大傾角帶式輸送機設(shè)計【優(yōu)秀通過答辯】
大傾角帶式輸送機設(shè)計【優(yōu)秀通過答辯】,優(yōu)秀通過答辯,傾角,輸送,設(shè)計,優(yōu)秀,通過,答辯
大傾角帶式輸送機設(shè)計
摘要：本設(shè)計是關(guān)于大傾角帶式輸送機的設(shè)計，著重參考了多種機械手冊。針對上運、雙滾筒驅(qū)動，以掌握帶式輸送機的設(shè)計，提高我的機械設(shè)計的能力。 首先對帶式輸送機的主要部件、工作原理、布置方式和主要特點等作了簡單的概述；其次分析了帶式輸送機的選型原則及計算方法；之后根據(jù)這些設(shè)計準則與計算選型方法按照給定參數(shù)要求進行選型設(shè)計；最后對所選擇的輸送機各主要零部件進行了校核。
帶式輸送機，結(jié)構(gòu)簡單，運行平穩(wěn)，生產(chǎn)率高，易于控制，性能優(yōu)良，在使用中要趨利避害，重視維護。國內(nèi)帶式輸送機的品種較多，技術(shù)水平有了很大提高，關(guān)鍵技術(shù)研究和新產(chǎn)品開發(fā)都取得了很大的進步。本次帶式輸送機設(shè)計代表了設(shè)計的一般過程, 對今后的選型設(shè)計工作也有參考價值。
關(guān)鍵詞：帶式輸送機；選型；校核
Design of Steeply Inclined Belt Conveyor
Abstract:The design is a graduation project about the belt conveyor with large inclination, especially with reference to a variety of mechanical manuals.It focuses on upward transport of double drive belt conveyor, to master the design of the belt conveyor,and to improve my ability of mechanical design.At first, it is introduction about the belt conveyor. Next, it is the principles about choosing component parts of belt conveyor. After that the belt conveyor based on the principle is designed. Then, it is checking computations about main component parts.
Belt conveyor has the advantages of simple structure, stable operation, high productivity, easy controlling and good performance.In use, we should hasten benefit , avoid harm, and pay attention to maintenance.More varieties of domestic conveyor technology has been greatly improved, and research on key technology and new product development have made great progress.This belt conveyor design represents the general process of design.And it also has a certain reference value to the design in the future.
Key words:belt conveyor；lectotype；checking
目 錄
1 概述 1
1.1 主要部件 1
1.2 工作原理 2
1.3 布置方式 3
1.4 主要特點 4
2 DT II（A）型帶式輸送機的設(shè)計計算 5
2.1 原始數(shù)據(jù)及工作條件 5
2.2 輸送能力、輸送帶寬度 7
2.2.1 帶寬的選擇 7
2.2.2 帶寬的核算 8
2.3 圓周驅(qū)動力 8
2.3.1 計算公式 8
2.3.2 主要阻力 9
2.3.3 主要特種阻力 10
2.3.4 附加特種阻力 11
2.3.5 傾斜阻力 12
2.4 傳動功率 13
2.4.1 傳動軸功率 13
2.4.2 電動機功率 13
2.5 輸送帶張力 14
2.5.1 輸送帶不打滑條件校核 14
2.5.2 輸送帶下垂度校核 15
