資源目錄里展示的全都有，所見即所得。下載后全都有,請放心下載。原稿可自行編輯修改=【QQ：401339828 或11970985 有疑問可加】 熟料鏈板輸送機的設(shè)計 摘要：熟料入庫鏈板輸送機的正確設(shè)計是其良好運轉(zhuǎn)的前提條件。本文扼要地介紹熟料鏈板輸送機的類型、特點的基礎(chǔ)上，對其主要工藝和結(jié)構(gòu)參量等進行了較詳細的分析探討。 關(guān)鍵詞：輸送機；輸送量；輸送速度；喂料方式 Design of clinker drag chain conveyor Abstract：It is the precondition of stable running that design clinker drag chain conveyor correctly. Type and characteristics of clinker drag chain conveyor are introduced briedfly, and on base of that, aiming at the main process and structure parameter are analysed and dicnssed in detail. key words：conveyor；convey quantity；convey speed；feeding method 0 引言 水泥生產(chǎn)過程中，回轉(zhuǎn)窯熟料經(jīng)冷卻機冷卻后一般都送入熟料庫儲存，以消除生產(chǎn)的不均衡性以及熟料溫度、組分的變化影響。鑒于熟料具有較強的磨琢性，加之熟料溫度雖經(jīng)冷卻仍有可能較高等因素，熟料入庫均采用鏈式輸送機。 熟料鏈式輸送機的正確設(shè)計是其良好運轉(zhuǎn)的前提條件，本文對入庫熟料鏈式輸送機的類型、特點及設(shè)計作一扼要介紹。 1 類型及特點 1.1 裙板輸送機 裙板輸送機根據(jù)輸送槽的結(jié)構(gòu)大致分為普通盤式輸送機、帶橫擋板盤式輸送機及轉(zhuǎn)動盤式輸送機。 普通盤式輸送機其輸送槽由鋼板經(jīng)沖壓焊接而成，底板及側(cè)板均具足夠的強度和剛度，保證負載時不變形。輸送槽之間相互搭接但并不接觸，形成連續(xù)輸送表面；搭接量需滿足輸送槽經(jīng)過頭、尾輪時仍有重疊，不張口；輸送槽之間的間隙應(yīng)滿足輸送機經(jīng)過彎弧時不相互擠碰。 普通盤式輸送機用于傾斜輸送時，其傾角大小與被輸送物料的堆積角有關(guān)(一般比堆積角小5°)，對輸送熟料而言輸送傾角可達28°。 為了適應(yīng)較大的輸送傾角，在輸送槽內(nèi)可增設(shè)橫擋板。一般地，當輸送傾角＜35°，每隔一節(jié)距設(shè)置一塊擋板；當35°≤輸送傾角﹤45°，每個節(jié)距設(shè)置一塊擋板。擋板與輸送槽之間一般采用機械連接，以便于更換。 普通盤式輸送機可以有多個喂料點，但只能有一個卸料點。為了在頭、尾輪之間實現(xiàn)多點卸料，通過軌道道岔使輸送槽承載輪改向、輸送槽繞定軸轉(zhuǎn)動而實現(xiàn)卸料目的，這就是轉(zhuǎn)動盤式輸送機工作的基本原理。轉(zhuǎn)動盤式輸送機的輸送槽無論在上軌道還是下軌道均是開口朝上的，故上下兩層可同時進行不同的喂料和卸料作業(yè)，布置靈活。 轉(zhuǎn)動盤式輸送機頭尾輪結(jié)構(gòu)與其它輸送機不同，其卸料處采用的是特殊軌道結(jié)構(gòu)，因而這類輸送機用于中途需要兩個以上卸料點時優(yōu)勢才比較明顯。例如多個熟料庫庫頂布料及水泥磨磨頭倉喂料等場合。轉(zhuǎn)動盤式輸送機一般水平布置。 1.2 斗式輸送機 由于空間的限制或工藝布置緊湊的需要，在更大傾角情形下，必須采用斗式輸送機。在喂料區(qū)斗子唇邊相互搭接形成連續(xù)輸送面，不漏料。輸送傾角增大時，斗子有效利用率急劇下降。同樣輸送量時，傾角增大其所需斗子規(guī)格要增大，相應(yīng)運行部件重量增加。因此，這類輸送機的輸送傾角≤60°，較經(jīng)濟的傾角是45°。此外，由于每個斗子均是相對獨立、敞口的容器，這類輸送機還特別適用于輸送粉塵量大的物料。例如鋼鐵廠用于輸送燒結(jié)返礦。 熟料鏈式輸送機的類型及特點詳見表1。 表1 熟料鏈式輸送機的類型及特點 類 型 傾角范圍(°) 輸送速度() 最大輸送量（） 特 點 裙板 輸送機 普通型 ≤28 ～0.3 ～1000 結(jié)構(gòu)堅固，耐磨損，耐高溫，維修方便，可靠性高，但運行部件自重大，初始 投資相對較高。 帶擋板型 28～45 ～700 轉(zhuǎn)盤型 0 ～450 斗 式 輸 送 機 ～60 ～400 2 設(shè)計計算 2.1 工藝與結(jié)構(gòu)參量的確定 2.1.1 輸送量 輸送量是確定輸送機規(guī)格的重要參量。輸送量一般根據(jù)工藝要求確定，實際生產(chǎn)中鏈板輸送機喂料形式大致有非控制和控制兩種。 (1)非控制喂料方式。這種喂料方式的喂料量不是均衡的，而是波動的且無法加以控制。輸送設(shè)備能力的選擇必須滿足最大輸送量的需要。對于回轉(zhuǎn)窯冷卻機至熟料庫之間的熟料輸送機，由于回轉(zhuǎn)窯在生產(chǎn)過程中有掉窯皮、沖料的可能，故輸送機的理論輸送量應(yīng)為窯額定產(chǎn)量的1.5～2倍(窯規(guī)格大時取小值，反之取大值)。 采用這種計算方法，盡管可以避免窯峰值負荷時輸送機發(fā)生過載的可能，但在正常生產(chǎn)過程中，由于發(fā)生掉窯皮或沖料的概率相對較低，因此勢必造成輸送機在大部分工作時間內(nèi)僅以其理論輸送能力的50%～67%狀態(tài)工作，導(dǎo)致運動部件磨損的無謂增加。對此，采用調(diào)速電動機是一個較好的解決方案。即在窯峰值負荷時，采用高速輸送；窯正常負荷時，采用低速輸送。這樣可使輸送機在大部分運轉(zhuǎn)時間內(nèi)，以低速、滿負荷狀態(tài)工作，降低運動部件的磨損和沖擊載荷，延長鏈條、滾輪等的使用壽命。常用的調(diào)速方法有采用變頻電動機的無級調(diào)速和變極多速電動機的有級調(diào)速。 (2)控制喂料方式。這種喂料方式的喂料量能夠調(diào)節(jié)和控制，此時輸送機的理論輸送量按需要值計算即可，例如來自熟料庫庫底卸料裝置的熟料。 2.1.2 輸送速度 輸送速度是選擇輸送機規(guī)格的另一重要參量。同樣的輸送量可以有不同的速度。輸送速度高意味著可選用較小規(guī)格的輸送機，意味著減少運行部件的重量，同時還意味著可選用較小速比的減速器。此外，提高輸送速度，可降低鏈條中的張力，可選用較小破斷載荷的鏈條。但輸送速度高會帶來運動部件(鏈條、鏈輪、滾輪等)磨損及動載荷增加等負面作用，這是制約輸送速度提高的根本原因。因此輸送速度必須綜合考慮。對熟料鏈式輸送機而言，輸送速度不宜超過0.3 m/s。 2.1.3 傾角 傾角大小反映輸送機工藝布置的緊湊程度。傾角對輸送機的填充率影響較大，常用傾角系數(shù)表示。傾角系數(shù)除與傾角直接有關(guān)外，還與運行部件的結(jié)構(gòu)(如節(jié)距、側(cè)板擋邊高度、擋板間距、斗高等)有關(guān)。當傾角大于60°時，傾角系數(shù)很小以至工程設(shè)計中不再考慮這種布置形式。 