小型農(nóng)田起重機(jī)設(shè)計(jì),小型農(nóng)田起重機(jī)設(shè)計(jì),小型,農(nóng)田,起重機(jī),設(shè)計(jì) 附錄1：外文翻譯 為了更準(zhǔn)確地了解汽車(chē)起重機(jī)抗傾覆穩(wěn)定性的可靠性，在以總體關(guān)鍵參數(shù)為設(shè)計(jì)變量的動(dòng)態(tài)軟件環(huán)境中建立了參數(shù)化多體動(dòng)力學(xué)模型。在此基礎(chǔ)上，根據(jù)工作條件和起重機(jī)動(dòng)力學(xué)仿真結(jié)果，建立了該車(chē)起重機(jī)的穩(wěn)定性判據(jù)。對(duì)影響汽車(chē)起重機(jī)穩(wěn)定性的設(shè)計(jì)變量，采用截?cái)嗾龖B(tài)分布抽樣法，采用蒙特卡羅方法對(duì)其可靠性進(jìn)行了分析。結(jié)果表明，在最危險(xiǎn)工況下，汽車(chē)起重機(jī)的穩(wěn)定性可靠度為0.9998。分析表明，采用現(xiàn)代多體動(dòng)力學(xué)和蒙特卡羅方法對(duì)汽車(chē)起重機(jī)抗傾覆穩(wěn)定性進(jìn)行可靠度計(jì)算是可行的，其計(jì)算結(jié)果比傳統(tǒng)安全系數(shù)法更準(zhǔn)確。 大型數(shù)控機(jī)床恒流量閉式靜壓轉(zhuǎn)臺(tái)的變形，由于其直徑大、承載能力強(qiáng)，對(duì)膜厚有很大的影響。根據(jù)彈性圓板變形理論，推導(dǎo)了在不同位置承受均布力的簡(jiǎn)支條件下工作臺(tái)變形的微分方程。給出了工作臺(tái)的位移曲線(xiàn)。發(fā)現(xiàn)了靜壓轉(zhuǎn)臺(tái)的受力和變形缺陷，為支持重型工件加工的定位和油膜是否失效提供了理論依據(jù)。 計(jì)算了汽車(chē)制動(dòng)系統(tǒng)的設(shè)計(jì)，并根據(jù)已知的汽車(chē)相關(guān)參數(shù)進(jìn)行了主要參數(shù)的計(jì)算。研究了制動(dòng)制動(dòng)力矩、制動(dòng)力矩和制動(dòng)力分配系數(shù)以及液壓制動(dòng)驅(qū)動(dòng)機(jī)構(gòu)的相關(guān)參數(shù)。最后對(duì)制動(dòng)性能進(jìn)行了詳細(xì)的分析。 研制了一套渦流檢測(cè)與自動(dòng)分離系統(tǒng)，對(duì)HFW管道中的焊縫缺陷進(jìn)行檢測(cè)，并對(duì)缺陷管進(jìn)行分離。應(yīng)用相敏檢測(cè)器，通過(guò)低通濾波器獲得焊縫缺陷的純信號(hào)。將焊縫缺陷信號(hào)信息、飛鋸位移信息和焊管焊接速度信息融合在一起。建立了缺陷焊管非定長(zhǎng)截?cái)嗟臄?shù)學(xué)模型。設(shè)計(jì)了一種自動(dòng)分離系統(tǒng)，用于切割和分離生產(chǎn)線(xiàn)中有缺陷的焊管。 對(duì)空氣流動(dòng)及其模型的研究主要集中在設(shè)計(jì)雙層蓋屋頂，建議在潮濕的建筑物中使用。軟件ansys采用CFD方法進(jìn)行建模。通風(fēng)雙層屋頂設(shè)計(jì)的首要問(wèn)題是選擇最佳的空氣腔厚度。 根據(jù)選定的模型，在閣樓外緣的1.76米和4.23米之間有一個(gè)盲點(diǎn)，空氣倒流發(fā)生在上屋頂甲板的底面上，導(dǎo)致通風(fēng)腔通風(fēng)不良。曲軸的動(dòng)強(qiáng)度分析是結(jié)構(gòu)設(shè)計(jì)的基礎(chǔ)。本文討論了用亞當(dāng)斯軟件進(jìn)行動(dòng)態(tài)仿真的方法，同時(shí)對(duì)簡(jiǎn)支梁、連續(xù)梁模型、單拐模型和整體接觸模型三種傳統(tǒng)的應(yīng)力分析方法進(jìn)行了比較。提出了一種新的計(jì)算方法：首先用雷諾茲方程建立油膜模型，得到油膜剛度，然后將其等效為彈簧沖擊軸頸的等效剛度，最后建立整個(gè)曲軸的有限元模型。該模型能更準(zhǔn)確地反映曲軸的實(shí)際情況，可用于曲軸的優(yōu)化設(shè)計(jì)。雙交叉步降應(yīng)力加速壽命試驗(yàn)（dcsds-alt）本文采用開(kāi)關(guān)下雙應(yīng)力交替。與恒應(yīng)力試驗(yàn)相比，階梯應(yīng)力試驗(yàn)減少了試件數(shù)量、時(shí)間和成本，最終提高了加速試驗(yàn)的效率。對(duì)于氣動(dòng)缸，應(yīng)力測(cè)試失效物理可以描述為累積退化模型。利用累積損傷一般對(duì)數(shù)線(xiàn)性關(guān)系和威布爾假設(shè)，在恒定應(yīng)力測(cè)試下，將失效數(shù)據(jù)等效轉(zhuǎn)化為失效數(shù)據(jù)。然后，可以更準(zhǔn)確地導(dǎo)出可靠性規(guī)范。平均壽命估計(jì)誤差的5%和特征壽命誤差的1.85%對(duì)氣動(dòng)工業(yè)壽命預(yù)測(cè)非常滿(mǎn)意。本文研究了sc50c液壓履帶式起重機(jī)13米基本臂，使靜態(tài)分析起重機(jī)基本臂采用ANSYS軟件，得到應(yīng)力分布。根據(jù)起重機(jī)基本臂架的載荷和結(jié)構(gòu)特點(diǎn)，建立了起重機(jī)臂架的有限元模型，為起重機(jī)臂架的設(shè)計(jì)和優(yōu)化提供參考。 一個(gè)完整的液壓系統(tǒng)由五個(gè)部分組成，即動(dòng)力元件、控制元件、輔助元件和液壓油的實(shí)現(xiàn)。原動(dòng)力流體在動(dòng)力元件中的作用轉(zhuǎn)化為機(jī)械能的壓力，即液壓系統(tǒng)的泵，它是驅(qū)動(dòng)整個(gè)液壓系統(tǒng)的動(dòng)力。液壓泵齒輪的結(jié)構(gòu)形式一般為泵、葉片泵和活塞泵。實(shí)現(xiàn)元件(如液壓缸和液壓馬達(dá))，即液體的壓力可以轉(zhuǎn)化為機(jī)械能，以驅(qū)動(dòng)負(fù)荷直線(xiàn)往復(fù)運(yùn)動(dòng)或旋轉(zhuǎn)運(yùn)動(dòng)。控制元件(即各種液壓閥)在液壓系統(tǒng)中控制和調(diào)節(jié)液體壓力、流量和方向。根據(jù)控制功能的不同，將液壓控制閥分為閥門(mén)、流量控制閥和方向控制閥。壓力控制閥分為效益流量閥(安全閥)、減壓閥、順序閥、壓力繼電器等；流量控制閥包括節(jié)流閥、調(diào)節(jié)閥、分流閥組等；方向控制閥包括單向閥、單向流體控制閥、穿梭閥、閥等。在控制方式不同的情況下，可分為液壓閥控制開(kāi)關(guān)閥、控制閥和設(shè)定比值控制閥。輔助部件，包括油箱、濾油器、油管和管接頭、密封件、壓力表、油位、油元等。液壓油是液壓系統(tǒng)中的工作能量傳遞介質(zhì)，有各種礦物油、乳化油液壓成型霍普類(lèi)。液壓系統(tǒng)的作用是幫助人類(lèi)工作。主要是通過(guò)實(shí)現(xiàn)元件的旋轉(zhuǎn)或壓力成往復(fù)運(yùn)動(dòng)。液壓系統(tǒng)和液壓功率控制信號(hào)由兩部分組成，信號(hào)控制部分采用液壓部分驅(qū)動(dòng)控制閥運(yùn)動(dòng)。部分液壓功率是指用電路圖來(lái)表示不同功能的元件之間的相互關(guān)系。含液壓泵源、液壓馬達(dá)及輔助元件；液壓控制部分包含各種控制閥，用于控制油液流量、壓力和方向；操作或液壓缸與液壓馬達(dá)配合，根據(jù)實(shí)際需要自行選擇。 