2.5.3 各特性點張力計算 16
2.6 傳動滾筒、改向滾筒 17
2.6.1 傳動滾筒合張力 17
2.6.2 改向滾筒合張力 18
2.6.3 確定傳動滾筒 19
2.6.4 確定驅(qū)動裝置 19
2.7 拉緊裝置 19
2.8 輸送帶的選擇 20
3 主要部件的選用 21
3.1 輸送帶 21
3.1.1 分類 21
3.1.2 連接 22
3.1.3 選型 22
3.2 托輥 23
3.2.1 作用 23
3.2.2 類型 23
3.2.3 選型 25
3.2.4 校核 29
3.3 滾筒 30
3.3.1 作用及類型 30
3.3.2 選型及設(shè)計 31
3.3.3 轉(zhuǎn)向滾筒 32
3.4 驅(qū)動裝置 32
3.4.1 傳動滾筒 33
3.4.2 電動機 33
3.4.3 減速器 33
3.5 制動裝置 34
3.5.1 作用 34
3.5.2 種類 34
3.5.3 選型 36
3.6 拉緊裝置 36
3.6.1 作用 36
3.6.2 在使用中應(yīng)滿足的要求 36
3.6.3 在過渡工況下的工作特點 37
3.6.4 布置時應(yīng)遵循的原則 37
3.6.5 種類及特點 38
3.7 機架 40
3.7.1 頭架 41
3.7.2 尾架 41
3.7.3 中間架 41
4 其他部件的選用 42
4.1 給料裝置 42
4.1.1 對給料裝置的基本要求 42
4.1.2 裝料段攔板的布置及尺寸 42
4.1.3 裝料點的緩沖 43
4.2 卸料裝置 44
4.3 清掃裝置 45
4.3.1 篦子式刮板清掃裝置 45
4.3.2 輸送機式刮板清掃裝置 46
4.3.3 刷式清掃裝置 46
4.3.4 振動式清掃裝置 47
4.3.5 水力和風力清掃裝置 48
4.3.6 聯(lián)合清掃裝置 48
4.3.7 輸送帶翻轉(zhuǎn)裝置 49
4.3.8 清掃裝置的種類及應(yīng)用情況分析 51
4.4 頭部漏斗 54
4.5 安保裝置 55
4.6 改向裝置 55
結(jié)論 57
參考文獻 58
附錄 59
致謝 71
1 概述
帶式輸送機，又稱膠帶輸送機，是一種摩擦驅(qū)動以連續(xù)方式運輸物料的機械。帶式輸送機將物料在一定的輸送線上，從最初的供料點到最終的卸料點間形成一種物料的輸送流程。它既可以進行碎散物料的輸送，也可以進行成件物品的輸送。除進行純粹的物料輸送外，還可以與各工業(yè)企業(yè)生產(chǎn)流程中的工藝過程的要求相配合，形成有節(jié)奏的流水作業(yè)運輸線。
DTⅡ（A）型固定式帶式輸送機是通用型系列產(chǎn)品，可廣泛用于冶金、煤炭、交通、電力、建材、化工、輕工、糧食和機械行業(yè)。輸送松散密度為500~2500kg/m3的各種散裝物料及成件物品，適用環(huán)境溫度為-20℃~40℃，被送物料溫度小于60℃。對于有耐熱、耐寒、防腐、防爆、阻燃等條件，應(yīng)選用特種橡膠輸送帶并采用相應(yīng)防護措施。［1］北京起重運輸機械研究所，武漢豐凡科技開發(fā)有限責任公司.DTⅡ（A）型帶式輸送機
設(shè)計手冊[M].第1版.北京:冶金工業(yè)出版社，2003
在輸送原煤時，設(shè)計向上最大輸送傾角一般為17°~18°。本次設(shè)計傾角為16°，相對于12°、14°，傾角較大，故定名為大傾角帶式輸送機設(shè)計。
1.1 主要部件
帶式輸送機的主要部件有輸送帶、托輥、滾筒、驅(qū)動裝置、制動裝置、拉緊裝置和清掃裝置等［2］程居山，王昌田，李新平等.礦山機械[M].第1版.徐州:中國礦業(yè)大學(xué)出版社，2005
［3］劉鴻文.材料力學(xué)[M].第4版.北京：高等教育出版社，2004
［4］《運輸機械設(shè)計選用手冊》編組委.運輸機械設(shè)計選用手冊（上、下）[M].北京:化學(xué)工業(yè)
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［5］王蘭美，殷昌貴.畫法幾何及工程制圖[M].第2版.北京:機械工業(yè)出版社，2007
［6］鄭笑紅.AutoCAD應(yīng)用基礎(chǔ)[M].第1版.徐州:中國礦業(yè)大學(xué)出版社，2007
［7］唐金松.簡明機械設(shè)計手冊[M].第2版.上海:上?？茖W(xué)技術(shù)出版社.2002
［8］機械化運輸設(shè)計手冊編委會.機械化運輸設(shè)計手冊[M].機械工業(yè)出版社.1997年5月.
［9］張鉞.新型帶式輸送機設(shè)計手冊[M].冶金工業(yè)出版社.2001年2月.
［10］李紅玉.帶式輸送機自動調(diào)偏滾筒.礦業(yè)快報.2004,4(4):36.
