50 10t桥式起重机大车运行机构及整体结构的设计
最新十吨位桥式起重机大车运行机构设计
十吨位桥式起重机大车运行机构设计毕业设计（论文）相关资料题目：十吨位桥式起重机大车运行机构设计目录一、毕业设计（论文）开题报告二、毕业设计（论文）外文资料翻译及原文三、学生“毕业论文（论文）计划、进度、检查及落实表”四、实习鉴定表无锡太湖学院毕业设计（论文）开题报告题目：十吨位桥式起重机大车运行机构设计信机系机械工程及自动专业学号： 0923087学生姓名：叶宏城指导教师：陈炎冬（职称：讲师）（职称：）2012年11月25日外文资料翻译及原文英文原文：Fatigue life prediction of the metalwork of a travelling gantrycraneAbstractIntrinsic fatigue curves are applied to a fatigue life prediction problem of the metalwork of a traveling gantry crane. A crane, used in the forest industry, was studied in working conditions at a log yard, an strain measurements were made. For the calculations of the number of loading cycles, the rain flow cycle counting technique is used. The operations of a sample of such cranes were observed for a year for the average number of operation cycles to be obtained. The fatigue failure analysis has shown that failures some elements are systematic in nature and cannot be explained by random causes.卯1999 Elsevier Science Ltd. All rights reserved.Key words: Cranes; Fatigue assessment; Strain gauging1. IntroductionFatigue failures of elements of the metalwork of traveling gantry cranes LT62B are observed frequently in operation. Failures as fatigue cracks initiate and propagate in welded joints of the crane bridge and supports in three-four years. Such cranes are used in the forest industry at log yards for transferring full-length and sawn logs to road trains, having a load-fitting capacity of 32 tons. More than 1000 cranes of this type work at the enterprises of the Russian forest industry. The problem was stated to find the weakest elements limiting the cranes' fives, predict their fatigue behavior, and give recommendations to the manufacturers for enhancing the fives of the cranes.2. Analysis of the crane operationFor the analysis, a traveling gantry crane LT62B installed at log yard in the Yekaterinburg region was chosen. The crane serves two saw mills, creates a log store, and transfers logs to or out of road trains. A road passes along the log store. The saw mills are installed so that the reception sites are under the crane span. A schematic view of the crane is shown in Fig. 1.1350-6307/99/$一see front matter 1999 Elsevier Science Ltd. All rights reserved. PII: S 1 3 5 0一6307(98) 00041一7A series of assumptions may be made after examining the work of cranes:·if the monthly removal of logs from the forest exceeds the processing rate, i.e. there is a creation of a log store, the crane expects work, being above the centre of a formed pile with the grab lowered on the pile stack;·when processing exceeds the log removal from the forest, the crane expects work above an operational pile close to the saw mill with the grab lowered on the pile; ·the store of logs varies; the height of the piles is considered to be a maximum;·the store variation takes place from the side opposite to the saw mill;·the total volume of a processed load is on the average k=1.4 times more than the total volume of removal because of additional transfers.2.1. Removal intensityIt is known that the removal intensity for one year is irregular and cannot be considered as a stationary process. The study of the character of non-stationary flow of road trains at 23 enterprises Sverdlesprom for five years has shown that the monthly removal intensity even for one enterprise essentially varies from year to year. This is explained by the complex of various systematic and random effects which exert an influence on removal: weather conditions, conditions of roads and lorry fleet, etc. All wood brought to the log store should, however, be processed within one year. Therefore, the less possibility of removing wood in the season between spring and autumn, the more intensively the wood removal should be performed in winter. While in winter the removal intensity exceeds the processing considerably, in summer, in most cases, the more full-length logs are processed than are taken out.From the analysis of 118 realizations of removal values observed for one year, it is possible to evaluate the relative removal intensity g(t) as percentages of the annualload turnover. The removal data fisted in Table 1 is considered as expected values for any crane, which can be applied to the estimation of fatigue life, and, particularly, for an inspected crane with which strain measurement was carried out (see later). It would be possible for each crane to take advantage of its load turnover per one month, but to establish these data without special statistical investigation is difficult. Besides, to solve the problem of life prediction a knowledge of future loads is required, which we take as expected values on cranes with similar operation conditions.The distribution of removal value Q(t) per month performed by the relative intensityq(t) is written aswhere Q is the annual load turnover of a log store, A is the maximal designed store of logs in percent of Q. Substituting the value Q, which for the inspected crane equals 400,000 m3 per year, and A=10%, the volumes of loads transferred by the