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Link mechanism
Linkages include garage door mechanisms, car wiper mechanisms, gear shift mechanisms.??They are a very important part of mechanical engineering which is given very little attention...
A link is defined as a rigid body having two or more pairing elements which connect it to other bodies for the purpose of transmitting force or motion . ??In every machine, at least one link either occupies a fixed position relative to the earth or carries the machine as a whole along with it during motion. ?? This link is the frame of the machine and is called the fixed link.
An arrangement based on components connected by rotary or sliding interfaces only is called a linkage.?? These type of connections, revolute and prismatic, are called lower pairs. Higher pairs are based on point line or curve interfaces.
Examples of lower pairs include hinges rotary bearings, slideways , universal couplings. Examples of higher pairs include cams and gears.
Kinematic analysis, a particular given mechanism is investigated based on the mechanism geometry plus factors which identify the motion such as input angular velocity, angular acceleration, etc.?? Kinematic synthesis is the process of designing a mechanism to accomplish a desired task.?? Here, both choosing the types as well as the dimensions of the new mechanism can be part of kinematic synthesis.
Planar, Spatial and Spherical Mechanisms
A planar mechanism is one in which all particles describe plane curves is space and all of the planes are co-planar..??The majority of linkages and mechanisms are designed as planer systems. The main reason for this is that planar systems are more convenient to engineer.?? Spatial mechanisma are far more complicated to engineer requiring computer synthesis. ??Planar mechanisms ultilising only lower pairs are called planar linkages. Planar linkages only involve the use of revolute and prismatic pairs
A spatial mechanism has no restrictions on the relative movement of the particles. Planar and spherical mechanisms are sub-sets of spatial mechanisms..Spatial mechanisms / linkages are not considered on this page
Spherical mechanisms has one point on each linkage which is stationary and the stationary point of all the links is at the same location. ??The motions of all of the particles in the mechanism are concentric and can be repesented by their shadow on a spherical surface which is centered on the common location..Spherical mechanisms /linkages are not considered on this page
Mobility
An important factor is considering a linkage is the mobility expressed as the number of degrees of freedom.??The mobility of a linkage is the number of input parameters which must be controlled independently in order to bring the device to a set position.??It is possible to determine this from the number of links and the number and types of joints which connect the links...
A free planar link generally has 3 degrees of freedom (x , y, θ ). ?? One link is always fixed so before any joints are attached the number of degrees of freedom of a linkage assembly with n links = DOF = 3 (n-1)
Connecting two links using a joint which has only on degree of freedom adds two constraints. Connecting two links with a joint which has two degrees of freedom include 1 restraint to the systems. The number of 1 DOF joints = say j 1 and the number of joints with two degrees of freedom = say j 2.. The Mobility of a system is therefore expressed as mobility = m = 3 (n-1) - 2 j 1 - j 2
Examples linkages showing the mobility are shown below..
A system with a mobility of 0 is a structure. A system with a mobility of 1 can be fixed in position my positioning only one link. A system with a mobility of 2 requires two links to be positioned to fix the linkage position..
This rule is general in nature and there are exceptions but it can provide a very useful initial guide as the the mobility of an arrangement of links...
Grashof's Law
When designing a linkage where the input linkage is continuously rotated e.g. driven by a motor it is important that the input link can freely rotate through complete revolutions.?? The arrangement would not work if the linkage locks at any point.?? For the four bar linkage Grashof's law provides a simple test for this condition
Grashof's law is as follows:
For a planar four bar linkage, the sum of the shortest and longest links cannot be greater than the sum of the remaining links if there is to be continuous relative rotation between two members.
Referring to the 4 inversions of a four bar linkage shown below ..Grashof's law states that one of the links (generally the shortest link) will be able to rotate continuously if the following condition is met...
b (shortest link ) + c(longest link) < a + d
Four Inversions of a typical Four Bar Linkage
Note: If the above condition was not met then only rocking motion would be possible for any link..
