外文翻譯--免耕播種機(jī)鋸切防堵裝置設(shè)計(jì)及其切割機(jī)理的研究

1、<p><b>　　附錄</b></p><p>　　Design of sawing anti-blocking mechanism for</p><p>　　no-tillage planter and its cutting mechanism</p><p>　　Liao Qingxi1,Gao Huanwen2,Shu C

2、aixia1</p><p>　　Abstract: Based on blocking issues of no-tillage planter for dry-land farming in two-crop-a-year region in North of China and shortcomings of anti-blocking mechanism developed, such as higher

3、 rotation speed (above 1500 r/min) and bigger power consumption (width power consumption per unit up to 16～41.74 kW/m, including traction power), a new sawing anti-blocking mechanism was developed and its cutting mechani

4、sm was investigated in this paper. Meanwhile stress distribution of the saw-tooth blade c</p><p>　　Key words: no-tillage planter; sawing anti-blocking mechanism; cutting mechanism; cutting rate</p>&l

5、t;p>　　1　Introduction</p><p>　　Anti-blocking issue of no-tillage planter had become one of the key factors affecting production efficiency and seeding quality of two-crop-a-year region in North of China. I

6、t was because there was a great deal of crop stubbles and crop seeding was started shortly after crop had been harvested, leaving no time for crop stubbles to decay. At present, there are two methods to solve anti-blocki

7、ng issue of no-tillage: 1) Straws were chopped by the straw chopper before seeding, it would lead to addin</p><p>　　It was reported that the blade base linear velocity of several main straw chopping mechanis

8、ms was between 37～56 m/s[2], mostly chopping mechanism combined with cutting and striking had higher striking velocity and higher power consumption[3], e.g. the blade base linear velocity up to 34 m/s could obtain fine c

9、utting effect for corn straws[4], and 24 m/s on rice and wheat straws by supporting pole, respectively[5]. Even if corn straws were cut by sliding cut with vertical blade, its velocity of c</p><p>　　Based on

10、 practical problems, the objective in this paper is to find a way to solve the shortcoming that it 64 is difficult for common smooth blade to seize straws and it must run at higher rotation speed, decrease power consumpt

11、ion and improve cutting effect as well as anti-blocking performance of no-tillage planter. Additionally some experiments were done by selecting saw-tooth as cutting blade of no-tillage planter and cutting mechanism of th

12、e sawing anti-blocking mechanism was investigated.</p><p>　　2　Structure and cutting rule of the sawing anti-blocking mechanism</p><p>　　2.1　Structure and characteristics</p><p>　　Th

13、e sawing anti-blocking mechanism was made up of saw-tooth blade, throwing ban device, principal shaft, moved and fixed blade combination, covering shell, opener and working frame as well as transmission system. Sketch of

14、 the sawing anti-blocking mechanism is shown in Fig. 1. The main parts included saw-tooth blade, throwing ban device as well as fixed blade combinations. Diameter of saw-tooth with 60 teeth was 350 mm; throwing ban devic

15、e with max 270 mm turning diameter was fixed on between ad</p><p>　　2.2　Cutting principle</p><p>　　The sawing anti-blocking mechanism was driven to reverse rotation by power. First, straws were

16、cut in no-sustaining mode by saw-tooth blades while saw-tooth blades touched straws, then after straws were completely cut down, they would be free and be thrown to the rear of opener by throwing ban device and inertial

17、force. Second, straws not being completely cut down would be thrown to former upward and be cut in sustaining mode by fixed blade combinations until any of straws would be cut down, st</p><p>　　Working proc

18、edures of the sawing anti-blocking mechanism were as follows: 1) no-sustaining cut phase: static straws relative to ground were cut firstly atNpoint by saw-tooth blades, then, straws would be cut down completely or embed

19、ded in saw-tooth. Straws being cut down completely would be free and 65　Liao Qingxi et al: Design of anti-blocking mechanism for no-tillage planter dropped into adjacent saw-tooth; 2) dragging and delivering phase: afte