［11］張文芳，段志強，邊會杰.帶式輸送機防跑偏輥及清掃器的使用與研究[J].河北煤
炭.2002,5:9-10.
［12］陳炳耀，祁開陽.帶式輸送機輸送帶與滾筒之間的打滑分析[J].煤礦機械,2003(5):49-51.
［13］王傳海，張衛(wèi)國.帶式輸送機斷帶及飛車制動保護裝置[J].礦業(yè)安全與環(huán)保
2003,30(3):40-46.
［14］史志遠，朱真才.帶式輸送機斷帶保護裝置分析[J].煤礦機械,2005(8):83-85.
［15］禹金云.機械安全技術(shù)趨向分析[J].中國安全科學(xué)學(xué)報,2004,14(4):54-56.
附錄
Basic Machining Operations and Cutting Technology
1 Basic Machine Tools
Machine tools are used to produce a part of a specified geometrical shape and precise I size by removing metal from a ductile material in the form of chips. The latter are a waste product and vary from long continuous ribbons of a ductile material such as steel, which are undesirable from a disposal point of view, to easily handled well-broken chips resulting from cast iron. Machine tools perform five basic metal-removal processes: turning, planning, drilling, milling and grinding. All other metal-removal processes are modifications of these five basic processes. For example, boring is internal turning; reaming, tapping, and counter boring modify drilled holes and are related to drilling; bobbing and gear cutting are fundamentally milling operations; hack sawing and broaching are a form of planning and honing; lapping, super finishing. Polishing and buffing are variants of grinding or abrasive removal operations. Therefore, there are only four types of basic machine tools, which use cutting tools of specific controllable geometry: 1. lathes, 2. planers, 3. drilling machines, and 4. milling machines. The grinding process forms chips, but the geometry of the abrasive grain is uncontrollable.
The amount and rate of material removed by the various machining processes may be I large, as in heavy turning operations, or extremely small, as in lapping or super finishing operations where only the high spots of a surface are removed.
A machine tool performs three major functions: 1. it rigidly supports the workpiece or its holder and the cutting tool; 2. it provides relative motion between the workpiece and the cutting tool; 3. it provides a range of feeds and speeds usually ranging from 4 to 32 choices in each case.
2 Speed and Feeds in Machining
Speeds, feeds, and depth of cut are the three major variables for economical machining. Other variables are the work and tool materials, coolant and geometry of the cutting tool. The rate of metal removal and power required for machining depend upon these variables.
The depth of cut, feed, and cutting speed are machine settings that must be established in any metal-cutting operation. They all affect the forces, the power, and the rate of metal removal. They can be defined by comparing them to the needle and record of a phonograph. The cutting speed (V) is represented by the velocity of- the record surface relative to the needle in the tone arm at any instant. Feed is represented by the advance of the needle radially inward per revolution, or is the difference in position between two adjacent grooves. The depth of cut is the penetration of the needle into the record or the depth of the grooves.
3 Turning on Lathe Centers
The basic operations performed on an engine lathe are illustrated. Those operations performed on external surfaces with a single point cutting tool are called turning. Except for drilling, reaming, and lapping, the operations on internal surfaces are also performed by a single point cutting tool.
All machining operations, including turning and boring, can be classified as roughing, finishing, or semi-finishing. The objective of a roughing operation is to remove the bulk of the material as rapidly and as efficiently as possible, while leaving a small amount of material on the work-piece for the finishing operation. Finishing operations are performed to obtain the final size, shape, and surface finish on the workpiece. Sometimes a semi-finishing operation will precede the finishing operation to leave a small predetermined and uniform amount of stock on the work-piece to be removed by the finishing operation.
Generally, longer workpieces are turned while supported on one or two lathe centers. Cone shaped holes, called center holes, which fit the lathe centers are drilled in the ends of the workpiece-usually along the axis of the cylindrical part. The end of the workpiece adjacent to the tailstock is always supported by a tailstock center, while the end near the headstock may be supported by a headstock center or held in a chuck. The headstock end of the workpiece may be held in a four-jaw chuck, or in a type chuck. This method holds the workpiece firmly and transfers the power to the workpiece smoothly; the additional support to the workpiece provided by the chuck lessens the tendency for chatter to occur when cutting. Precise results can be obtained with this method if care is taken to hold the workpiece accurately in the chuck.