crane are obtained, which are listed in Table 2, with the total volume being 560,000 m3 for one year using K,.2.2. Number of loading blocksThe set of operations such as clamping, hoisting, transferring, lowering, and getting rid of a load can be considered as one operation cycle (loading block) of the crane. As a result to investigations, the operation time of a cycle can be modeled by the normal variable with mean equal to 11.5 min and standard deviation to 1.5 min. unfortunately, this characteristic cannot be simply used for the definition of the number of operation cycles for any work period as the local processing is extremely irregular. Using a total operation time of the crane and evaluations of cycle durations, it is easy to make large errors and increase the number of cycles compared with the real one. Therefore, it is preferred to act as follows.The volume of a unit load can be modeled by a random variable with a distribution function(t) having mean22 m3 and standard deviation 6;一3 m3, with the nominalvolume of one pack being 25 m3. Then, knowing the total volume of a processed load for a month or year, it is possible to determine distribution parameters of the number of operation cycles for these periods to take advantage of the methods of renewal theory [1].According to these methods, a random renewal process as shown in Fig. 2 is considered, where the random volume of loads forms a flow of renewals:In renewal theory, realizations of random:，，，having a distribution function F-(t),are understoodas moments of recovery of failed units or request receipts. The value of a processedload:，，after}th operation is adopted here as the renewal moment.＜t﹜. The function F-(t) is defined recurrently,Let F(t)=P﹛nLet v(t) be the number of operation cycles for a transferred volume t. In practice, the total volume of a transferred load t is essentially greater than a unit load, and it is useful therefore totake advantage of asymptotic properties of the renewal process. As follows from an appropriatelimit renewal theorem, the random number of cycles v required to transfer the large volume t hasthe normal distribution asymptotically with mean and variance.without dependence on the form of the distribution function月t) of a unit load (the restriction isimposed only on nonlattice of the distribution).Equation (4) using Table 2 for each averaged operation month,function of number of load cycles with parameters m,. and 6,., which normal distribution in Table 3. Figure 3 shows the average numbers of cycles with 95 % confidence intervals. The values of these parametersfor a year are accordingly 12,719 and 420 cycles.3. Strain measurementsIn order to reveal the most loaded elements of the metalwork and to determine a range of stresses, static strain measurements were carried out beforehand. Vertical loading was applied by hoisting measured loads, and skew loading was formed with a tractor winch equipped with a dynamometer. The allocation schemes of the bonded strain gauges are shown in Figs 4 and 5. As was expected, the largest tension stresses in the bridge take place in the bottom chord of the truss (gauge 11-45 MPa). The top chord of the truss is subjected to the largest compression stresses.The local bending stresses caused by the pressure of wheels of the crane trolleys are added to the stresses of the bridge and the load weights. These stresses result in the bottom chord of the I一beam being less compressed than the top one (gauge 17-75 and 10-20 MPa). The other elements of the bridge are less loaded with stresses not exceeding the absolute value 45 MPa. The elements connecting the support with the bridge of the crane are loaded also irregularly. The largest compression stresses take place in the carrying angles of the interior panel; the maximum stresses reach h0 MPa (gauges 8 and 9). The largest tension stresses in the diaphragms and angles of the exterior panel reach 45 MPa (causes 1 and hl.The elements of the crane bridge are subjected, in genera maximum stresses and respond weakly to skew loads. The suhand, are subjected mainly to skew loads.1, to vertical loads pports of the crane gmmg rise to on the otherThe loading of the metalwork of such a crane, transferring full-length logs, differs from that ofa crane used for general purposes. At first, it involves the load compliance of log packs because ofprogressive detachment from the base. Therefore, the loading increases rather slowly and smoothly.The second characteristic property is the low probability of hoisting with picking up. This is conditioned by the presence of the grab, which means that the fall of the rope from the spreader block is not permitted; the load should always be balanced. The possibility of slack being sufficient to accelerate an electric drive to nominal revolutions is therefore minimal. Thus, the forest traveling gantry cranes are subjected to smaller dynamic stresses than in analogous cranes for general purposes with the same hoisting speed. Usually, when acceleration is smooth, the detachment of a load from the base occurs in 3.5-4.5 s after switching on an electric drive. Significant oscillations of the metalwork are not observed in this case, and stresses smoothly reach maximum values.When a high acceleration with the greatest possible clearance in the joint between spreader andgrab takes place, the tension of the ropes happens 1 s after switching the electric drive on, theclearance in the joint taking up. The revolutions of the electric motors reach the nominal value inO.