2.1.4 輸送機規(guī)格 輸送機規(guī)格以底板(或斗子)的寬度表示。每一寬度有幾種側(cè)板(或斗子)高度，以適應(yīng)不同的輸送量的要求。高度增加，傾角系數(shù)提高。底板(或斗子)寬度除滿足輸送量要求外，還與上游喂料設(shè)備的規(guī)格有關(guān)(如冷卻機)，應(yīng)當注意兩者之間的匹配，滿足寬度方向布料的均勻性。底板擋邊(或斗子)高度的選擇必須滿足布料容易、運行部件運動穩(wěn)定、彎弧段不干涉及物料易于卸空等要求。在滿足輸送量的情況下，優(yōu)先選用小寬度、大高度的輸送機。 熟料輸送機規(guī)格與窯產(chǎn)量的大致關(guān)系見表2。 表2 熟料輸送機規(guī)格與窯產(chǎn)量的關(guān)系 窯產(chǎn)量 （） 輸送機規(guī)格 寬度（） 理論輸送量 （） 60～1000 500～630 50～80 10～2000 630～800 80～150 20～4000 800～1000 150～270 40～6000 100～1200 270～380 2.1.5 鏈條與鏈輪 鏈式輸送機牽引鏈條一般為套筒滾子鏈或鍛鏈。輸送機規(guī)格超過630 mm時，采用雙鏈，630 mm以下，可采用單鏈。鏈條的參數(shù)主要是節(jié)距和破斷載荷。常用的鏈條節(jié)距為250mm和315mm，根據(jù)鏈條實際所受的最大張力，再考慮一定的安全系數(shù)，選擇破斷載荷合適的鏈條。 齒數(shù)一般采用奇數(shù)齒，為提高鏈輪的壽命，常采用雙切齒。鏈輪齒數(shù)與承受的載荷、輸送速度、運動的平穩(wěn)性等有關(guān)。在輸送速度、節(jié)距不變的情況下，齒數(shù)愈多，鏈輪轉(zhuǎn)速愈低，輪齒單位時間內(nèi)的嚙合次數(shù)愈少。輪齒愈厚，鏈輪壽命愈長，但鏈輪軸所受扭矩增大，并須選用較大速比的減速器。 2.1.6 逆止器與制動器 逆止器與制動器的作用不盡相同。逆止器是為防倒轉(zhuǎn)而設(shè)置的；制動器是為減速和保持停止狀態(tài)而設(shè)置的。對逆止器而言，當系統(tǒng)重新啟動后，逆止自動減除；對制動器而言，只有當制動人工消除后，輸送機方可繼續(xù)運行。 傾斜向上輸送時，若由于突然停電或緊急停車，輸送機可慣性停車，故一般不需設(shè)置制動器，但由于承載段仍存有物料，輸送機會逆轉(zhuǎn)，導(dǎo)致飛車事故，故需設(shè)置逆止器。 2.2 計算 2.2.1 計算步驟 根據(jù)理論輸送量、輸送速度、傾角大小確定輸送機的類型及規(guī)格；再根據(jù)輸送機的工藝布置(主要是輸送機頭尾輪水平投影長度和輸送高度)，計算所需的功率和牽引鏈條張力，選擇具有一定安全系數(shù)的鏈條，配置傳動系統(tǒng)。 2.2.2 功率的計算 鏈式輸送機的動力消耗在：提升物料至要求高度所需的動力、克服空載運動阻力、克服頭尾輪轉(zhuǎn)動阻力、克服運行部件振動、彎曲(彎弧段、頭尾輪處)以及空氣阻力等。 在設(shè)計中可采用下式簡易公式計算功率。只有當據(jù)此公式計算選擇的電動機或減速器面臨跳檔時，為慎重起見，再采用逐點張力法進行校核。 式中：—理論輸送量，； —送高度，； —頭尾輪水平投影長度，； —輸送速度，； —運行部件單位長度重量，； —阻力系數(shù)(與承載滾輪的結(jié)構(gòu)形式有關(guān)，一般在0.04～0.06)； —考慮頭尾輪、彎弧段阻力、空氣阻力對功率的影響，一般在1～3 kW。 有了功率，可很方便地選擇電動機及減速器，并計算出牽引鏈條的最大張力。 3 結(jié)語 以上是熟料鏈板輸送機設(shè)計中主要的工藝和結(jié)構(gòu)參量確定的一般原則，實際設(shè)計過程中，應(yīng)根據(jù)具體情況加以選擇，以滿足工況要求。 參 考 文 獻 1.化工部起重運輸設(shè)計技術(shù)中心站組織編寫，梁庚煌主編.運輸機械手冊[M]. 北京：化學(xué)工業(yè)出版社，1983. 2.延吉生.大力推進煤矸石綜合利用促進資源環(huán)境的持續(xù)發(fā)展[J].中國礦業(yè)，2002(6). 3.冷發(fā)光.煤矸石綜合利用的研究與現(xiàn)狀[J].四川建筑科學(xué)研究，2000(2). 4.陳龍德.煅燒煤矸石作混合材改善水泥性能、降低成本[J].福建建材，2000(5). 5.姚嶸，張玉波.以過火煤矸石為立窯混合材生產(chǎn)高標號水泥[J].煤炭加工與綜合利用，2001(5). 6 The Design of High Speed Belt Conveyors G. Lodewijks, The Netherlands. SUMMARY This paper discusses aspects of high-speed belt conveyor design. The capacity of a belt conveyor is determined by the belt speed given a belt width and troughing angle. Belt speed selection however is limited by practical considerations, which are discussed in this paper. The belt speed also affects the performance of the conveyor belt, as for example its energy consumption and the stability of it's running behavior. ENERGY CONSUMPTION Clients may request a specification of the energy consumption of a conveyor system, for example quantified in terms of maximum kW-hr/ton/km, to transport the bulk solid material at the design specifications over the projected route. For long overland systems, the energy consumption is mainly determined by the work done to overcome the indentation rolling resistance . This is the resistance that the belt experiences due to the visco-elastic (time delayed) response of the rubber belt cover to the indentation of the idler roll. For in-plant belt conveyors, work done to overcome side resistances that occur mainly in the loading area also affects the energy consumption. Side