20、r straws dropped into adjacent saw-tooth, they w</p><p>　　4)throwing phase: straws being cut down were thrown directly to the rear of opener by tooth former slanting angle of the saw-tooth and throwing ban d

21、evice, time and again, straws would be carried out continuously to cut and throw. The working principle of the sawing anti-blocking mechanism is shown in Fig.2.</p><p>　　2.3　Analysis of mechanics characteris

22、tics of saw-tooth blade </p><p>　　Cutting properties of saw-tooth to cut straws belong to wriggly cut of no-metal materials, its ultimate objective is not only to improve surface cutting quality, but also to

23、 raise cutting efficiency, so it can decrease sawing force and power consumption[9]. Because the ratio of its diameter 350 mm to its thickness 1.8 mm is over 150, the saw-tooth blade belongs to exceed thin disc. It is as

24、 plane stress and no-axis symmetry problem according to elasticity theory. And because the saw-tooth blade </p><p>　　The stress distribution of the saw-tooth blade was calculated by the ANASYS finity element

25、 software. Number of the tooth participating in cutting straws was determined to 2～3 teeth while diameter of straws was in 20～45 mm[11]. The saw-tooth made in 65Mn ofEequal to 210 GPa[12]andμto 0.28 was separated into 12

26、00 cells and 1260 nodes by trapezia gridding. Thus the stress distributions ofX,YandXYplane had been obtained by the ANASYS software according to the most average wring value 26.8 Nm[13]of t</p><p>　　3　Resul

27、ts and discussion</p><p>　　3.1　Experiments and analysis of rotation direction of the saw-tooth blade for cutting quality</p><p>　　Some experiments were done by clockwise and counter-clockwise ro

28、tation of the saw-tooth blade in the soil bin device. The results are listed in Table 1. </p><p>　　Table 1　Experimental results of rotation direction of the saw-tooth blade</p><p>　　Table 1 show

29、ed that the way of cutting straws at counter-clockwise rotation would be of benefit to improve cutting quality and throwing effect, and boost up adaptability of weight of different stubble mulch. Therefore, counter-clock

30、wise rotation direction of the saw-tooth blade had been determined.</p><p>　　3.2　Effect of the rotation speed on cutting quality</p><p>　　The experiments were done by selecting velocity 0.3 m/s

31、of vehicle and interval 5 mm of the moved and fixed blade, and spacing 20 mm between the saw-tooth and ground as well as weight 11250 kg/hm2of the straws mulch, experimental results are shown in Fig.4. The results indica

32、ted that the power consump-tion and cutting rate would increase with rising of rotation speed of the saw-tooth blade. Because the wring values of cutting straws were equal basically on the same working condition, the cut

33、ting</p><p>　　Fig.4　Relationships among rotation speed, cutting rate and power consumption</p><p>　　3.3　Effect of the straw moisture on cutting quality</p><p>　　The straw moisture o

34、f the same crops is different for different autumn and reaping time. The moisture were 20%, 40.5%, 64.4% and 80.16% respectively, after corn straws had been placed in field for different periods. Experiments were done by

35、 selecting velocity 0.3 m/s of vehicle and interval 5 mm between the moved and fixed blade and spacing 20 mm between sawtooth and ground, and rotation speed 650 r/min as well as mass 11250 kg/hm2of straws mulch, the resu

36、lts were shown in Fig.5. Fig.5　Results o</p><p>　　Experimental results show that power consumption decreased with increasing of straw moisture and cutting rate of straws increased with increasing of straws m

37、oisture on the same working condition, which had connected importantly with different moisture of straws. Straws would take on bigger hardness and best firmness and fine brittleness when straws moisture was in higher, wh

38、ich demonstrated that it had been easy to finish to cut straws. But straws would take on tired and soft status for fine fle</p><p>　　tearing while straw moisture was up to 20%(Fig.7). </p><p>　