附錄2：外文原文 To more accurately learn reliability on anti-overturning stability for a truck crane, a parametric muti-body dynamics model is built in a dynamic software environment with overall key parameters as design variables. On this basis, stability criteria of this truck crane are established according to the working conditions and crane dynamics simulation results. After a truncated normal distribution sampling method is given for design variables which will effect on truck crane’s stability, the reliability analysis of this truck crane is done via Monte Carlo method. The result indicates that the truck crane’s stability reliability is 0.9998 in the most dangerous working condition. Analysis shows that the reliability calculation of truck crane anti-overturning stability is feasible using modern muti-body dynamics and Monte Carlo method, and the results are more accurate than conventional safety factor method.The deformation of constant flow and closed type hydrostatic rotary table of heavy duty CNC machine tool has a great influence on the film thickness because of its large diameter, high load-bearing. According to the circular plate deformation theory of elasticity, differential equations of worktable deformation are derived in the simply supported conditions when bearing uniform force of different locations. Displacement curves of worktable are obtained. Force and deformation weaknesses of hydrostatic rotary table are found, which can provide theory basis for supporting location of heavy workpiece machining and whether oil film is failure or not. Calculation of car brake system design, also according to the known automotive related parameters is obtained by calculating the main parameters. The brake and braking torque, braking moment and braking force distribution coefficient and hydraulic brake drive mechanism related parameters. Finally, the braking performances are analyzed in detail. An eddy current detection and automatic separating system is developed to defect the weld defects in HFW pipe and separate the defective pipe. Application of phase sensitive detector, the pure signal of the weld defect is obtained through a low-pass filter. The information of the weld defect signal, the displacement of flying saw and the welding speed of welded pipe are fused together. The mathematical model is established for unfixed length truncation of the defective welded pipe. An automatic separating system is designed to cut and separate the defective welded pipes in the production line. The study of air flow and its modelling is particularly focused on designing double-cladding roofs, which are recommended for buildings in wet conditions. Software ANSYS [, which uses CFD method, is used for the modelling. The primary issue concerning the design of ventilated double-cladding roofs is to select the optimum thickness of air cavity. Based on the selected model, there is a blind spot in between 1.76 m and 4.23 m of the outer edge of the attic where air back flow occurs at the bottom surface of the upper roof deck which leads to poor ventilation of the ventilated cavity. Dynamic and strength analysis of crankshaft is the basis of structural design. The paper discussed the dynamic simulation method using software of ADAMS, at same time compared the three traditional stress analysis methods: simply supported beam or continuous beam model, single crank model and overall contact model. A new method was proposed, firstly to establish the oil film model with Reynolds equation and obtain the oil film stiffness, then to treat it as the equivalent stiffness of spring impacting on shaft neck, lastly to create the finite element model of the whole crankshaft. The model will be more precisely reflect the real conditions and can be use to the optimization of crankshaft. Double Crossed Step-Down-Stress Accelerated Life Testing (DCSDS-ALT) discussed in this paper was implemented by switch down the double