resistances include the resistance due to friction on the side walls of the chute and resistance that occurs due to acceleration of the material at the loading point. The required drive power of a belt conveyor is determined by the sum of the total frictional resistances and the total material lift. The frictional resistances include hysteresis losses, which can be considered as viscous (velocity dependent) friction components. It does not suffice to look just at the maximum required drive power to evaluate whether or not the energy consumption of a conveyor system is reasonable. The best method to compare the energy consumption of different transport systems is to compare their transport efficiencies. 1 TRANSPORT EFFICIENCY There are a number of methods to compare transport efficiencies. The first and most widely applied method is to compare equivalent friction factors such as the DIN f factor. An advantage of using an equivalent friction factor is that it can also be determined for an empty belt. A drawback of using an equivalent friction factor is that it is not a 'pure' efficiency number. It takes into account the mass of the belt, reduced mass of the rollers and the mass of the transported material. In a pure efficiency number, only the mass of the transported material is taken into account. The second method is to compare transportation cost, either in kW-hr/ton/km or in $/ton/km. The advantage of using the transportation cost is that this number is widely used for management purposes. The disadvantage of using the transportation cost is that it does not directly reflect the efficiency of a system. The third and most "pure" method is to compare the loss factor of transport . The loss factor of transport is the ratio between the drive power required to overcome frictional losses (neglecting drive efficiency and power loss/gain required to raise/lower the bulk material) and the transport work. The transport work is defined as the multiplication of the total transported quantity of bulk material and the average transport velocity. The advantage of using loss factors of transport is that they can be compared to loss factors of transport of other means of transport, like trucks and trains. The disadvantage is that the loss factor of transport depends on the transported quantity of material, which implies that it can not be determined for an empty belt conveyor. 2 INDENTATION ROLLING RESISTANCE For long overland systems, the energy consumption is mainly determined by the work done to overcome the indentation rolling resistance. Idler rolls are made of a relatively hard material like steel or aluminum whereas conveyor belt covers are made of much softer materials like rubber or PVC. The rolls therefore indent the belt's bottom-cover when the belt moves over the idler rolls, due to the weight of the belt and bulk material on the belt. The recovery of the compressed parts of the belt's bottom cover will take some time due to its visco-elastic (time dependent) properties. The time delay in the recovery of the belt's bottom cover results in an asymmetrical stress distribution between the belt and the