}r0.7 s. The detachment of a load from the base, from the moment of switching electric motorson to the moment of full pull in the ropes takes 3-3.5 s, the tensions in ropes increasing smoothlyto maximum. The stresses in the metalwork of the bridge and supports grow up to maximumvalues in 1-2 s and oscillate about an average within 3.5%.When a rigid load is lifted, the accelerated velocity of loading in the rope hanger and metalworkis practically the same as in case of fast hoisting of a log pack. The metalwork oscillations are characterized by two harmonic processes with periods 0.6 and 2 s, which have been obtained from spectral analysis. The worst case of loading ensues from summation of loading amplitudes so that the maximum excess of dynamic loading above static can be 13-14%.Braking a load, when it is lowered, induces significant oscillation of stress in the metalwork, which can be }r7% of static loading. Moving over rail joints of 3} mm height misalignment induces only insignificant stresses. In operation, there are possible cases when loads originating from various types of loading combine. The greatest load is the case when the maximum loads from braking of a load when lowering coincide with braking of the trolley with poorly adjusted brakes.4. Fatigue loading analysisStrain measurement at test points, disposed as shown in Figs 4 and 5, was carried out during the work of the crane and a representative number of stress oscillograms was obtained. Since a common operation cycle duration of the crane has a sufficient scatter with average value } 11.5min, to reduce these oscillograms uniformly a filtration was implemented to these signals, and all repeated values, i.e. while theconstruction was not subjected to dynamic loading and only static loading occurred, were rejected. Three characteristic stress oscillograms (gauge 11) are shown inFig. 6 where the interior sequence of loading for an operation cycle is visible. At first, stressesincrease to maximum values when a load is hoisted. After that a load is transferred to the necessary location and stresses oscillate due to the irregular crane movement on rails and over rail joints resulting mostly in skew loads. The lowering of the load causes the decrease of loading and forms half of a basic loading cycle.4.1. Analysis of loading process amplitudesTwo terms now should be separated: loading cycle and loading block. The first denotes one distinct oscillation of stresses (closed loop), and the second is for the set of loading cycles during an operation cycle. The rain flow cycle counting method given in Ref. [2] was taken advantage of to carry out the fatigue hysteretic loop analysis for the three weakest elements: (1) angle of the bottom chord(gauge 11), (2) I-beam of the top chord (gauge 17), (3) angle of the support (gauge 8). Statistical evaluation of sample cycle amplitudes by means of the Waybill distribution for these elements has given estimated parameters fisted in Table 4. It should be noted that the histograms of cycle amplitude with nonzero averages were reduced afterwards to equivalent histograms with zero averages.4.2. Numbers of loading cyclesDuring the rain flow cycle counting procedure, the calculation of number of loading cycles for the loading block was also carried out. While processing the oscillograms of one type, a sample number of loading cycles for one block is obtained consisting ofintegers with minimum and maximum observed values: 24 and 46. The random number of loading cycles vibe can be describedby the Poisson distribution with parameter =34.Average numbers of loading blocks via months were obtained earlier, so it is possible to find the appropriate characteristics not only for loading blocks per month, but also for the total number of loading cycles per month or year if the central limit theorem is taken advantage of. Firstly, it is known from probability theory that the addition of k independent Poisson variables gives also a random variable with the Poisson distribution with parameter k},. On the other hand, the Poisson distribution can be well approximated by the normal distribution with average}, and variation },. Secondly, the central limit theorem, roughly speaking, states that the distribution of a large number of terms, independent of the initial distribution asymptotically tends to normal. If the initial distribution of each independent term has a normal distribution, then the average and standard deviation of the total number of loading cycles for one year are equal to 423,096 and 650 accordingly. The values of k are taken as constant averages from Table 3.5. Stress concentration factors and element enduranceThe elements of the crane are jointed by semi-automatic gas welding without preliminary edge preparation and consequent machining. For the inspected elements 1 and 3 having circumferential and edge welds of angles with gusset plates, the effective stress concentration factor for fatigue is given by calculation methods [3],kf=2.