stresses alternately. Compared to constant stress test, step-stress test decreased specimen numbers, time and cost, and eventually well improve the accelerated testing efficiency. For pneumatic cylinder, the step-down-stress testing failure physics can be described as cumulative degradation model. By use of cumulative damage General Log-Linear relationship and Weibu ll assumption, the failure data obtained were equivalently converted to failure data under constant stress testing. Then the reliability specifications can be derived with better accuracy. The 5% of average lifetime estimation error and 1.85% of the characteristic lifetime error are very satisfying for pneumatic industrial lifetime prediction. This article studied the 13 m basic boom of SC50C hydraulic crawler crane, and made static analysis on crane basic boom by applying ANSYS, and obtains the stress distribution. Based on the features of the loads and structure of the crane basic boom, this paper sets up a finite element model of it, thus providing reference for the design and optimization of crane boom. A complete hydraulic system consists of five parts, namely, power components, the implementation of co- mponents, control components, auxiliary components and hydraulic oil. The role of dynamic components of the original motive fluid into mechanical energy to the pressure that the hydraulic system of pumps, it is to power the entire hydraulic system. The structure of the form of hydra- ulic pump gears are generally pump, vane pump and piston pump. Implementation of components (such as hydraulic cylinders and hydraulic motors) which is the pressure of the liquid can be converted to mechanical energy to drive the load for a straight line reciprocating movement or rotational movement. Control components (that is, the various hydraulic valves) in the hydraulic system to control and regulate the pressure of liquid, flow rate and direction. According to the different control functions, hydraulic pressure control valve can be divided into valves, flow control valves and directional control valve. Pressure control valves are divided into benefits flow valve (safety valve), pressure relief valve, sequence valve, pressure relays, etc.; flow control valves including throttle, adjusting the valves, flow diversion valve sets, etc.; directional control valve includes a one-way valve , one-way fluid control valve, shuttle valve, valve and so on. Under the control of different ways, can be divided into the hydraulic valve control switch valve, control valve and set the value of the ratio control valve. Auxiliary components, including fuel tanks, oil filters, tubing and pipe joints, seals, pressure gauge, oil level, such as oil dollars. Hydraulic oil in the hydraulic system is the work of the energy transfer medium, there are a variety of mineral oil, emulsion oil hydraulic molding Hop categories.The role of the hydraulic system is to help humanity work. Mainly by the implementation of components to rotate or pressure into a reciprocating motion. Hydraulic system and hydraulic power control signal is composed of two parts, the signal control of some parts of the hydraulic power used to drive the control valve movement. Part of the hydraulic power means that the circuit diagram used to show the different functions of the interrelationship between components. Containing the source of hydraulic pump, hydraulic motor and auxiliary components; hydraulic control part contains a variety of control valves, used to control the flow of oil, pressure and direction; operative or hydraulic cylinder with hydraulic motors, according to the actual requirements of their choice.