rolls, see Figure 1. This yields a resultant resistance force called the indentation rolling resistance force. The magnitude of this force depends on the visco-elastic properties of the cover material, the radius of the idler roll, the vertical force due to the weight of the belt and the bulk solid material, and the radius of curvature of the belt in curves in the vertical plane. Figure 1: Asymmetric stress distribution between belt and roll It is important to know how the indentation rolling resistance depends on the belt velocity to enable selection of a proper belt velocity. Figure 2: Loss factor (tanb) of typical cover rubber Firstly, the indentation rolling resistance depends on the vertical load on the belt, which is the sum of the belt and the bulk material weight. If the vertical load on the belt decreases with a factor 2 then the indentation rolling resistance decreases with a factor 2.52 (2 ^4/3). The bulk load decreases with increasing belt speed assuming a constant capacity. Therefore, the indentation rolling resistance decreases more than proportionally with increasing belt speed. Secondly, the indentation rolling resistance depends on the size of the idler rolls. If the roll diameter increases with a factor 2 then the indentation rolling resistance decreases with a factor 1.58 (2 ^2/3). In general the idler roll diameter increases with increasing belt speed to limit the bearing rpm's to maintain acceptable idler life. In that case the indentation rolling resistance decreases with increasing belt speed. Thirdly, the indentation rolling resistance depends on the visco-elastic properties of the belt's cover material. These properties depend on the deformation rate, see Figure 2. The deformation rate in its turn depends on the size of the deformation area in the belt's bottom cover (depending on belt and bulk load) and on the belt speed. In general the indentation rolling resistance increases with increasing deformation rate (and thus belt speed), but only to a relatively small account. Fourthly, the indentation rolling resistance depends on the belt's bottom cover thickness. If the bottom cover thickness increases with a factor 2 then the indentation rolling resistance increases with a factor 1.26 (2 ^1/3). if a bottom cover is increased to account for an increase in belt wear with increasing belt speed, then the indentation rolling resistance increases as well. It should be realized that the indentation rolling resistance, although important, is not the only velocity dependent resistance. The rolling resistance of the idler rolls for example depends on the vertical load as well as on their rotational speed. The effect of the vertical load, which directly depends on the belt speed, is large. The effect of the rotational speed is much smaller. Another resistance occurs due to acceleration of the bulk solid material at the loading point. This resistance increases quadratically with an increase in belt speed assuming that the bulk material falls straight onto the belt. This will affect smaller, in plant belt conveyors in particular. 