Very precise results can be obtained by supporting the workpiece between two centers. A lathe dog is clamped to the workpiece; together they are driven by a driver plate mounted on the spindle nose. One end of the Workpiece is mecained;then the workpiece can be turned around in the lathe to machine the other end. The center holes in the workpiece serve as precise locating surfaces as well as bearing surfaces to carry the weight of the workpiece ?and to resist the cutting forces. After the workpiece has been removed from the lathe for any reason, the center holes will accurately align the workpiece back in the lathe or in another lathe, or in a cylindrical grinding machine. The workpiece must never be held at the headstock end by both a chuck and a lathe center. While at first thought this seems like a quick method of aligning the workpiece in the chuck, this must not be done because it is not possible to press evenly with the jaws against the workpiece while it is also supported by the center. The alignment provided by the center will not be maintained and the pressure of the jaws may damage the center hole, the lathe center, and perhaps even the lathe spindle. Compensating or floating jaw chucks used almost exclusively on high production work provide an exception to the statements made above. These chucks are really work drivers and cannot be used for the same purpose as ordinary three or four-jaw chucks.
While very large diameter workpieces are sometimes mounted on two centers, they are preferably held at the headstock end by faceplate jaws to obtain the smooth power transmission; moreover, large lathe dogs that are adequate to transmit the power not generally available, although they can be made as a special. Faceplate jaws are like chuck jaws except that they are mounted on a faceplate, which has less overhang from the spindle bearings than a large chuck would have.
4 Primary Cutting Parameters
The basic tool-work relationship in cutting is adequately described by means of four factors: tool geometry, cutting speed, feed, and depth of cut.
The cutting tool must be made of an appropriate material; it must be strong, tough, hard, and wear resistant. The tool s geometry characterized by planes and angles, must be correct for each cutting operation. Cutting speed is the rate at which the work surface passes by the cutting edge. It may be expressed in feet per minute.
For efficient machining the cutting speed must be of a magnitude appropriate to the particular work-tool combination. In general, the harder the work material, the slower the speed.
Feed is the rate at which the cutting tool advances into the workpiece. "Where the workpiece or the tool rotates, feed is measured in inches per revolution. When the tool or the work reciprocates, feed is measured in inches per stroke, Generally, feed varies inversely with cutting speed for otherwise similar conditions.
The depth of cut, measured inches is the distance the tool is set into the work. It is the width of the chip in turning or the thickness of the chip in a rectilinear cut. In roughing operations, the depth of cut can be larger than for finishing operations.
5 Wears of Cutting Tool
Discounting brittle fracture and edge chipping, which have already been dealt with, tool wear is basically of three types. Flank wear, crater wear, and notch wear. Flank wear occurs on both the major and the minor cutting edges. On the major cutting edge, which is responsible for bulk metal removal, these results in increased cutting forces and higher temperatures which if left unchecked can lead to vibration of the tool and workpiece and a condition where efficient cutting can no longer take place. On the minor cutting edge, which determines workpiece size and surface finish, flank wear can result in an oversized product which has poor surface finish. Under most practical cutting conditions, the tool will fail due to major flank wear before the minor flank wear is sufficiently large to result in the manufacture of an unacceptable component.
Because of the stress distribution on the tool face, the frictional stress in the region of sliding contact between the chip and the face is at a maximum at the start of the sliding contact region and is zero at the end. Thus abrasive wear takes place in this region with more wear taking place adjacent to the seizure region than adjacent to the point at which the chip loses contact with the face. This result in localized pitting of the tool face some distance up the face which is usually referred to as catering and which normally has a section in the form of a circular arc. In many respects and for practical cutting conditions, crater wear is a less severe form of wear than flank wear and consequently flank wear is a more common tool failure criterion. However, since various authors have shown that the temperature on the face increases more rapidly with increasing cutting speed than the temperature on the flank, and since the rate of wear of any type is significantly affected by changes in temperature, crater wear usually occurs at high cutting speeds.
At the end of the major flank wear land where the tool is in contact with the uncut workpiece surface it is common for the flank wear to be more pronounced than along the rest of the wear land. This is because of localised effects such as a hardened layer on the uncut surface caused by work hardening introduced by a previous cut, an oxide scale, and localised high temperatures resulting from the edge effect. This localised wear is usually referred to as notch wear and occasionally is very severe. Although the presence of the notch will not significantly affect the cutting properties of the tool, the notch is often relatively deep and if cutting were to continue there would be a good chance that the tool would fracture.