Mechanical Advantage of 4 bar linkage
The mechanical advantage of a linkage is the ratio of the output torque exerted by the driven link to the required input torque at the driver link.?? It can be proved that the mechanical advantage is directly proportional to Sin( β ) the angle between the coupler link(c) and the driven link(d), and is inversely proportional to sin( α ) the angle between the driver link (b) and the coupler (c) .??These angles are not constant so it is clear that the mechanical advantage is constantly changing.
The linkage positions shown below with an angle α = 0 o and 180 o has a near infinite mechanical advantage.??These positions are referred to as toggle positions. ??These positions allow the 4 bar linkage to be used a clamping tools.
The angle β is called the "transmission angle".?? As the value sin(transmission angle) becomes small the mechanical advantage of the linkage approaches zero. ?? In these region the linkage is very liable to lock up with very small amounts of friction.??When using four bar linkages to transfer torque it is generally considered prudent to avoid transmission angles below 450 and 500.
In the figure above if link (d) is made the driver the system shown is in a locked position.??The system has no toggle positions and the linkage is a poor design
Freudenstein's Equation
This equation provides a simple algebraic method of determining the position of an output lever knowing the four link lengths and the position of the input lever.??
Consider the 4 -bar linkage chain as shown below..
The position vector of the links are related as follows
l 1 + l 2 + l 3 + l 4 = 0
Equating horizontal distances
l 1 cos θ 1 + l 2 cos θ 2 + l 3 cos θ 3 + l 4 cos θ 4 = 0
Equating Vertical distances
l 1 sin θ 1 + l 2 sin θ 2 + l 3 sin θ 3 + l 4 sin θ 4 = 0
Assuming θ 1 = 1800 then sin θ 1 = 0 and cosθ 1 = -1 Therefore
- l 1 + l 2 cosθ 2 + l 3 cosθ 3 + l 4 cos θ 4 = 0
and .. l 2 sin θ 2 + l 3 sin θ 3 + l 4 sin θ 4 = 0
Moving all terms except those containing l 3 to the RHS and Squaring both sides
l 32 cos 2 θ 3 = (l 1 - l 2 cos θ 2 - l 4 cos θ 4 ) 2
l 32 sin 2 θ 3 = ( - l 2 sin θ 2 - l 4 sin θ 4) 2
Adding the above 2 equations and using the relationships
cos ( θ 2 - θ 4 ) = cos θ 2 cos θ 4 + sin θ 2sin θ 4 ) ?? and ?? sin2θ + cos2θ = 1
the following relationship results..
Freudenstein's Equation results from this relationship as
K 1 cos θ 2 + K2 cos θ 4 + K 3 = cos ( θ 2 - θ 4 )
K1 = l1 / l4 ???? K2 = l 1 / l 2???? K3 = ( l 32 - l 12 - l 22 - l 2 4 ) / 2 l 2 l 4
This equation enables the analytic synthesis of a 4 bar linkage. ?? If three position of the output lever are required corresponding to the angular position of the input lever at three positions then this equation can be used to determine the appropriate lever lengths using three simultaneous equations...
Velocity Vectors for Links
The velocity of one point on a link must be perpendicular to the axis of the link, otherwise there would be a change in length of the link.
On the link shown below B has a velocity of vAB = ω.AB perpendicular to A-B. "? The velocity vector is shown...
Considering the four bar arrangement shown below. The velocity vector diagram is built up as follows:
· As A and D are fixed then the velocity of D relative to A = 0 a and d are located at the same point
· The velocity of B relative to a is vAB = ω.AB perpendicular to A-B. This is drawn to scale as shown
· The velocity of C relative to B is perpedicular to CB and passes through b
· The velocity of C relative to D is perpedicular to CD and passes through d
· The velocity of P is obtained from the vector diagram by using the relationship bp/bc = BP/BC
The velocity vector diagram is easily drawn as shown...
Velocity of sliding Block on Rotating Link
Consider a block B sliding on a link rotating about A. The block is instantaneously located at B' on the link..
The velocity of B' relative to A = ω.AB perpendicular to the line. The velocity of B relative to B' = v. The link block and the associated vector diagram is shown below..