3 RUBBER COMPOUNDS The indentation rolling resistance depends on the visco-elastic properties of the belt's bottom cover as discussed in the preceding section. This implies that the rolling resistance can be decreased by selecting a special low indentation rolling resistance (rubber) compound that is available on the market today. A small premium has to be paid for this special compound, but costs can be limited by applying it for the bottom cover only and using a normal wear-resistant compound for the carrying top cover. In that case turnovers are required to fully use the energy saving function of the bottom compound. A Quantitative indication of the level of indentation rolling resistance is the indentation rolling resistance indicator tan/E ^1/3, where tan is the loss angle and E' the storage modulus of the compound. Compounds with a reasonable indentation rolling resistance performance have indicators below 0.1. Figure 3 shows these indicators for typical medium to good performing rubbers. As can be seen in that figure, the choice for a specific rubber compound affects the energy consumption of the belt conveyor, in particular as a function of the ambient temperature. One comment (warning) must be made. A special belt with low indentation rolling resistance compound should never be selected if only one conveyor belt manufacturer offers it. In that case the conveyor system can only perform in accordance with its design specifications when that specific belt is used. It is much better, also cost wise, to specify the upper limit of the resistance indicator as given above that can be met by more than one conveyor belt manufacturer. Figure 3: Indentation rolling resistance indicators for four?different rubbers as a function of temperature. CONCLUSION It is not easy to determine the relationship between the belt speed and the belt's energy consumption. This is partly because the calculation of the indentation rolling, which forms the largest part of the rolling resistance, requests detailed knowledge of the visco-elastic properties of the used rubber compound. In addition the (unknown) velocity dependent components of the coulomb friction and seal and viscous drag of the roller bearings play an important role. Also the resistances that occur at transfer stations, in particular due to the acceleration of the bulk solid, play a role especially at high belt speeds. 高速帶式輸送機的設(shè)計 G. Lodewijks, The Netherlands. G. Lodewijks 荷蘭 SUMMARY摘要：This paper discusses aspects of high-speed belt conveyor design.本文論述的是高速帶式輸送機的設(shè)計。The capacity of a belt conveyor is determined by the belt speed given a belt width and troughing angle.帶式輸送機的輸送能力是由帶的寬度和槽角給定的帶的速度決定的。然而皮Belt speed selection however is limited by practical considerations, which are discussed in this paper.帶速度的選擇受限于實際的考慮因素，這是本文將討論的。皮帶速度也影響輸送帶的工作表現(xiàn)，如其能量的消耗和運行的穩(wěn)定性。The belt speed also affects the performance of the conveyor belt, as for example its energy consumption and the stability of it's running behavior. 3 ENERGY CONSUMPTION能源消耗 Clients may request a specification of the energy consumption of a conveyor system, for example quantified in terms of maximum kW-hr/ton/km, to transport the bulk solid material at the design specifications over the projected route.