}r2.9, coinciding with estimates given in the current Russian norm for fatigue of welded elements [4], kf=2.9.The elements of the crane metalwork are made of alloyed steel 09G2S having an endurance limit of 120 MPa and a yield strength of 350 MPa. Then the average values of the endurance limits of the inspected elements 1 and 3 are ES一l=41 MPa. Thevariation coefficient is taken as 0.1, and the corresponding standard deviation is 6S-、一4.1 MPa.The inspected element 2 is an I-beam pierced by holes for attaching rails to the top flange. The rather large local stresses caused by local bending also promote fatigue damage accumulation. According to tables from [4], the effective stress concentration factor is accepted as kf=1.8, which gives an average value of the endurance limit as ES 一l=h7 Map. Using the same variation coiffing dent th e stand arid d emit ion is 1s σ-=6.7 MPa.An average S-N curve, recommended in [4], has the form:with the inflexion point No=5·106 and the slope m=4.5 for elements 1 and 3 and m=5.5 for element 2.The possible values of the element endurance limits presented above overlap the ranges of load amplitude with nonzero probability, which means that these elements are subjected to fatigue damage accumulation. Then it is possible to conclude that fatigue calculations for the elements are necessary as well as fatigue fife prediction.6. Life predictionThe study has that some elements of the metalwork are subject to fatigue damage accumulation.To predict fives we shall take advantage of intrinsic fatigue curves, which are detailed in [5]and [6].Following the theory of intrinsic fatigue curves, we get lognormal life distribution densities for the inspected elements. The fife averages and standard deviations are fisted in Table 5. The lognormal fife distribution densities are shown in Fig. 7. It is seen from this table that the least fife is for element 3. Recollecting that an average number of load blocks for a year is equal to 12,719, it is clear that the average service fife of the crane before fatigue cracks appear in the welded elements is sufficient: the fife is 8.5 years for element 1, 11.5 years for element 2, and h years for element 3. However, the probability of failure of these elements within three-four years is notsmall and is in the range 0.09-0.22. These probabilities cannot be neglected, and services of design and maintenance should make efforts to extend the fife of the metalwork without permitting crack initiation and propagation.7. ConclusionsThe analysis of the crane loading has shown that some elements of the metalwork are subjectedto large dynamic loads, which causes fatigue damage accumulation followed by fatigue failures.The procedure of fatigue hfe prediction proposed in this paper involves tour parts:(1) Analysis of the operation in practice and determination of the loading blocks for some period.(2) Rainflow cycle counting techniques for the calculation of loading cycles for a period of standard operation.(3) Selection of appropriate fatigue data for material.(4) Fatigue fife calculations using the intrinsic fatigue curves approach.The results of this investigation have been confirmed by the cases observed in practice, and the manufacturers have taken a decision about strengthening the fixed elements to extend their fatigue lives.References[1] Feller W. An introduction to probabilistic theory and its applications, vol. 2. 3rd ed. Wiley, 1970.[2] Rychlik I. International Journal of Fatigue 1987;9:119.[3] Piskunov V(i. Finite elements analysis of cranes metalwork. Moscow: Mashinostroyenie, 1991 (in Russian).[4] MU RD 50-694-90. Reliability engineering. Probabilistic methods of calculations for fatigue of welded metalworks.Moscow: (iosstandard, 1990 (in Russian).[5] Kopnov VA. Fatigue and Fracture of Engineering Materials and Structures 1993;16:1041.[6] Kopnov VA. Theoretical and Applied Fracture Mechanics 1997;26:169.中文翻译龙门式起重机金属材料的疲劳强度预测摘要内在的疲劳曲线应用到龙门式起重机金属材料的疲劳寿命预测问题。
10t双梁桥式起重机
50/10t双梁桥式起重机大车运行机构及主梁设计学生姓名：学生学号：院（系）：年级专业：指导教师：助理指导教师：二〇〇七年六月摘要桥式起重机是起重运输行业中必不可少的重要设备，它的稳定性和可靠性一直受到人们的高度重视。
随着社会生产力的不断进步和生产规模的不断扩大，以及技术创新的不断深入，在大量国外先进技术引入的同时，桥式起重机的生产设计水平也在不断革新，不断提高。
结合生产实际提出了起重机大车运行机构以及主梁的几种方案，通过分析选定方案并对大车运行机构及主梁进行了设计说明，同时，也对起重机的安全检查提出了要求。
为了最大限度的利用资源，达到最大的经济效益，在此也对主梁进行了优化设计，并提出了大量安全措施，从而保证了起重机械稳定可靠的工作。