Acceleration Vectors for Links
The acceleration of a point on a link relative to another has two components:
· 1) the centripetal component due to the angular velocity of the link.ω 2.Length
· 2) the tangential component due to the angular acceleration of the link....
· The diagram below shows how to to construct a vector diagram for the acceleration components on a single link.
The centripetal acceleration ab' = ω 2.AB towards the centre of rotation.?? The tangential component b'b = α. AB in a direction perpendicular to the link..
The diagram below shows how to construct an acceleration vector drawing for a four bar linkage.
· For A and D are fixed relative to each other and the relative acceleration = 0 ( a,d are together )
· The acceleration of B relative to A are drawn as for the above link
· The centripetal acceleration of C relative to B = v 2CB and is directed towards B ( bc1 )
· The tangential acceleration of C relative to B is unknown but its direction is known
· The centripetal acceleration of C relative to D = v 2CD and is directed towards d( dc2)
· The tangential acceleration of C relative to D is unknown but its direction is known.
· The intersection of the lines through c1 and c 2 locates c
The location of the acceleration of point p is obtained by proportion bp/bc = BP/BC and the absolute acceleration of P = ap
The diagram below shows how to construct and acceleration vector diagram for a sliding block on a rotating link..
The link with the sliding block is drawn in two positions..at an angle dω
The velocity of the point on the link coincident with B changes from ω.r =a b 1 to ( ω + dω) (r +dr) = a b 2
The change in velocity b1b2has a radial component ωr d θ and a tangential component ωdr + r dω
The velocity of B on the sliding block relative to the coincident point on the link changes from v = a b 3 to v + dv = a b 4.
The change in velocity = b3b4 which has radial components dv and tangential components v d θ
