的小型傳送帶。減電壓SCR交流發(fā)動(dòng)機(jī)啟動(dòng)是地下中、小型傳送帶的基本啟動(dòng)方法。最新的進(jìn)展顯示,固定液體填充耦合系統(tǒng)的交流發(fā)動(dòng)機(jī)是簡(jiǎn)單結(jié)構(gòu)中、大型傳送帶基本啟動(dòng)方法。對(duì)于那些大、中型而且需要重復(fù)啟動(dòng)的復(fù)雜結(jié)構(gòu)傳送帶,繞線轉(zhuǎn)子發(fā)動(dòng)機(jī)驅(qū)動(dòng)是常用的選擇。在結(jié)構(gòu)特別復(fù)雜,運(yùn)行需要不同速度的

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