关键词：桥式起重机；大车运行机构；主梁；优化ABSTRACTThe bridge type hoist crane is the heavy objects for lifting in the transportation profession the essential important equipment, its stability and the reliability receive the people to take highly continuously. Along with social productive forces unceasing progress and scale of production unceasing expansion, as well as technological innovation unceasingly thorough, while massive overseas vanguard technology introduction, the bridge type hoist crane production design level unceasingly is also innovating, enhances unceasingly.The in coor with progress of production proposed actually the hoist crane large cart movement organization as well as king post several kind of plans, have carried on design showing through the analysis designation plan and to the large cart movement organization and the king post, simultaneously, also set the request to the hoist crane security check.For the maximum limit use resources, achieved the maximum economic efficiency, has also carried on the optimized design in this to the king post, and proposed the massive security measure, thus has guaranteed the hoisting machinery stable reliable work.Key words: Bridge type hoist crane；Large cart movement organization；King post；Optimization目录摘要 (I)ABSTRACT .......................................................... I I1 绪论 (1)2 大车运行机构方案拟订以及选择 (3)2.1大车运行机构的几种常用方案 (3)2.1.1低速集中驱动 (3)2.1.2中速集中驱动 (3)2.1.3高速集中驱动 (4)2.1.4分别驱动 (5)2.2大车运行机构方案分析 (5)2.2.1低速集中驱动 (5)2.2.2中速集中驱动 (5)2.2.3高速集中驱动 (6)2.2.4分别驱动 (6)2.3大车运行机构方案选择 (6)3 主梁方案的拟订及选择 (7)3.1主梁常用的几种方案 (7)3.1.1工字钢主梁 (7)3.1.2桁架主梁 (7)3.1.3箱形主梁 (7)3.2主梁方案分析 (9)3.2.1工字钢主梁 (9)3.2.2桁架主梁 (9)3.2.3箱形主梁 (9)3.3主梁方案选择 (9)4 大车运行机构的设计 (11)4.1运行阻力的计算 (11)4.1.1摩擦阻力 (11)4.1.2坡道阻力 (13)4.1.3风阻力 (14)4.2电动机的选择 (15)4.2.1概述 (15)4.2.2电动机静功率 (15)4.2.3电动机初选 (16)4.2.4电动机过载校验 (16)4.2.5电动机发热校验 (17)4.2.6起动时间与起动平均加速度校验 (18)4.2.7选择合适的电动机型号 (18)4.3减速器的选择 (19)4.3.1减速器概述 (19)4.3.2总体设计 (19)4.3.3确定传动比 (20)4.3.4计算传动装置的传动参数 (21)4.3.5齿轮的设计 (22)4.3.6几何尺寸计算 (25)4.3.7齿轮的结构设计 (26)4.3.8低速轴设计 (26)4.3.9轴的结构设计 (27)4.3.10轴上的载荷 (30)4.3.11校核轴承的受命强验算 (30)4.3.12按弯扭合成应力校核的轴的强度 (30)4.3.13减速器型号的选择 (31)4.4制动器的选择 (31)4.4.1制动器概述 (31)4.4.2制动器相关参数的计算 (32)4.4.3制动器型号的选择 (33)4.5联轴器的选择 (34)4.6运行打滑验算 (34)4.6.1起动时不打滑按下式验算 (34)4.6.2制动时不打滑按下式验算 (35)5 主梁的设计 (36)5.1主梁跨度的确定 (36)5.2主梁上钢轨的选择 (37)5.3主梁的合理强度设计 (38)5.3.1梁的强度条件 (38)5.3.2梁的截面选择 (39)5.3.3梁的合理截面形状 (40)5.3.4变截面梁与等强度梁 (40)5.3.5梁的合理受力 (41)5.4主梁合理刚度设计 (41)5.4.1梁的刚度条件 (42)5.4.2梁的合理刚度设计 (42)5.5箱形主梁的优化设计 (44)5.5.1桥式起重机箱形主梁的结构 (44)5.5.2优化的数学模型 (47)5.5.3主梁优化设计计算方法简述 (53)5.5.4结合本设计的主梁有关参数对主梁进行优化设计 (53)6 安全检验 (59)6.1机械部分的安全要求 (59)6.1.1减速器 (59)6.1.2大车运行机构 (59)6.1.3主梁的要求 (60)6.1.4高强度螺栓 (61)6.1.5电动机 (61)6.1.6焊接质量 (62)6.2电气设备检验 (62)6.2.1 电气设备要求 (62)6.2.2电气设备安装 (63)6.2.3供电及电路要求 (64)6.2.4对主要电气元件的安全要求 (66)6.2.5电气保护装置 (66)6.2.6照明、信号 (67)结论 (68)参考文献 (69)致谢 (70)1 绪论双梁桥式起重机在工程中有着广泛的应用，日益提高的各行业生产对承担企业生产线上主要物流任务的起重机的要求也越来越高。
10T桥式起重机设计
目录第一章绪论 ............................................ 错误！未定义书签。
1.1 选题的意义 ........................................ 错误！未定义书签。
1.2 本课题的研究目的 (2)1.3 桥式起重机的研究现状 (2)第二章设计方案 (4)2.1 起重机的介绍 42.2 起重机设计的总体方案 42.2.1 主梁的设计 (4)2.2.2 小车的设计 (4)2.2.3端梁的设计 (5)2.2.4桥架的设计 (5)第三章大车行车机构的设计 (6)3.1 设计的原则和要求63.1.1 机构传动方案 (6)3.1.2 大车行车机构布局 (6)3.2 搭车行车机构的计算73.2.1 确定结构的传动方案 (7)3.2.2 选择车轮与轨道并校核其强度 (7)3.2.3 运行组里的计算 (9)3.2.4 选择电动机 (10)3.2.5 计算发动机的发热功率 (11)3.2.6 减速器的选择 (11)3.2.7 验算运行速度与实际功率 (11)3.2.8 验算启动时间 (12)3.2.9 校核减速器功率 (13)3.2.10 验算不打滑条件 (13)3.2.11 选择制动器 (15)3.2.12 选择联轴器 (16)3.2.13 验算浮动轴 (17)3.2.14 缓冲器的选择 (18)第四章端梁的设计 (20)4.1 端梁尺寸的确定214.2 端梁的计算214.3主要焊缝的计算24第五章端梁结头的设计 (26)5.1 端梁接头的确定和计算 265.2 主要螺栓和焊缝的设计 29第六章桥架的结构设计 (31)6.1 桥架的结构形式316.2 桥架的结构设计与计算 31第七章焊接工艺设计 (39)致谢 (42)参考文献 (43)附录 (44)第一章绪论1.1 选题意义起重机械用来对物料作起重、运输、装卸和安装等作业的机械设备，它可以完成靠人力无法完成的物料搬运工作，减轻人们的体力劳动，提高劳动生产率，在工厂、矿山、车站、港口、建筑工地、仓库、水电站等多个领域部门中得到了广泛的使用，随着生产规模的日益扩大，特别是现代化、专业化的要求，各种专门用途的起重机相继产生，在许多重要的部门中，它不仅是生产过程中的辅助机械，而且已成为生产流水作业线上不可缺少的重要机械设备，它的发展对国民经济建设起着积极的促进作用。
50-10t双梁中轨箱型桥式起重机设计
优秀设计目录内容摘要 (1)关键词 (1)Abstract. (2)Key words (1)1.绪论 (3)1.1桥式起重机的介绍 (3)1.2桥式起重机设计的总体方案 (3)1.3主梁和桥架的设计 (3)1.4端梁的设计 (4)2.选型计算部分 (5)2.1主起升机构的设计 (5)2.2副起升机构的设计 (8)2.3小车运行机构 (12)2.4大车运行机构的设计 (16)3.结构计算部分 (22)3.1桥架尺寸的确定 (22)3.2主梁尺寸 (22)3.3主端梁界面 (23)3.4端梁截面尺寸的确定 (24)3.5主.端梁截面几何性质 (25)3.6载荷 (26)3.7扭转载荷 (29)3.8主梁的计算 (29)3.9端梁的计算 (39)3.10稳定性 (40)3.11总功率 (42)总结 (43)参考文献 (44)致谢 (45)内容摘要：这次毕业设计是针对毕业实习中桥式起重机所做的具体到吨位级别的设计。
随着我国制造业的发展，桥式起重机越来越多的应用到工业生产当中。
在工厂中搬运重物，机床上下件，装运工作吊装零部件，流水线上的定点工作等都要用到起重机。
起重机中种数量最多，在大小工厂之中均有应用的就是小吨位的起重机，小吨位的桥式起重机广泛的用于轻量工件的吊运，在我国机械工业中占有十分重要的地位。
但是，我国现在应用的各大起重机还是仿造国外落后技术制造出来的，而且已经在工厂内应用了多年，有些甚至还是七八十年代的产品，无论在质量上还是在功能上都满足不了日益增长的工业需求。
如何设计使其成本最低化，布置合理化，功能现代化是我们研究的课题。
本次设计就是对小吨位的桥式起重机进行设计，主要设计内容是50t/10t桥式起重机的结构及运行机构，其中包括桥架结构的布置计算及校核，主梁结构的计算及校核，端梁结构的计算及校核，主端梁连接以及大车运行机构零部件的选择及校核。