客戶可以要求一個輸送系統(tǒng)能源消耗的詳細說明，例如設(shè)計規(guī)格超過計劃規(guī)格，運輸散裝固體材料就要最大限度的量化條件kw-hr/ton/km。長久陸地系統(tǒng)For long overland systems, the energy consumption is mainly determined by the work done to overcome the indentation rolling resistance [9].，能源消耗主要取決于所做的工作，以克服壓痕滾動阻力。皮帶所受的阻力取決于橡膠帶粘彈性（時間延遲），粘彈性的效應(yīng)掩飾了托輥的壓痕。作For in-plant belt conveyors, work done to overcome side resistances that occur mainly in the loading area also affects the energy consumption.為在廠的帶式輸送機所做的工作是克服沿邊阻力，沿邊阻力主要發(fā)生在負重區(qū)，也影響能源的消耗。Side resistances include the resistance due to friction on the side walls of the chute and resistance that occurs due to acceleration of the material at the loading point.沿邊阻力包括溜槽壁的摩擦產(chǎn)生的阻力和在裝料點物料的加速度產(chǎn)生的阻力。 皮帶輸送機The required drive power of a belt conveyor is determined by the sum of the total frictional resistances and the total material lift.所需的驅(qū)動功率，是由摩擦阻力的總數(shù)和所要提升物料的總和決定的。The frictional resistances include hysteresis losses, which can be considered as viscous (velocity dependent) friction components.這個摩擦阻力包括滯后損耗，它可以被視為粘性（速度而定）摩擦組件。 It does not suffice to look just at the maximum required drive power to evaluate whether or not the energy consumption of a conveyor system is reasonable.它不足以僅從最大所需驅(qū)動功率來評價一個輸送系統(tǒng)的能源消耗是否是合理的。 The best method to compare the energy consumption of different transport systems is to compare their transport efficiencies.比較不同運輸系統(tǒng)的能源消耗，最好的方法是比較它們的運輸效率等。 3.1 TRANSPORT EFFICIENCY1 運輸效率 There are a number of methods to compare transport efficiencies.有許多方法來比較運輸效率。The first and most widely applied method is to compare equivalent friction factors such as the DIN f factor.首先并最廣泛應(yīng)用的方法是比較當量摩擦因素，如按DIN F系數(shù)。利用當量摩擦系數(shù)An advantage of using an equivalent friction factor is that it can also be determined for an empty belt.的優(yōu)點是，它也可以由一個空皮帶確定。采用當量摩擦系數(shù)的缺點是，它不是一個‘純'效率數(shù)字。It takes into account the mass of the belt, reduced mass of the rollers and the mass of the transported material.考慮到皮帶的大量化，就要減少了托輥的數(shù)量和運送物資的數(shù)量。In a pure efficiency number, only the mass of the transported material is taken into account.純粹的效率高低，僅有材料的運送量，是在考慮之列。 The second method is to compare transportation cost, either in kW-hr/ton/km or in $/ton/km.第二種方法是比較運輸成本，要么kw-hr/ton/km要么$/ton/km。The advantage of using the transportation cost is that this number is widely used for management purposes.比較運輸成本的優(yōu)點在于輸送成本廣泛用于管理策劃。The disadvantage of using the transportation cost is that it does not directly reflect the efficiency of a system.采用運輸成本的不利之處是，它沒有直接地反映著一個體系的效率。 The third and most "pure" method is to compare the loss factor of transport [10].第三種且最“純粹的”方法是比較運輸損耗因子。運輸The loss factor of transport is the ratio between the drive power required to overcome frictional losses (neglecting drive efficiency and power loss/gain required to raise/lower the bulk material) and the transport work.損耗因子是驅(qū)動電源必須克服的摩擦損失（忽略傳動效率和功率損耗/增益須提高/降低大宗材料）和運輸工作兩者的比例。The transport work is defined as the multiplication of the total transported quantity of bulk material and the average transport velocity.運輸工作是被定義為原料的總運輸量和平均運輸速度的乘積。