39、　4　Conclusions</p><p>　　1) A new type of sawing anti-blocking mechanism, which could get rid of some shortcoming that common smooth blade is difficult to seize straws as well as high rotation speed, was desi

40、gned according to the anti-blocking requirements of no-tillage planter and need in practice. The sawing anti-blocking mechanism had strong capability to seize straws and lower rotation (650 r/min) speed and lower consump

41、tion (power consumption per unit width up to 2.95 kW/m) and higher cutting rate of straws, a new </p><p>　　2) The stress distribution of the saw-tooth blade was calculated by the ANASYS finity element softwa

42、re. The results showed that its intension would be difficult to be destroyed and the sawtooth blade was feasible to cut corn straws.</p><p>　　3) The sawing anti-blocking mechanism realized an integrated func

43、tion of directly throwing and cutting straws by counter-clockwise. The straws could be cut down completely by two cutting modes of sustaining and no-sustaining cut. Meanwhile, the straws being cut down completely could b

44、e directly thrown to the rear of opener by the former tooth horn of sawtooth blade and throwing ban device.</p><p>　　4) Experimental results showed in the soil bin device that: (1) Cutting rate of straws inc

45、reased with increasing of rotation speed of saw-tooth blade and moisture of straws, and higher moisture of straws would be of benefit to improve cutting quality; (2) Power consumption increases along with increasing of r

46、otation speed, and that decreased with increasing of moisture of straws; ( 3 ) Cutting rate of straws decreased with increasing of velocity of the vehicle while interval between the fixed an</p><p>　　Compare

47、d with the other driving anti-blocking mechanism, the theoretical analysis and experimental results showed that the sawing anti-blocking mechanism had better capability to cut and lower rotate speed and power consumption

48、 as well as stronger suitability for different stubbles mulch. </p><p>　　免耕播種機(jī)鋸切防堵裝置設(shè)計(jì)及其切割機(jī)理的研究</p><p>　　摘要:針對(duì)我國(guó)北方旱地一年兩熟地區(qū)免耕播種機(jī)堵塞現(xiàn)象和已有卞動(dòng)式防堵裝置轉(zhuǎn)速高( 1500 r/ min以上)、功耗大 (單位幅寬達(dá)1641.74 kW/m，含牽引功率)的現(xiàn)實(shí)問(wèn)

49、題，設(shè)計(jì)了一種新型免耕播種機(jī)鋸切防堵裝置，分析了該裝置的切割機(jī)理，應(yīng)用有限元ANSYS軟件計(jì)算了鋸齒圓盤(pán)切刀的應(yīng)力分布，得出了鋸齒圓盤(pán)切刀川于玉米秸稈切割的可行性。上述試驗(yàn)表明:1)該裝置采用逆轉(zhuǎn)式作業(yè)，兼有無(wú)支撐和有支撐兩種切割方式，切割徹底，并能借助刀齒前角和拋撒板將已切斷秸稈定向拋送到開(kāi)溝器后方，實(shí)現(xiàn)了切割、定向拋撒一體化功能;2)秸稈切碎率隨轉(zhuǎn)速和秸稈含水率的增大而增大，秸稈含水率高時(shí)有利于提高切割質(zhì)量;3)秸稈切碎率在動(dòng)定刀間

50、隙一定時(shí)，隨前進(jìn)速度增大而降低，小間隙時(shí)無(wú)漏切和撕皮現(xiàn)象，切割質(zhì)量高，功耗小。理論和試驗(yàn)結(jié)果表明:與其他卞動(dòng)式防堵裝置相比，鋸切防堵裝置具有良好的切割性能，其轉(zhuǎn)速低 (650 r/min)、功耗小(單位幅寬為2.95 kW/m)、秸稈覆蓋量適應(yīng)性強(qiáng)，為改善免耕播種機(jī)防堵性能提供了一條新途徑。</p><p>　　關(guān)鍵詞:免耕播種機(jī);鋸切防堵裝置;切割機(jī)理;切碎率</p><p><b