关键词：起重机大车运行机构桥架主端梁小吨位Abstract：The graduation project is a bridge crane for the graduation field work done by the tonnage level specific to the design. As China's manufacturing industry, more and more applications crane to which industrial production. Carry a heavy load in the factory, machine parts up and down, the work of lifting parts of shipment, assembly line work should be fixed on the crane is used. The largest number of species of cranes, both in the size of the factory into the application is small tonnage cranes, bridge cranes small tonnage of lightweight parts for a wide range of lifting, in China's machinery industry plays a very important position. However, our current application, or copy large crane behind the technology produced abroad, and has been applied in the factory for many years, and some 70 to 80 years of products, both in quality or functionality are not growing to meet the industrial demand. How to design it the lowest cost, rationalize the layout, function modernization is the subject of our study. This design is for small tonnage bridge crane design, the main design elements are 50t/10t crane structure and operation of institutions, including the bridge structure, calculation and checking the layout, the main beam structure calculation and checking , end beams calculation and checking, the main end beam connect and run the cart and checking body parts of choice.Key words：Crane The moving mainframe Bridge Main beam and end beam Small tonnage1.绪论1.1桥式起重机的介绍桥式起重机是桥架在高架轨道上运行的一种桥架型起重机，又称天车。
全套毕业设计十吨位桥式起重机大车运行机构设计[管理资料]
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编号无锡太湖学院毕业设计（论文）题目：十吨位桥式起重机大车运行机构设计信机系机械工程及自动化专业学号：0923087学生姓名：叶宏城指导教师：陈炎冬（职称：讲师）（职称：）2013年5月25日无锡太湖学院本科毕业设计（论文）诚信承诺书本人郑重声明：所呈交的毕业设计（论文）十吨位桥式起重机大车运行机构设计是本人在导师的指导下独立进行研究所取得的成果，其内容除了在毕业设计（论文）中特别加以标注引用，表示致谢的内容外，本毕业设计（论文）不包含任何其他个人、集体已发表或撰写的成果作品。
班级：机械92学号：0923087作者姓名：2013 年5 月25 日无锡太湖学院信机系机械工程及自动化专业毕业设计论文任务书一、题目及专题：1、题目十吨位桥式起重机大车运行机构设计２、专题二、课题来源及选题依据本次课程设计的课题来源于正常的生产实践需求。
选题的相关数据参数：起重机的起重量Q=10T，桥架跨度L=，大车运行速度Vdc=，工作类型为中级，机构运行持续率为JC%=25，起重机的估计重量G=168KN，小车的重量为Gxc=40KN，桥架采用箱形结构。
三、本设计（论文或其他）应达到的要求：1.了解桥式起重机的大车运行机构的相关知识和工作原理。
2.完成3张A0图纸（折合）。
3.撰写设计说明书，内容包括：课题的目的、意义、国内外动态；研究的主要内容；总体方案的拟定和主要参数的设计计算；传动方案的确定及设计计算，主要工作部件的设计；主要零件分析计算和校核；参考文献。
文字在30页左右，条理清楚，计算有据，格式按无锡太湖学院学士学位论文（设计）规范化要求。
四、接受任务学生：机械92 班姓名叶宏城五、开始及完成日期：自2012年11月12日至2013年5月25日六、设计（论文）指导（或顾问）：指导教师签名签名签名教研室主任〔学科组组长〕签名系主任签名2012年11月12日摘要桥式起重机是一种工作性能比较稳定，工作效率比较高的起重机。
10t桥式起重机设计说明书
目录目录 (I)序言 (1)第1章桥式起重机的概述 (2)1.1 桥式起重机分类及工作特点 (2)1.2 桥式起重机的用途 (4)1.3 桥式起重机的基本参数 (5)1.4 桥式起重机主要零部件 (7)1.4.1吊钩 (7)1.4.2钢丝绳 (8)1.4.3 滑轮和滑轮组 (10)1.4.4 滑轮组类型及选配原则 (11)1.5滑轮组及其滑轮组的倍率 (12)1.6 卷筒 (13)1.7 位置限位器 (13)1.8 缓冲器 (14)1.9桥式起重机发展概述 (15)1.9.1 国内桥式起重机发展动向 (15)第2章大车运行机构的设计 (18)2.1大车运行结构设计的基本思路及要求 (18)2.2 大车运行机构传动方案的确定 (18)2.3 大车运行机构具体布置时要注意的问题 (19)2.4 大车运行机构的设计计算 (19)2.4.1 大车运行结构的传动方案 (20)2.5轮压计算及强度验算 (21)2.5.1计算大车的最大轮压和最小轮压： (21)2.5.2 强度计算及校核 (22)2.6 运行阻力计算 (24)2.7 选择电动机 (25)2.8 减速器的选择 (26)2.9 验算运行速度及实际功率 (27)2.10 验算启动时间 (27)2.11 起动工况下校核减速器功率 (29)2.12 验算起动不打滑条件 (29)2.13 选择制动器 (32)2.14 选择联轴器 (33)2.15 低速浮动轴的验算 (33)2.16 缓冲器的选择 (35)第3章起升小车的计算 (37)3.1 确定机构的传动方案 (37)3.2小车运行机构的计算 (38)3.3选择车轮与轨道并验算起强度 (38)3.4运行阻力计算 (40)3.5 选电动机 (41)3.6 验算电动机发热条件 (42)3.7 选择减速器 (42)3.8 验算运行速度和实际所需功率 (43)3.9验算起动时间 (43)3.10 按起动工况校核减速器功率 (44)3.11 验算起动不打滑条件 (45)3.12 选择制动器 (46)3.13 选择高速轴联轴器及制动轮 (47)3.14 验算低速浮动轴强度 (48)3.15 起升机构的设计参数 (49)3.16 钢丝绳的选择 (50)3.17 滑轮、卷筒的计算 (52)3.18 根据静功率初选电动机 (53)3.19 减速器的选择 (54)3.20 制动器的选择 (55)3.21 启动时间及启动平均加速度的验算 (55)3.22 联轴器的选择 (56)第4章桥架结构的设计 (58)4.1 桥架的结构形式 (58)4.1.1 箱形双梁桥架的构成 (58)4.1.2 箱形双梁桥架的选材 (58)4.2 桥架结构的设计计算 (59)4.2.1 主要尺寸的确定 (59)4.2.2 主梁的计算 (61)4.3 端梁的计算 (67)4.4 端梁的尺寸的确定 (71)4.4.1 端梁总体的尺寸 (71)4.4.2端梁的截面尺寸 (71)第5章端梁接头的设计 (73)5.1 端梁接头的确定及计算 (73)5.1.1 腹板和下盖板螺栓受力计算 (74)5.1.2 上盖板和腹板角钢的连接焊缝受力计算 (75)5.2 计算螺栓和焊缝的强度 (76)5.2.1 螺栓的强度校核 (76)5.2.2 焊缝的强度校核 (77)第6章焊接工艺设计 (79)参考文献 (82)致谢 (83)序言桥式起重机是横架于车间和料场上空进行物料调运的起重设备。
5010T,跨度28m,双粱桥式起重机结构设计
50/10T,跨度28m,双粱桥式起重机结构设计1)大车轴距2)腹板尺寸3)翼缘板尺寸4)主梁尺寸第二章总体设计1.桥架尺寸的确定B=（11~46）L=（11~46）⨯22.5=6.375~4.25 m根据小车轨距和中轨箱型梁宽度以及大车运行机构的设置，取B=5 m端梁全长B=5.916m2.主梁尺寸高度h=（11~1417）L=1821~1500 mm取腹板高度h=1600 mm腹板厚度1δ=6 mm翼缘板厚度δ=24 mm主梁总高度1H=h+2δ=1648 mm主梁宽度 b=(0.4~0.5)1H=648~810 mm字腹板外侧间距 b=760 mm>60L=425 mm 且>13H=540 mm上下翼缘板相同为24 mm⨯600 mm主梁端部变截面长取 d=2350 mm.图2-1 双梁桥架结构第三章主端梁截面积几何性质B=5 mB=5.916mh=1600 mm1δ=6 mmδ=24 mm1H=1648 mmB1=b=552 mm24 mm⨯600 mmd=2350 mm1）截面尺寸1) 固定载荷图3-1 主梁与端梁截面a) 主梁截面A=(600⨯24+1600⨯6)⨯2=0.04512m2惯性矩xI=2.8164160.425436160⨯⨯⨯+⨯）（=2.13053⨯1010 mm4yI=2.250491616033454⨯⨯⨯+⨯）（=1.71202⨯109 mm4b)端梁截面A=2876020600⨯⨯+⨯）（=36160 mm2=0.03616m2xI=762802603.876⨯⨯⨯+⨯）（=4.2641⨯109 mm4yI=60237.6760.83632⨯+⨯⨯⨯（）=6.8221⨯108 mm4第四章载荷主梁自重载荷'F =kρAg⨯9.81=1.281.9104512.07850⨯⨯⨯⨯=4165.3 NA=0.04512m2xI=2.130⨯1010 mm4yI=1.712⨯109 mm4A1=0.03616m2xI1=4.264⨯109 mm4yI1=6.822⨯108 mm4'F=4165.3 N5.3.1 验算主腹板受拉翼缘板焊缝④的疲劳强度max σ=20()x xM y I δ-=3103207438.87108002.130510⨯⨯⨯=120.43MPamin σ=min 20()xM y I δ-=31076171.8108002.130510⨯⨯⨯ =28.84MPa图5-5 主梁截面疲劳强度验算点应力循环特性γ=min max σσ=28.84120.43=0.2395〉0 根据工作级别A6，应力集中等级1K 及材料Q235，查得119][1=-σMP ，b σ=370 MPa焊缝拉伸疲劳需用应力为max σ=120.43MPamin σ=28.84MPa012主梁加劲肋设置及稳定性计算.专业.专注..专业.专注..专业.专注..专业.专注..专业.专注.=81.40 MPa <[]σ∏=175 MPa翼缘板对中轴的静矩为yS=8⨯600⨯390=1569920 mm3τ= 22v yxF SIδ=8103215.2215699203601299⨯⨯⨯⨯=15.07 MPa折算应力为σ=223στ+=2281.40315.07+⨯=87.8 MPa<[]σ∏=175 MP截面3-3及4-4端梁支承处两个截面很近，只计算受力稍大的4-4端梁支承处为安装大车轮角轴承箱座而切成缺口并焊上两块弯板（20 mm⨯185 mm）,端部腹板两边都采用双面贴角焊缝，取fh=8 mm,支承处高度314 mm，弯板两个垂直面上都焊有车轮组定位垫板（16 mm⨯90 mm⨯340 mm）,弯板参与端梁承载工作，支承处截面（3-3及4-4）如图所示6-3图6-3 端梁支承处截面形心1y=i iA yA∑=20600428378197214130393860028378214130⨯⨯+⨯⨯⨯+⨯⨯⨯⨯+⨯⨯+⨯⨯=199.6 mm惯性矩为xI=3.4296⨯108 mm4.专业.专注..专业.专注..专业.专注..专业.专注..专业.专注.1）桥架的垂直静刚度第七章主梁和端梁的连接主、端梁采用连接板贴角焊缝连接，主梁两侧各用一块连接板与主、端梁的腹板焊接，连接板厚度δ=8 mm，高度1h=0.95dh=0.95⨯800=755 mm,取1h=750 mm，主梁腹板与端梁腹板之间留有20~50的间隙，在组装桥架时用来调整跨度。