The total change in velocity in the radial direction = dv- ω r d θ
Radial acceleration = dv / dt = ω r d θ / dt = a - ω2 r
The total change in velocity in the tangential direction = v dθ + ω dr + r α
Tangential acceleration = v dθ / dt + ω dr/dt + r d ω / dt
= v ω + ω v + r α = α r + 2 v ω
The acceleration vector diagram for the block is shown below
Note : The term 2 v ω representing the tangential acceleration of the block relative to the coincident point on the link is called the coriolis component and results whenever a block slides along a rotating link and whenever a link slides through a swivelling block
- 9 -
一、課題的目的、意義、國(guó)內(nèi)外現(xiàn)狀及發(fā)展方向
1、目的
該振動(dòng)篩的篩分物料為球磨機(jī)產(chǎn)品。該產(chǎn)品的大小不是很平均,為了做出更符合要求的物料就需要用振動(dòng)篩來(lái)將球磨機(jī)產(chǎn)品進(jìn)一步細(xì)分,將不符合要求的物料從新用球磨機(jī)磨小。經(jīng)過這樣的反復(fù)處理最終將物料全部做成符合要求的產(chǎn)品[1]。
2、意義
礦山機(jī)械產(chǎn)品屬于小批量、多品種、使用面廣的機(jī)械設(shè)備,按用途可分為采掘設(shè)備、提升設(shè)備、礦用車輛、破碎粉磨設(shè)備、篩分設(shè)備、洗選設(shè)備及焙燒設(shè)備等七大類[2] 。礦山機(jī)械為重機(jī)裝備,是為基礎(chǔ)原材料工業(yè)服務(wù)的,是我國(guó)機(jī)械工業(yè)中的一個(gè)重要分支。長(zhǎng)期以來(lái),礦山機(jī)械在開發(fā)我國(guó)礦業(yè)資源、促進(jìn)礦業(yè)經(jīng)濟(jì)發(fā)展、實(shí)現(xiàn)礦山生產(chǎn)現(xiàn)代化的進(jìn)程中起著十分重要、不可替代的支撐作用。而礦業(yè)資源的開發(fā)、利用主要是通過礦山機(jī)械來(lái)實(shí)現(xiàn)、完成的。因此,礦山機(jī)械的先進(jìn)性與現(xiàn)代化,在一定程度上反映了一個(gè)國(guó)家的工業(yè)化水平??梢?,礦山機(jī)械對(duì)于國(guó)民經(jīng)濟(jì)的發(fā)展有著特別重要的地位和作用[3] 。篩分設(shè)備在礦山機(jī)械中占有重要地位,它的發(fā)展不僅僅代表著中國(guó)礦山機(jī)械的發(fā)展,它還代表著中國(guó)國(guó)力的增強(qiáng),著一個(gè)國(guó)家的基礎(chǔ)工業(yè)的實(shí)力和工業(yè)科技水平[4]。
3、國(guó)內(nèi)外現(xiàn)狀
目前國(guó)內(nèi)篩機(jī)產(chǎn)品種類有圓振動(dòng)篩、直線振動(dòng)篩、橢圓振動(dòng)篩、高頻振動(dòng)篩、弧形篩、等厚篩、概率篩、冷礦篩、熱礦篩、節(jié)肢篩等,旋振篩和各種振動(dòng)給料機(jī)械,多達(dá)50多個(gè)系列近1000種規(guī)格,產(chǎn)品已在冶金、礦山、煤炭、輕工等許多行業(yè)得到廣泛的應(yīng)用,基本上滿足了國(guó)內(nèi)國(guó)民經(jīng)濟(jì)建設(shè)的需要[5]。據(jù)2002年行業(yè)調(diào)查了解,全國(guó)篩分機(jī)械制造企業(yè)已多達(dá)300余家,從所有制來(lái)看,除國(guó)營(yíng)、集體、股份制外,還有外資和合資企業(yè),特別是股份制、民營(yíng)企業(yè)發(fā)展很快。