51、>　　1、 說(shuō)明</b></p><p>　　免耕播種機(jī)堵塞問(wèn)題是影響我國(guó)一年兩熟的北方旱地地區(qū)的生產(chǎn)效率和播種質(zhì)量關(guān)鍵因素之一。這是因?yàn)橛写罅康淖魑锔缍以谧魑锸崭畈痪镁鸵M(jìn)行播種，不留時(shí)間使作物根茬腐爛。目前，有兩種方法來(lái)解決免耕播種機(jī)的堵塞問(wèn)題：1）在播種前用秸稈刀切碎秸稈，這將導(dǎo)致增加的工作程序，并增加生產(chǎn)成本，以及推遲播期; 2）茬被安裝在免耕播種機(jī)上的切除機(jī)構(gòu)清除，如在河北農(nóng)哈哈機(jī)

52、械有限公司的紡紗地帶和溝小麥播種機(jī)和中國(guó)產(chǎn)農(nóng)業(yè)大學(xué)[ 1 ]的2BMDF玉米地帶等等。在實(shí)踐中，駕駛砍機(jī)制在防堵問(wèn)題上有巨大作用，但是因?yàn)榻斩捛兴闀r(shí)的高轉(zhuǎn)速，會(huì)產(chǎn)生更大的振動(dòng)和噪聲以及降低安全。</p><p>　　據(jù)報(bào)道，幾個(gè)主要秸稈切碎機(jī)制的刀片基礎(chǔ)線速度是37 ～ 56米/秒[ 2 ] ，其中大部分是砧板機(jī)制結(jié)合切割突出了更高的驚人速度和更高的功率消耗[ 3 ] ，例如：刀片基礎(chǔ)線速度高達(dá)34米/秒能取得削

53、減玉米秸稈的良好效果[ 4 ] ，而大米和小麥秸稈高達(dá)24米/秒 [ 5 ] 。即使玉米秸稈被與與垂直的滑動(dòng)切口相切，其切割一個(gè)和兩三個(gè)秸稈的速度必須上升到10.3米/秒， 13.6米/秒， 15.8米/秒[ 6 ] ，并且有較高的功率消耗。簡(jiǎn)言之,因?yàn)轳{駛砍機(jī)制目前開(kāi)發(fā)有高旋轉(zhuǎn)速度(上面 1500轉(zhuǎn)/分 )并且更高的力量消費(fèi)(寬度單位能耗高達(dá)16 ? 41.74千瓦/米，包括牽引動(dòng)力),在實(shí)踐中以減少旋轉(zhuǎn)速度和力量消費(fèi)將是迫切的.&l

54、t;/p><p>　　根據(jù)實(shí)際問(wèn)題，本文件中的目標(biāo)是要找到一種辦法來(lái)解決64個(gè)缺陷，制造出對(duì)抓住稻草并且它必須在更高的旋轉(zhuǎn)速度下，減少能耗和提高切割效果以及防堵性能免耕播種機(jī)。另外一些實(shí)驗(yàn)，對(duì)選擇了齒形切削刀片的免耕播種機(jī)和切削機(jī)理的鋸切防堵機(jī)制進(jìn)行了研究。</p><p>　　2結(jié)構(gòu)和規(guī)則的鋸切防堵裝置的切割原理</p><p><b>　　2.1結(jié)構(gòu)和特性

55、</b></p><p>　　鋸切防堵裝置由鋸齒圓盤(pán)切刀、定刀組合、拋撒板、主軸、罩殼、機(jī)架、以及傳動(dòng)系統(tǒng)組成。鋸切防堵裝置的零件圖如圖1.其中鋸齒圓盤(pán)切刀、拋撒板、和定刀組合是該裝置的主要組成部分。設(shè)計(jì)的鋸齒圓盤(pán)直徑為350 mm,60齒;拋撒板安裝在相鄰兩鋸齒圓盤(pán)間,其最大回轉(zhuǎn)直徑為270 mm;定刀組合由鋸齒形定刀和直刀形定刀組合而成,鋸齒形定刀與鋸齒圓盤(pán)切刀配合對(duì)秸稈進(jìn)行剪切,而直刀形定刀主要