采用運輸損耗因子的The advantage of using loss factors of transport is that they can be compared to loss factors of transport of other means of transport, like trucks and trains.好處是它們能與其他運輸方式的損失因子作比較，如卡車和火車。The disadvantage is that the loss factor of transport depends on the transported quantity of material, which implies that it can not be determined for an empty belt conveyor.缺點是運輸損耗因子依賴于材料的運輸量，這意味著它不能被一個空載的帶式輸送機決定。 3.2 INDENTATION ROLLING RESISTANCE2 壓痕滾動阻力 For long overland systems, the energy consumption is mainly determined by the work done to overcome the indentation rolling resistance.長期陸路系統(tǒng)，能源消耗主要取決于所做的工作，以克服壓痕滾動阻力。 Idler rolls are made of a relatively hard material like steel or aluminum whereas conveyor belt covers are made of much softer materials like rubber or PVC.托輥是由比較硬質(zhì)的材料制成，如鋼或鋁，而輸送帶由許多柔軟材料做成，如橡膠或PVC 。The rolls therefore indent the belt's bottom-cover when the belt moves over the idler rolls, due to the weight of the belt and bulk material on the belt.因此當皮帶在托輥上運動時，輥子就縮進在皮帶的下面，這取決于在皮帶上的皮帶和散裝物料的重量。皮帶下層的壓縮部分的The recovery of the compressed parts of the belt's bottom cover will take some time due to its visco-elastic (time dependent) properties.回彈，將需要一些時間，由于其粘彈性（時間依賴性）的性能。皮帶下層彈復(fù)The time delay in the recovery of the belt's bottom cover results in an asymmetrical stress distribution between the belt and the rolls, see Figure 2.時間的延遲導(dǎo)致了帶和托輥間應(yīng)力的不對稱分布，見圖1 。This yields a resultant resistance force called the indentation rolling resistance force.這個產(chǎn)生抵抗的力量稱為壓痕滾動阻力。The magnitude of this force depends on the visco-elastic properties of the cover material, the radius of the idler roll, the vertical force due to the weight of the belt and the bulk solid material, and the radius of curvature of the belt in curves in the vertical plane.這股力量的大小，依賴于皮帶下層材料的粘彈性性能、托輥的半徑和壓力，壓力取決于皮帶和散裝固體物質(zhì)的重量，以及在垂直面內(nèi)變形部分的曲率半徑。 Figure 2: Asymmetric stress distribution between belt and roll [7].圖1 皮帶和輥之間的不對稱應(yīng)力分布 It is important to know how the indentation rolling resistance depends on the belt velocity to enable selection of a proper belt vel重要的是要知道壓痕滾動阻力是如何取決于皮帶速度，以便選擇一個適當?shù)膸佟? Firstly, the indentation rolling resistance depends on the vertical load on the belt, which is the sum of the belt and the bulk material weight.首先，壓痕滾動阻力取決于皮帶上的垂直載荷，這個載荷是由帶和散裝材料的重量的總和產(chǎn)生的。 If the vertical load on the belt decreases with a factor 2 then the indentation rolling resistance decreases with a factor 2.52 (2 ^4/3).如果垂直載荷對帶減少一個因子2 ，壓痕滾動阻力就減小一個因子2.52（ 2 ^ 4 / 3 ）。假設(shè)恒容量，The bulk load decreases with increasing belt speed assuming a constant capacity.部分負荷減少于帶速的增加。 Therefore, the indentation rolling resistance decreases more than proportionally with increasing belt speed.因此，壓痕滾動阻力減少的比例比帶速的增加要多。 Secondly, the indentation rolling resistance depends on the size of the idler rolls.其次，壓痕滾動阻力取決于托輥的尺寸。 If the roll diameter increases with a factor 2 then the indentation rolling resistance decreases with a factor 1.58 (2 ^2/3).如果托輥直徑增大的一個因子2，壓痕滾動阻力就減小的一個因子1.58 （ 2 ^ 2 / 3 ）。In general the idler roll diameter increases with increasing belt speed to limit the bearing rpm's to maintain acceptable idler life.一般托輥直徑隨帶速的增大而增大，以限制軸承的轉(zhuǎn)速，保持可接受的托輥壽命。 