全國(guó)篩分機(jī)械市場(chǎng)年產(chǎn)值約為5億元左右,今年又有大的增長(zhǎng),年產(chǎn)值超過1500萬(wàn)元以上的企業(yè)有10余家[6] 。由于我國(guó)東部經(jīng)濟(jì)發(fā)展較快,篩分機(jī)械制造企業(yè)也主要分布在東北、華北、華東和中南地區(qū),尤其是鞍山新鄉(xiāng)地區(qū),這兩個(gè)地區(qū)的篩分機(jī)械產(chǎn)值約占全國(guó)總產(chǎn)值的50%左右,可是在西部地區(qū),還沒有一家像樣的篩分設(shè)備制造企業(yè)。我國(guó)篩分設(shè)備制造企業(yè)雖然很多,但是真正具備實(shí)力的很少。目前全國(guó)具有獨(dú)立研究開發(fā)新產(chǎn)品能力的企業(yè)不多,大約有3~4家,每年能創(chuàng)新開發(fā)幾個(gè)新產(chǎn)品,而大多數(shù)企業(yè)仍是生產(chǎn)常規(guī)較為陳舊的產(chǎn)品。在產(chǎn)品設(shè)計(jì)和制造水平上,全國(guó)大約只有4~5家企業(yè)的機(jī)械裝備和工藝水平真正具備制造較大篩分機(jī)械的能力[7]。德國(guó)申克和K H D公司是國(guó)際著名的篩分機(jī)械制造企業(yè),他們的新產(chǎn)品開發(fā)是和工程設(shè)計(jì)同時(shí)進(jìn)行的:首先要對(duì)被篩物料的物理、化學(xué)性質(zhì)以及在工藝流程中所需達(dá)到的要求進(jìn)行分析,選擇合理的技術(shù)參數(shù)、進(jìn)行模擬樣機(jī)試制、進(jìn)行必要的設(shè)計(jì)計(jì)算、工作圖設(shè)計(jì)、產(chǎn)品試制、檢驗(yàn)、服務(wù)、工藝試驗(yàn)、跟蹤服務(wù)、產(chǎn)品改進(jìn)設(shè)計(jì)、定型等一系列程序,最后實(shí)現(xiàn)交鑰匙工程[8]。
4、發(fā)展方向
(1)深入研究新的篩分理論和技術(shù)
2002年,中國(guó)礦大機(jī)械廠為解決大型振動(dòng)篩強(qiáng)度問題,提出了超靜定網(wǎng)梁結(jié)構(gòu)理論并使用成功,獲得國(guó)家專利。最近,新鄉(xiāng)威猛集團(tuán)將12臺(tái)2m×3m的節(jié)肢篩組合在一起,形成了目前國(guó)內(nèi)最大的7.2m振動(dòng)篩,用于選煤系統(tǒng)的分級(jí)和脫水、脫介,效果很好。同樣,中國(guó)科技大學(xué)為鐵法礦務(wù)局曉青礦研制了篩框不動(dòng)、篩網(wǎng)振動(dòng)的大型振動(dòng)篩 [9]。
(2)引入現(xiàn)代化設(shè)計(jì)手段,采用新材料、新技術(shù)、新工藝
對(duì)現(xiàn)有的篩分機(jī)械進(jìn)行運(yùn)動(dòng)分析和結(jié)構(gòu)改進(jìn),引入現(xiàn)代化設(shè)計(jì)手段,采用優(yōu)化設(shè)計(jì),計(jì)算機(jī)輔助設(shè)計(jì),用計(jì)算機(jī)對(duì)篩分結(jié)構(gòu)強(qiáng)度進(jìn)行計(jì)算,提高設(shè)計(jì)的可靠性;建立振動(dòng)篩試驗(yàn)臺(tái),對(duì)篩機(jī)產(chǎn)品進(jìn)行檢測(cè)。全面推廣使用新材料、新技術(shù)新工藝。對(duì)振動(dòng)機(jī)械用的鋼材、軸承、彈簧、篩網(wǎng)進(jìn)行專門研究,篩面應(yīng)從金屬篩網(wǎng)向非金屬篩網(wǎng)發(fā)展,應(yīng)用橡膠篩板、聚氨酯篩網(wǎng)、彈性桿篩面;支承元件應(yīng)采用橡膠彈簧和復(fù)合彈簧;推廣環(huán)槽鉚釘和高強(qiáng)度螺栓聯(lián)接[10]。
(3)向標(biāo)準(zhǔn)化、系列化、通用化發(fā)展
提高三化水平,這是便于設(shè)計(jì)、組織專業(yè)生產(chǎn)和保證質(zhì)量的途徑。有些零部件如標(biāo)準(zhǔn)化、通用化了,組織專業(yè)化生產(chǎn),可大大降低成本,提高企業(yè)效益。4.5強(qiáng)化篩機(jī)技術(shù)參數(shù)根據(jù)不同用途研制新篩機(jī)。發(fā)展大型、重型、超重型篩分設(shè)備,篩機(jī)振動(dòng)篩強(qiáng)度可達(dá)5.4以上,篩分面積向27m2以上發(fā)展(德國(guó)一家篩子技術(shù)公司曾生產(chǎn)5m×llm、篩分面積達(dá)55m的篩機(jī)),提高篩機(jī)的處理能力和承載能力[11]。