56、起阻擋未切斷秸稈落入拋撒區(qū)的作用,同時(shí)也參與剪切。該裝置安裝在土槽試驗(yàn)臺(tái)上,工作幅寬為600 mm，相鄰間隔為200毫米。其工作特點(diǎn)是秸稈既可由鋸齒切刀直接切碎,也可由鋸齒切刀和定刀組合作用而切碎,兼有無(wú)支撐與有支撐2種切割方式,鋸齒刀端線速度低于甩刀式切割器線速度,即具有將高速砍切變?yōu)榈退黉徢械奶攸c(diǎn)。</p><p>　　開(kāi)溝鏟組合; 2.鋸齒圓盤(pán)切刀; 3.秸稈導(dǎo)向板; 4.定刀組合; 5.主軸; 6.拋散弧

57、板；</p><p>　　7.罩殼; 8.機(jī)架; 9.軸承座; 10.傳感器; 11.電纜; 12.調(diào)速電機(jī); 13.臺(tái)車懸掛臂</p><p>　　圖1　鋸齒防堵裝置結(jié)構(gòu)示意圖</p><p><b>　　2.2切割原理</b></p><p>　　鋸齒圓盤(pán)切刀由動(dòng)力驅(qū)動(dòng)作逆時(shí)針旋轉(zhuǎn)。首先，當(dāng)鋸齒底部與秸稈接觸時(shí)

58、,鋸齒嵌住秸稈進(jìn)行無(wú)支撐切割,已切斷的秸稈,依靠鋸齒圓盤(pán)切刀的刀齒和拋撒板的旋轉(zhuǎn)作用向后拋送。其次，未完全切斷的秸桿在刀齒作用下,向前上方運(yùn)動(dòng)與定刀組合發(fā)生剪切作用,秸稈進(jìn)行有支撐切割,從而完成秸稈的全部切斷,由鋸齒切刀和拋散板將斷稈拋送到開(kāi)溝器后方。如此反復(fù),實(shí)現(xiàn)秸桿的連續(xù)切割和拋送。工作時(shí)圓盤(pán)鋸齒不入土,其旋轉(zhuǎn)最低點(diǎn)離地15~30 mm。就田間垂直存在的秸稈的散布情況或某個(gè)角度的前進(jìn)方向而言，鋸切防堵裝置的橫向的鋸齒是為了減少重復(fù)切

59、割、漏割和撕裂稻谷。</p><p>　　鋸切防堵裝置的工作程序制如下：1）無(wú)支撐切割階段：相對(duì)地面靜止的稻草首先被鋸齒片切割，然后秸稈被完全切除或牢牢嵌入鋸齒中。已切斷的秸稈做自由運(yùn)動(dòng)并落到鄰近的鋸齒上; 2 )拖拽交付階段:在稻草落下了相鄰近的鋸牙齒以后，他們將被拋灑裝置向上扔到前者,而且，被嵌入鋸牙齒的稻草將被更高的速度旋轉(zhuǎn)的鋸牙齒向前拋出; 3 )支撐切階段:在無(wú)支撐階段未被切割的稻草被定刀組合切割直到被

60、完全切割。4 )拋撒階段:正在被切割的稻草直接被鋸齒圓盤(pán)切刀和拋散弧板扔到開(kāi)溝器的后面,再一次,稻草將被連續(xù)地切割和拋撒。鋸切防堵裝置的工作的原理如圖2所示</p><p>　　1.待切秸稈; 2.定刀組合; 3.罩殼; 4.鋸齒圓盤(pán)切刀; 5.拋撒板;</p><p>　　6.開(kāi)溝器; 7.斷稈; 8.地表; 9.放大定刀組合; 10.鋸齒型定刀;<