In that case the indentation rolling resistance decreases with increasing belt speed.在此情況下，壓痕滾動阻力隨帶速的增加而減小。 Thirdly, the indentation rolling resistance depends on the visco-elastic properties of the belt's cover material.第三，壓痕滾動阻力取決于皮帶覆蓋材料的粘彈性性能。 These properties depend on the deformation rate, see Figure 3.這些性能在很大程度上依賴于變形速度，見圖2 。皮帶往復(fù)運行的The deformation rate in its turn depends on the size of the deformation area in the belt's bottom cover (depending on belt and bulk load) and on the belt speed.變形速度又取決于在皮帶下層（取決于皮帶及散裝負載）變形區(qū)的規(guī)模和皮帶速度。In general the indentation rolling resistance increases with increasing deformation rate (and thus belt speed), but only to a relatively small account.一般壓痕滾動阻力隨變形速度（因而帶速）的增加而增加， 但相對來說僅僅是一小部分。 Figure 3: Loss factor (tanb) of typical cover rubber [7]圖2 典型橡膠層的損耗因子 Fourthly, the indentation rolling resistance depends on the belt's bottom cover thickness.第四，壓痕滾動阻力取決于皮帶下層的厚度。 If the bottom cover thickness increases with a factor 2 then the indentation rolling resistance increases with a factor 1.26 (2 ^1/3).如果下層厚度增大一個因子2，則壓痕滾動阻力就增大一個因子1.26（ 2 ^ 1 / 3 ）。if a bottom cover is increased to account for an increase in belt wear with increasing belt speed, then the indentation rolling resistance increases as well.如果皮帶下層寬度的增加并提高輸送速度，則壓痕滾動阻力也會有所增加。 It should be realized that the indentation rolling resistance, although important, is not the only velocity dependent resistance.應(yīng)當看到，壓痕滾動阻力雖然重要但不是速度唯一取決于的阻力。 就托輥的The rolling resistance of the idler rolls for example depends on the vertical load as well as on their rotational speed.滾動阻力舉例來說，滾動阻力取決于豎向荷載以及其轉(zhuǎn)速。The effect of the vertical load, which directly depends on the belt speed, is large.垂直載荷的影響直接取決于皮帶速度，影響是大的。 相比之下，The effect of the rotational speed is much smaller.轉(zhuǎn)速的影響是小多了。 Another resistance occurs due to acceleration of the bulk solid material at the loading point.另一阻力是在裝載處由于散裝固體物質(zhì)下落產(chǎn)生的加速度產(chǎn)生的。假定該散裝物料直線落在皮帶上，This resistance increases quadratically with an increase in belt speed assuming that the bulk material falls straight onto the belt.這種阻力的增加是帶速增加的二次方。This will affect smaller, in plant belt conveyors in particular.這影響也是較小的，尤其是輸送木板類的帶式輸送機。 3.3 RUBBER COMPOUNDS3 橡膠化合物 作為之前部分的討論，The indentation rolling resistance depends on the visco-elastic properties of the belt's bottom cover as discussed in the preceding section.壓痕滾動阻力取決于皮帶下層的粘彈性性能。 This implies that the rolling resistance can be decreased by selecting a special low indentation rolling resistance (rubber) compound that is available on the market today.這意味著通過選擇一個特殊壓痕低滾動阻力（橡膠）化合物，滾動阻力可減小，這種橡膠化合物在當今市場上是可用的。A small premium has to be paid for this special compound, but costs can be limited by applying it for the bottom cover only and using a normal wear-resistant compound for the carrying top cover.一個小的補價必須支付這一個特殊化合物，但成本可能被限制，如僅僅申請它為皮帶下層或用一個正常耐磨材料復(fù)合成運載皮帶的上層。 In that case turnovers are required to fully use the energy saving function of the bottom compound.在這種情況下，要求充分地使用底部化合物的節(jié)能作用。 壓痕滾動阻力A Quantitative indication of the level of indentation rolling resistance is the indentation rolling resistance indicator tan/E ^1/3, where tan is