(4)不斷擴(kuò)大篩機(jī)應(yīng)用領(lǐng)域
根據(jù)不同用途,研制出各種不同型式的篩機(jī),目前,國(guó)內(nèi)對(duì)于細(xì)和超細(xì)物料的分級(jí),含水分7%-13%粘性物料的分級(jí)還存在問題。重機(jī)網(wǎng)曾聯(lián)系國(guó)內(nèi)外需要100目以下,生產(chǎn)能力為15t/h的細(xì)篩,國(guó)內(nèi)就沒廠家能接,我們應(yīng)發(fā)展特殊用途篩分設(shè)備,滿足國(guó)民經(jīng)濟(jì)建設(shè)發(fā)展的需要,并擔(dān)當(dāng)對(duì)外出口的任務(wù)[12]。
二、課題主要研究?jī)?nèi)容
1、振動(dòng)篩分的基本原理
直線振動(dòng)篩(直線篩)工作原理:振動(dòng)篩工作時(shí),兩電機(jī)同步反向放置使激振器產(chǎn)生反向激振力,迫使篩體帶動(dòng)篩網(wǎng)做縱向運(yùn)動(dòng),使其上的物料受激振力而周期性向前拋出一個(gè)射程,從而完成物料篩分作業(yè)[13]。
2、振動(dòng)篩總體方案的比較與確定
經(jīng)過仔細(xì)的研究后選擇下列性能參數(shù)的方案:篩面尺寸1000X2000,篩面層數(shù)1,網(wǎng)孔尺寸2-200,產(chǎn)量21t/h,能耗0.74kw,振幅2mm。
3、主要零件選擇方案的比較與確定
主要螺栓、防撞擊墊片等均采用國(guó)家標(biāo)準(zhǔn),以減少制作成本。
三、主要問題及解決方案
1、振動(dòng)篩降噪措施
緊固振動(dòng)篩上的所有部件,特別是需要經(jīng)常更換的篩板,避免由于個(gè)別部件的松動(dòng)而產(chǎn)生的額外振動(dòng);將沖孔鋼篩板更換為彈性模量小、沖擊噪聲低的聚氨酯篩板或者橡膠篩板;在篩箱的側(cè)板、入料給料口、排料口和接料底盤內(nèi)加貼橡膠板,這樣可以有效地抑制側(cè)板的高頻振動(dòng),減少輻射噪聲;采用柔性輻板齒輪來(lái)代替鋼齒輪,即在齒輪的輻板上利用橡膠彈性體傳遞扭矩,吸收齒輪嚙入、嚙出所造成的振動(dòng);用橡膠彈簧替代鋼制彈簧,以減少?zèng)_擊;在激振器的體外加裝軟式隔聲罩;對(duì)軸承的內(nèi)外套之間加以阻尼處理,軸承的滾動(dòng)體可以制作成空心滾動(dòng)體或者在空心滾動(dòng)體的內(nèi)部加入阻尼材料,這樣能夠減小軸承的振動(dòng)和降低軸承的噪聲[14]。
2、常見故障及處理措施
(1)篩分時(shí)篩子不下料或下料不暢
一是給煤溜槽與篩面之間有落差太小,應(yīng)是其落差在400~500mm之間。二是新更換或新安裝的振動(dòng)篩實(shí)際處理量達(dá)不到理論設(shè)計(jì)時(shí)的處理量,即無(wú)法滿足生產(chǎn)要求,這時(shí)應(yīng)提高篩子角度、加大激振力,如果還無(wú)法滿足要求,就需要對(duì)篩面進(jìn)行改造:將入料端的篩孔加大。還要注意的一點(diǎn)是給料槽寬度要適中,如果過窄,物料則不能均勻地分布于篩面的寬度方向上,篩子的篩分面積也不能合理有效利用,篩分效果將會(huì)受到影響[15]。
(2)篩框斷裂根
據(jù)斷裂力學(xué)的原理,篩框顫抖容易發(fā)生斷裂,所以解決該問題的最佳辦法就是加厚側(cè)板,或者對(duì)激振器附近的側(cè)板局部增加附板以增強(qiáng)整個(gè)篩體的剛性,這樣篩框就不容易發(fā)顫和斷裂了[16]。
(3)軸承過熱
第一種最常見的原因是由于軸承徑向游隙太小。由于振動(dòng)篩上的軸承承載的負(fù)荷較大,頻率較高,且載荷一直是變動(dòng)的,所以軸承必須采用大游隙。如果使用的是普通游隙的軸承,就必須將軸承外圈再次磨削,使之成為大游隙。再者就是軸承壓蓋頂?shù)锰o,也會(huì)造成這種現(xiàn)象。壓蓋與軸承外圍之間必須有一定間隙,以保證軸承正常的散熱和一定的軸向串動(dòng)。該間隙可以通過端蓋和軸承座之間的密封墊來(lái)進(jìn)行調(diào)整[17]。