61、/p><p>　　N為無(wú)支撐切割點(diǎn);K為支撐切割點(diǎn);M為研究對(duì)象</p><p>　　圖2　鋸齒防堵裝置防堵原理示意圖</p><p>　　2.3鋸齒圓盤(pán)切刀的力學(xué)性能</p><p>　　切割秸稈的鋸齒圓盤(pán)切刀的切割特性屬于無(wú)金屬材料蠕動(dòng)切割,它的最終的目的是不僅提供切割表面的質(zhì)量,而且提高切碎效率，因此它能減少切削力和能量的消耗[ 9 ].因

62、為它350毫米的直徑與它1.8毫米的厚度的比值超過(guò)了150 ,鋸齒圓盤(pán)切刀屬于超過(guò)薄圓盤(pán)。它是根據(jù)彈性理論的水平壓力和無(wú)軸對(duì)稱問(wèn)題。并且因?yàn)殇忼X圓盤(pán)切刀是，由凸緣托盤(pán)緊縮,它的中心洞的6個(gè)自由被限制,因此它的中心部件被認(rèn)作完全約束而沒(méi)有任何旋轉(zhuǎn)和移動(dòng)。.鋸齒圓盤(pán)切刀屬于過(guò)度的切刀工具,在秸稈切割中它使其達(dá)到非傳統(tǒng)的切割力，主要原因如下：1 )內(nèi)空并且外硬的稻草結(jié)構(gòu)決定了微硬部分的差異分布,因此單個(gè)鋸齒的力在切稻草時(shí)是不明確的; 2 )

63、因?yàn)殇忼X圓盤(pán)切刀的鋸齒不連續(xù)所以鋸齒圓盤(pán)切刀的全部的切削力在水平方向?qū)⒉淮_定。這些選擇特征將使鋸齒圓盤(pán)切刀變得更理想，而且這些理想特性大小要與外部承受載荷上的承載特性和鋸齒圓盤(pán)切刀尺寸相比較。因此為保證切割的平穩(wěn)需弄清鋸齒圓盤(pán)切刀所受的力。</p><p>　　圖3 鋸齒圓盤(pán)切刀的壓力分布</p><p>　　鋸齒圓盤(pán)切刀的壓力分布由有限元ANSYS軟件計(jì)算評(píng)估。當(dāng)秸稈直徑在20~45毫

64、米時(shí)參與切割秸稈的齒數(shù)一般為2~3個(gè)[11].由E等于210Gpa[12] 、μ為0.28的25Mn制成的鋸齒圓盤(pán)切刀被分成1200隔間和1260個(gè)小節(jié)。這樣ANASYS 軟件根據(jù)鋸齒圓盤(pán)切刀切割秸稈26.8牛米的最平均扭矩 [ 13 ]的擰傳感器就獲得了X,Y和XY平面的力的分布，計(jì)算結(jié)果如下：1）看到鋸齒圓盤(pán)切刀曾擔(dān)任替代從整體應(yīng)力分布的鋸齒波，牙齒和周圍中心孔的鋸齒波已分發(fā)給主應(yīng)力，最大壓應(yīng)力達(dá)70776帕，此外，最大的拉應(yīng)力高達(dá)

65、19945帕。與鋸齒圓盤(pán)切刀735兆帕產(chǎn)量疲勞內(nèi)涵[ 12 ]相比，該鋸齒圓盤(pán)切刀很難被摧毀，因此削減玉米秸稈是可行的; 2 ）圖3顯示，鋸齒圓盤(pán)切刀的應(yīng)力是對(duì)稱分布的，相對(duì)更壓力的區(qū)域只占整體的3.33 ％，其他占96.67 ％；3 ）在前齒首先接觸秸稈時(shí)，鋸齒圓盤(pán)切刀的前牙的承受最大的力，其應(yīng)力值在切削秸稈前最小，可是當(dāng)開(kāi)始切斷秸稈時(shí)，應(yīng)力值將大幅增加，其值將比剛切割時(shí)大倍。在完成切割秸稈時(shí)壓力將降到最低點(diǎn)。因此，鋸齒圓盤(pán)切刀將承擔(dān)