If any form of progressive wear allowed to continue, dramatically and the tool would fail catastrophically, i. e. the tool would be no longer capable of cutting and, at best, the workpiece would be scrapped whilst, at worst, damage could be caused to the machine tool. For carbide cutting tools and for all types of wear, the tool is said to have reached the end of its useful life long before the onset of catastrophic failure. For high-speed-steel cutting tools, however, where the wear tends to be non-uniform it has been found that the most meaningful and reproducible results can be obtained when the wear is allowed to continue to the onset of catastrophic failure even though, of course, in practice a cutting time far less than that to failure would be used. The onset of catastrophic failure is characterized by one of several phenomena, the most common being a sudden increase in cutting force, the presence of burnished rings on the workpiece, and a significant increase in the noise level.
6 Mechanism of Surface Finish Production
There are basically five mechanisms which contribute to the production of a surface which have been machined. These are
(l) The basic geometry of the cutting process. In, for example, single point turning the tool will advance a constant distance axially per revolution of the workpiece and the resultant surface will have on it, when viewed perpendicularly to the direction of tool feed motion, a series of cusps which will have a basic form which replicates the shape of the tool in cut.
(2) The efficiency of the cutting operation. It has already been mentioned that cutting with unstable built-up-edges will produce a surface which contains hard built-up-edge fragments which will result in a degradation of the surface finish. It can also be demonstrated that cutting under adverse conditions such as apply when using large feeds small rake angles and low cutting speeds, besides producing conditions which lead to unstable built-up-edge production, the cutting process itself can become unstable and instead of continuous shear occurring in the shear zone, tearing takes place, discontinuous chips of uneven thickness are produced, and the resultant surface is poor. This situation is particularly noticeable when machining very ductile materials such as copper and aluminum.
(3) The stability of the machine tool. Under some combinations of cutting conditions; workpiece size, method of clamping ,and cutting tool rigidity relative to the machine tool structure, instability can be set up in the tool which causes it to vibrate. Under some conditions this vibration will reach and maintain steady amplitude whilst under other conditions the vibration will built up and unless cutting is stopped considerable damage to both the cutting tool and workpiece may occur. This phenomenon is known as chatter and in axial turning is characterized by long pitch helical bands on the workpiece surface and short pitch undulations on the transient machined surface.
(4)The effectiveness of removing swarf. In discontinuous chip production machining, such as milling or turning of brittle materials, it is expected that the chip (swarf) will leave the cutting zone either under gravity or with the assistance of a jet of cutting fluid and that they will not influence the cut surface in any way. However, when continuous chip production is evident, unless steps are taken to control the swarf it is likely that it will impinge on the cut surface and mark it. Inevitably, this marking besides looking.
(5)The effective clearance angle on the cutting tool. For certain geometries of minor cutting edge relief and clearance angles it is possible to cut on the major cutting edge and burnish on the minor cutting edge. This can produce a good surface finish but, of course, it is strictly a combination of metal cutting and metal forming and is not to be recommended as a practical cutting method. However, due to cutting tool wear, these conditions occasionally arise and lead to a marked change in the surface characteristics.
7 Limits and Tolerances
Machine parts are manufactured so they are interchangeable. In other words, each part of a machine or mechanism is made to a certain size and shape so will fit into any other machine or mechanism of the same type. To make the part interchangeable, each individual part must be made to a size that will fit the mating part in the correct way. It is not only impossible, but also impractical to make many parts to an exact size. This is because machines are not perfect, and the tools become worn. A slight variation from the exact size is always allowed. The amount of this variation depends on the kind of part being manufactured. For examples part might be made 6 in. long with a variation allowed of 0.003 (three-thousandths) in. above and below this size. Therefore, the part could be 5.997 to 6.003 in. and still be the correct size. These are known as the limits. The difference between upper and lower limits is called the tolerance.
A tolerance is the total permissible variation in the size of a part.
The basic size is that size from which limits of size arc derived by the application of allowances and tolerances.
Sometimes the limit is allowed in only one direction. This is known as unilateral tolerance.
Unilateral tolerancing is a system of dimensioning where the tolerance (that is variation) is shown in only one direction from the nominal size. Unilateral tolerancing allow the changi
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