3、篩分的分級(jí)(根據(jù)篩分的目的)
(1)獨(dú)立篩分
其目的是得到適合于用戶要求的最終產(chǎn)品。例如,在黑色冶金工業(yè)中,常把含鐵較高的富鐵礦篩分成不同的粒級(jí),合格的大塊鐵礦石進(jìn)入高爐冶煉,粉礦則經(jīng)團(tuán)礦或燒結(jié)制塊入爐[18]。
(2)輔助篩分
這種篩分主要用在選礦廠的破碎作業(yè)中,對(duì)破碎作業(yè)起輔助作用。一般又有預(yù)先篩分和檢查篩分之別。預(yù)先篩分是指礦石進(jìn)入破碎機(jī)前進(jìn)行的篩分,用篩子從礦石中分出對(duì)于該破碎機(jī)而言已經(jīng)是合格的部分,如粗碎機(jī)前安裝的格條篩,篩分其篩下產(chǎn)品。這樣就可以減少進(jìn)入破碎機(jī)的礦石量,可提高破碎機(jī)的產(chǎn)量。
(3)準(zhǔn)備篩分
其目的是為下一作業(yè)做準(zhǔn)備。如重選廠在跳汰前要把物料進(jìn)行篩分分級(jí),把粗、中、細(xì)不同的產(chǎn)物進(jìn)行分級(jí)淘汰[19]。
(4)選擇篩分
如果物料中有用成分在各個(gè)粒級(jí)的分布差別很大,則可以經(jīng)篩分分級(jí)得到質(zhì)量不同的粒級(jí),把低質(zhì)量的粒級(jí)篩除,從而相應(yīng)提高了物料的品位,有時(shí)又把這種篩分叫篩選。
(5)脫水篩分
篩分的目的是脫除物料的水分,一般在洗煤廠比較常見。此外,物料含水含泥較高時(shí),也用篩分進(jìn)行脫泥[20]。
四、日程安排
第4周:查找畢業(yè)設(shè)計(jì)資料及外文翻譯資料并綜述
第5周:外文翻譯
第6周:完成開題報(bào)告
第7周:總體方案設(shè)計(jì)
第8周:運(yùn)動(dòng)學(xué)與動(dòng)力學(xué)參數(shù)的選擇與計(jì)算
第9~10周:裝配圖設(shè)計(jì)
第11周:完成裝配圖
第12~13周:零部件設(shè)計(jì)與修改
第14~15周:撰寫并完善畢業(yè)設(shè)計(jì)說(shuō)明書
第16周:準(zhǔn)備答辯
第17周:答辯
五、參考文獻(xiàn):
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[9]聞邦椿.振動(dòng)給料機(jī),振動(dòng)輸送機(jī)與振動(dòng)篩的設(shè)計(jì)[M].北京:化學(xué)工業(yè)出版社,1989
[10]聞邦椿、劉樹英.振動(dòng)機(jī)械的理論與動(dòng)態(tài)設(shè)計(jì)方法[M].北京:機(jī)械工業(yè)出版社,2001
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[12]趙國(guó)珍等.鉆井振動(dòng)篩的工作原理與測(cè)試技術(shù)[D].北京:石油工業(yè)出版社,1984
[13]吳佳常.機(jī)械制造工藝學(xué)[M].北京:中國(guó)標(biāo)準(zhǔn)出版社,1992
[14]Li Meng. Journal of Coal Science and Engineering[M].et,1998
[15]柳連舜、霍光庶.譯鋁生產(chǎn)機(jī)械化[D].中國(guó)有色金屬工業(yè)總公司輕金屬編輯部.1991.
[16] 張國(guó)柱編譯.慣性圓錐破碎機(jī)結(jié)構(gòu)探討[J].礦山機(jī)械,1992(6)
[17] 任德樹.粉碎篩分原理與設(shè)備[M].北京;冶金工業(yè)出版社,1984
[18] 陳懋圻.機(jī)械制造工藝學(xué)[M].沈陽(yáng):遼寧科學(xué)技術(shù)出版社,1986
[19] 李留全.KID型慣性圓錐破碎機(jī)用于金剛石礦物處理[J].礦山機(jī)械,1995
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Proceedings of the Thied symposium on Steai Crossing,Edited by Jon Krokedorg
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