大车运行机构的计算
电动双梁桥式起重机的设计题目：设计计算某机械加工车间使用的电动双梁吊钩桥式起重机包括大车运行机构，桥架，小车运行机构及起升机构。
已知数据：起重量主起升50t，副起升10t；起升高度主起升12m，副起升14m；工作速度主起升6.2m/min，副起升12.5m/min；桥架采用箱形梁式结构，桥架跨度28.5m；大车运行速度85.9m/min；小车运行速度38.5m/min；工作级别A5；机构接电持续率JC%=25%；起重机估计总重（包括小车重量）G=53.6t，小车自重11921kg；大车运行机构采用分别式驱动方式。
大车运行机构计算.1.1 确定传动机构方案跨度为28.5m,为减轻重量，决定采用分别传动的大车运行机构的布置方式，如图所示：图2-1分别传动的大车运行机构布置方式1-电动机；2-制动器；3-带制动轮的半齿连轴器；4-浮动轴；5-半齿连轴器；6-减速器；7-车轮；8-全齿轮连轴器1.2 选择车轮与轨道，并验算其强度按照图1—2所式的重量分布，计算大车车轮的最大轮压和最小轮压：图2-2轮压计算图满载时，最大轮压：Pmax=(G-Gxc)/4+(Q+Gxc)(L-e)/2L (2.1) =(536-119.21)/4+(50+11.921)(28.5-2)/(2⨯28.5)=392.08KN空载时，最小轮压：Pmin=(G-Gxc)/4+Gxc/2L (2.2) =(536-119.21)/4+119.21/(2⨯28.5)=106.29KN车轮踏面疲劳计算载荷：Pc =(2Pmax+Pmin)/3 (2.3) =(2⨯329.08+106.29)/3=296.82KN车轮材料：采用ZG340-640（调质），σb=700MPa,σs=380MPa,由[3]附表18选择车轮直径Dc=800mm,由[3]表5-1查得轨道型号为Qu70按车轮与轨道为点接触和线接触两种情况来验算车轮的接触强度点接触局部挤压强度验算：Pc"=k2 *R2*c1*c2/m3(2.4)=0.181⨯4002⨯0.99⨯1/(0.3883) =490931.51N式中 k2—许用点接触应力常数（N/mm2），由[3]表5—2查得k2=0.181。
5010t双梁桥式起重机大车运行机构与主梁的设计论文
本科毕业设计（论文）50/10t双梁桥式起重机大车运行机构与主梁设计摘要起重机可以提高了人们的劳动效率，搬动大型物件。
在厂房搬运大型零件或重型装置，桥式起重机是不可或缺的运输工具。
随着现代科学技术的迅速发展，工业生产规模的扩大和自动化程度的提高，起重机在现代化生产过程中应用越来越广，作用愈来愈大，对起重机的要求也越来越高。
尤其是计算机技术的广泛应用，许多跨学科的先进设计方法出现，促使起重机的技术进入崭新的发展阶段。
本文结合生产实际，提出了双梁起重机大车运行机构以与主梁的几种方案，通过分析确定了最终方案，对大车运行机构与主梁进行了设计，对起重机的安全检查提出了要求。
关键词：双梁桥式起重机；大车运行机构；主梁；设计ABSTRACTthe hoist crane's appearance raised people's labor efficiency greatly, before need many people the large-scale thing which spends the long time to be able to move can achieve the effect easily now with the hoist crane, particularly in the small scope moves in the process hoist crane's function is quite obvious. Transports the large-scale components or the heavy installment bridge-type hoist crane in the factory workshop may not attain lacks.along with the modern science technology's rapidly expand, the industrial production scale's expansion and automaticity's enhancement, the hoist crane applies in the modernization production process is getting more and more broad, the function is getting bigger and bigger, is also getting higher and higher to hoist crane's request. Especially computer technology's widespread application, many interdiscipline's advanced design methods appear, these urge hoist crane's technology to enter the brand-new development phase.the in coor with progress of production proposed actually the hoist crane large cart movement organization as well as king post's several kind of plans, have carried on the design notes through the analysis designation plan and to the large cart movement organization and the king post, simultaneously, also set the request to hoist crane's security check.Keywords: Double beam bridge type hoist crane; Large cart movement organization; King post; Designs目录摘要IABSTRACT (II)1 绪论12 大车运行机构方案拟订以与选择52.1大车运行机构的几种常用方案52.1.1低速集中驱动52.1.2中速集中驱动62.1.3高速集中驱动62.1.4分别驱动72.2大车运行机构方案分析72.2.1低速集中驱动82.2.2中速集中驱动82.2.3高速集中驱动82.3大车运行机构方案选择83 主梁方案的拟订与选择93.1主梁常用的几种方案93.1.1工字钢主梁93.1.2桁架主梁93.1.3箱形主梁93.2主梁方案分析113.2.1工字钢主梁113.2.2桁架主梁113.2.3箱形主梁113.3主梁方案选择114 大车运行机构的设计144.1运行阻力的计算144.1.1摩擦阻力144.1.2坡道阻力174.1.3风阻力174.2电动机的选择194.2.1概述194.2.2电动机静功率194.2.3电动机初选194.2.4电动机过载校验204.2.5电动机发热校验214.2.6起动时间与起动平均加速度校验224.2.7选择合适的电动机型号234.3减速器的选择234.3.1概述234.3.2减速器型号的选择244.4制动器的选择244.4.1制动器概述244.4.2制动器相关参数的计算264.4.3制动器型号的选择274.5联轴器的选择274.6运行打滑验算284.6.1起动时不打滑按下式验算：284.6.2制动时不打滑按下式验算：285 主梁的设计305.1主梁跨度的确定315.2主梁上钢轨的选择315.3主梁的合理强度设计335.3.1梁的强度条件335.3.2梁的合理截面形状355.3.3变截面梁与等强度梁355.3.4梁的合理受力365.4主梁合理刚度设计365.4.1梁的刚度条件365.4.2梁的合理刚度设计375.4.3梁的合理加强375.4.4梁的的跨度选取385.4.5合理安排梁的约束与加载方式386 安全检验396.1机械部分的安全要求396.1.1减速器396.1.2大车运行机构396.1.3主梁的要求416.1.4高强度螺栓426.1.5电动机426.1.6重要构件材质426.1.7焊接质量检测426.2电气设备检验426.2.1电气设备符合GB/T14406和产品图样的要求436.2.2电气设备安装436.2.3供电与电路要求446.2.4对主要电气元件的安全要求466.2.5电气保护装置466.2.6照明、信号47结论51参考文献50致511 绪论桥式起重机在冶金、矿山等行业被大量使用，尤其是电动双梁桥式起重机，凭借着其优越的起重性能、广阔的生产适用围和强大的负载能力以与其工作的稳定性在各个行业中更是有着广泛的运用。
桥式起重机电气控制毕业设计方案
10T/50桥式起重机电气控制设计摘要桥式起重机是桥架在高架轨道上运行的一种桥架型起重机，又称天车。
桥式起重机的桥架沿铺设在两侧高架上的轨道纵向运行，起重小车沿铺设在桥架上的轨道横向运行，构成一矩形的工作范围，就可以充分利用桥架下面的空间吊运物料，不受地面设备的阻碍。
桥式起重机广泛地应用在室内外仓库、厂房、码头和露天贮料场等处。
桥式起重机可分为普通桥式起重机、简易粱桥式起重机和冶金专用桥式起重机三种。
普通桥式起重机一般由起重小车、桥架运行机构、桥架金属结构组成。
起重小车又由起升机构、小车运行机构和小车架三部分组成。
起升机构包括电动机、制动器、减速器、卷筒和滑轮组。
电动机通过减速器，带动卷筒转动，使钢丝绳绕上卷筒或从卷筒放下，以升降重物。
本文重点研究起重机的控制，通过使用串电阻的调速方法已实现对电机的控制，从而控制起重机。
关键词：起重小车。
电动机；串电阻调速10T/50 bridge crane electrical control designABSTRACTBridge crane is a bridge in an elevated running track as a bridge-type crane, also known as Crane。
Bridge crane installed in the bridge along the track on both sides of the elevated vertical run，Lifting trolley along the bridge on the laying of the track in the horizontal run, which constitute the scope of work of a rectangle, you can take full advantage of the space bridge was being lifted the following materials, the hindered from ground equipment.Bridge crane widely used in indoor and outdoor warehouses, factories, docks and outdoor storage yard, etc.Bridge crane bridge crane can be divided into ordinary, simple beam bridge crane and metallurgical three special bridge crane.Lifting bodies, including the motor, brake, reducer, drum and pulley blocks。