66、交變應(yīng)力。</p><p><b>　　3結(jié)果與討論</b></p><p>　　3.1實(shí)驗(yàn)和鋸齒圓盤(pán)切刀旋轉(zhuǎn)方向的切割質(zhì)量分析</p><p>　　有些實(shí)驗(yàn)是鋸齒圓盤(pán)切刀在土壤裝置中做順時(shí)針和逆時(shí)針旋轉(zhuǎn)的。結(jié)果列于表1 。</p><p>　　表1鋸齒圓盤(pán)切刀旋轉(zhuǎn)方向的實(shí)驗(yàn)結(jié)果</p><p>

67、　　表1顯示，在逆時(shí)針旋轉(zhuǎn)時(shí)的切割方式將有利于提高切割質(zhì)量和拋撒效果，能增強(qiáng)不同的覆蓋率。因此，經(jīng)常選擇逆時(shí)針旋轉(zhuǎn)的鋸齒圓盤(pán)切刀。</p><p>　　3.2 旋轉(zhuǎn)速度對(duì)切割質(zhì)量的影響</p><p>　　實(shí)驗(yàn)所選擇的是速度為0.3米/ s的車輛和間隔為5毫米的移動(dòng)和固定刀片，并且鋸齒圓盤(pán)切刀與地面間隔為20毫米以及11250 kg/hm2的秸稈覆蓋，實(shí)驗(yàn)結(jié)果圖4所示。結(jié)果表明，電力消費(fèi)

68、和切割率會(huì)增隨鋸齒圓盤(pán)切刀轉(zhuǎn)速的增加而增大。由于切割秸稈時(shí)的扭矩在基本上相同的工作條件下是相同的，在鋸齒圓盤(pán)切刀的轉(zhuǎn)速高于650轉(zhuǎn)/分時(shí)切割率可高達(dá)100 ％ 。這是因?yàn)殡S著防堵免耕播種機(jī)轉(zhuǎn)速的增加秸稈切割率會(huì)提高，這是是肯定的。</p><p>　　3.3秸稈濕度對(duì)切割質(zhì)量的影響</p><p>　　同樣莊稼的秸稈濕度在不同的秋季和不同的收割時(shí)間是不同的。在玉米秸稈被放置在不同區(qū)域的地里

69、后，它的濕度分別為20%, 40.5%, 64.4% 和80.16%。在選擇0.3米/秒的牽引速度、動(dòng)刀定刀5毫米的間隔、切刀和地面相距20毫米和650轉(zhuǎn)/分、11250千克/百米^2的覆蓋率的條件下進(jìn)行試驗(yàn)，結(jié)果如圖5.</p><p>　　實(shí)驗(yàn)結(jié)果顯示，在同等工作條件下隨著秸稈濕度的增加能量消耗減少切碎率增加，這些都與不同的秸稈濕度緊密相關(guān)。當(dāng)秸稈濕度更高時(shí)，秸稈會(huì)有更大的硬度和最強(qiáng)的堅(jiān)實(shí)度還有良好的脆性，這

70、表明此時(shí)很容易削減秸稈。秸稈含水量低較低時(shí)，秸稈的彈性和韌性較好，所以很容易撕皮和堵塞。鋸齒圓盤(pán)切刀在秸稈含水率高達(dá)80.16 ％時(shí)具有良好的切割質(zhì)量和更高的切碎率。然而，在秸稈含水量達(dá)20 ％時(shí)，會(huì)產(chǎn)生撕皮現(xiàn)象。</p><p><b>　　秸稈濕度/%</b></p><p>　　能量消耗 切碎</p><p>　　圖5 秸稈