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1绪论·······························································1.1 桥式起重机的介绍·············································1.2 桥式起重机设计的总体方案·····································1.2.1主梁和桥架的设计··············································1.2.2端梁的设计····················································2 小车机构的设计···············································2.1 小车主起升机构的计算·······································2.1.1确定机构传动方案··············································2.1.2小车车轮与轨道的选择及其强度校核······························2.1.3运行阻力运算··················································2.1.4选择电动机····················································2.1.5验算电动机的发热条件··········································2.1.6减速器的选择··················································2.1.7验算运行速度和实际所需功率···································2.1.8验算起动时间··················································2.1.9起动工况下校核减速器功率······································2.1.10验算启动不打滑条件···········································2.1.11选择制动器··················································2.1.12选择联轴器··················································2.1.13浮动轴的验算················································2.1.14缓冲器的选择················································2.2 小车副起升机构的计算·······································2.2.1确定机构传动方案··············································2.2.2小车车轮与轨道的选择及其强度校核······························2.2.3运行阻力运算··················································2.2.4选择电动机····················································2.2.5验算电动机的发热条件··········································2.2.6减速器的选择··················································2.2.7验算运行速度和实际所需功率···································2.2.8验算起动时间··················································2.2.9起动工况下校核减速器功率······································2.2.10验算启动不打滑条件···········································2.2.11选择制动器··················································2.2.12选择联轴器··················································2.2.13浮动轴的验算················································2.3 小车运行机构方案···············································2.3.1 小车运行机构设计2.3.2 确定小车轨距和小车轮距3 大车运行机构的设计···············································3.1 设计的基本原则和要求·········································3.1.1机构传动方案··················································3.1.2大车运行机构具体布置的主要问题································3.2 大车运行机构的计算·········································3.2.1确定机构传动方案··············································3.2.2大车车轮与轨道的选择及其强度校核······························3.2.3运行阻力运算··················································3.2.4选择电动机····················································3.2.5验算电动机的发热条件··········································3.2.6减速器的选择··················································3.2.7验算运行速度和实际所需功率···································3.2.8验算起动时间··················································3.2.9起动工况下校核减速器功率······································3.2.10验算启动不打滑条件···········································3.2.11选择制动器··················································3.2.12选择联轴器··················································3.2.13浮动轴的验算················································3.2.14缓冲器的选择················································4 大梁桥架和端梁的设计与计算······································4.1 桥架主要尺寸的确定········································4.1.1大车轮距·····················································4.1.2主梁高度·····················································4.1.3端梁高度·····················································4.1.4桥架端部梯形高度·············································4.1.5主梁腹板高度·················································4.1.6确定主梁截面尺寸·············································4.1.7加劲板的布置尺寸·············································4.2 主梁的计算··················································4.2.1计算载荷确定·················································4.2.3主梁水平最大弯矩·············································4.2.4主梁的强度验算···············································4.2.5主梁的垂直刚度验算···········································4.2.6主梁的水平刚度验算···········································4.3 端梁的计算··············································4.3.1计算载荷的确定···············································4.3.2端梁垂直最大弯矩·············································4.3.3梁的水平弯矩·················································4.3.4端梁截面尺寸的确定···········································4.3.5端梁的强度验算···············································4.4 主要焊缝的计算··············································4.4.1端梁端部上翼缘焊缝···········································4.4.2端梁端部下翼缘焊缝···········································4.4.3主梁与端梁的连接焊缝·········································4.4.4主梁上盖板焊缝···············································结束语······················································参考文献·······················································致谢···················································第一章绪论1.1 桥式起重机的介绍桥式起重机是桥架在高架轨道上运行的一种桥架型起重机，又称天车。