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毕业设计论文任务书任务书1. 毕业设计(论文)题目: 液压动力滑台(用于精镗)2. 毕业设计(论文)使用的原始资料(数据)及设计技术要求工作面宽 B=250mm; 行程 250mm进给力 10000N滑台快进速度 10m/min最小进给量 25mm/min推荐值: 油缸内径/活塞杆直径 63mm/45mm 油泵流量 16l/min滑台自动循环: 快进工进死铁停留快退原位停止3. 毕业设计(论文)工作内容及完成时间撰写开题报告 1周液压系统、滑台受力分析及结构设计 5周装配图及零件图绘制 4周外文翻译及设计说明书 2周注: 图纸总量零号图纸33.5张翻译时实词不少于4000字4. 参考资料沈阳工业大学主编.组合机床设计.上海科技出版社,1985.9,第一版金振华.组合机床及其调整与使用.机械工业出版社,1990,第一版东南大学章宏甲.液压与气压传动.机械工业出版社,2000.5,第一版贾铭新.液压传动与控制.国防工业出版社,2000.1,第二版姚永明.非标准设备设计手册.上海交通大学出版社,1999.12,第一版手册组.机床设计手册.机械工业出版社,1986.12,第一版 金属切削机床(组合机床设计及机床自动控制).南京航空学院, 1975.5 Richard P.Paul Manipulators: Machematics Programming and control, MIT Press, 1981. 1液压动力滑台（用于精镗）的设计姓名：赵蓓蓓 班级：990316摘要该课题主要是研究液压系统及电器控制电路设计、相关液压元件的选用和图纸绘制。而液压系统的工作原理在本课题中主要通过液压滑台的动作循环来实现.液压动力滑台是液压动力组合机床最主要的通用部件之一，是完成刀架切削运动和进给运动的动力部件。它的质量以及控制原理直接关系到零件的加工质量。液压动力滑台由滑台、滑座、油缸三部分组成.油缸固定在滑座上，活塞杆则固定在滑台的下面。滑座和滑台配置山-矩形导轨。滑台在滑座上的移动，借助于液压站打出的压力油通入油缸前腔或后腔来实现的。滑台的工作速度则通过调整节流阀进行无级调速。滑台的各种工作循环由专门的液压系统配以相应的电气及液压挡铁来实现。该课题完成后可为组合机床提供平稳、可靠的进给运动动力部件，从而来保证零件的加工质量。关键词液压动力滑台 液压控制原理 切削运动 进给运动主要数据工作面宽 B=250mm; 行程 250mm进给力 10000N滑台快进速度 10m/min最小进给量 25mm/min 指导老师：The design of the hydraulic power sliding table(to be used for finish-boring)Name: Zhao Bei Bei Class: 990316ABSTRACTThis theme is mainly study hydraulic system and electric control electrocircuit design, the selection of the hydraulic components and the paper drawing .In this theme, the working principle of the hydraulic system is realized by the operation cycle of the hydraulic power sliding table. Hydraulic power sliding table is one of the most universal components of the modular machine tool. It can finish the cutting movement and feed movement of the tool post . Its quality and control theory have something to do with the working quality of the parts directly. Hydraulic power sliding table is composed of sliding table, saddle and oil cylinder. Oil cylinder is fixed on the saddle and piston rod is fixed under the sliding table. The sliding table and the saddle set up E-rectangular guide way. The removal of the sliding table is depended on which the pressure oil from the hydraulic station flows into the front space or the back space of the oil cylinder. The working speed of the sliding table carries on stepless speed changing through adjusting throttle valve. All kinds of the working circulation of the sliding table is finished by special hydraulic system setting up corresponding electric and hydraulic stopper. This theme supplies stable and reliable feed movement power component for the modular machine tool to assure the working quality of the parts.KEY WORDHydraulic power sliding table Hydraulic control theory Cutting movement Admission movement MAIN DATUMThe breadth of the Working face breath: B=250mm Stroke: 250mmFeed force: 10000N The lest depth of feed: 25mm/minThe rapid feed speed of the sliding table: 10m/minFaculty adviser: 目 录绪论1液压动力滑台有关备用数据的计算2第1章 液压缸的结构设计31.1 负载图及速度图31.2 初定液压缸的结构尺寸41.3 液压缸工况图5第2章 拟订液压回路92.1 选择液压回路9 2.2 组成液压系统图10第3章 计算和选择液压元件133.1 确定液压缸的规格和电机功率133.2 液压阀的选择143.3 确定管道尺寸153.4 确定油箱容量15第4章 液压系统主要性能的估算164.1 液压缸的速度164.2 系统的效率164.3 液压系统发热与温升的验算22第5章 导轨的设计计算与检验245.1 导轨的设计计算245.2 导轨许用比压值的算255.3 导轨面比压的计算25结束语30个人心得31谢词32参考文献33附录34译文资料34资料译文49绪论液压传动相对于机械传动来说是一门新技术。近代液压传动在工业上的真正推广使用只是本世纪中叶以后的事，至于它和微电子技术密切结合，得以在尽可能的空间内传递出尽可能大的功率并加以精确控制，更是近十年内出现的新事物。当前，液压技术在实现高压、高速、大功率、高效率、低噪音、经久耐用、高度集成化等各项要求都取得了重大的进展，在完善比例控制、伺服控制、数字控制等技术上也有许多新成就。此外，在液压元件和液压系统的辅助设计、计算机仿真和优化以及微机控制等开发性工作方面，更日益显示出显著的成绩。我国的液压工业开始于本世纪50世纪。60年代开始进行自行设计。从80年代起，我国加速了对西方先进液压产品和技术的有计划引进、消化、吸收和国产化工作，使得我国的液压技术在产品质量、经济效益、人才培训、研究开发等各个方面取得长足的发展。 由于液压技术广泛地应用了高技术成果，如自动控制技术、计算机技术、微电子技术、摩擦磨损技术、可靠性技术以及新工艺、新材料的应用，使系统的液压技术有了新的发展，也使液压系统和元件水平有了很大提高。但是，尽管如此走向21世纪的液压技术不可能有重大的突破，应当主要依靠现有技术的改进和扩展不断扩大其应用领域以满足未来的要求。其主要发展趋势将集中在1） 减少能耗，充分利用能量2） 泄露控制3） 污染控制4） 主动维护5） 机电一体化6） 液压CAD技术7） 新技术、新工艺的应用随着液压技术的发展，作为完成刀架切削运动和进给运动的部件液压动力滑台自然也得到了长足的发展。它使得零件的加工质量得到了较大的提高。而本课题正是为了设计出能够给组合机床提供平稳、可靠的进给运动动力部件液压动力滑台而展开的。液压动力滑台有关备用数据的计算1对镗削头重力的估算（图见组合机床设计附表6）： 2对滑台重力的估算（图见组合机床设计简明手册表5-3） 3镗削头和滑台总重第1章 液压缸的结构设计1.1 负载图及速度图1.1.1 负载分析切削力摩擦阻力Ffs =fsG =0.23060.72=612.14NFfd =fdG =0.13060.72=306.07N惯性阻力Fm =ma =31210/0.51/60=104N重力阻力因工作部件卧室布置，固重力阻力为零。密封阻力将密封阻力考虑在液压缸的机械效率中去，取液压缸的效率m=0.9背压阻力背压力PB由后面选取根据上述分析（没有考虑颠覆力矩的作用）可算出液压缸在各动作阶段中的负载，如表1所示。表1 液压缸各动作阶段中的负载工 况计算公式液压缸负载F/N液压缸推力F/M=F/0.9N启 动F=Ffs705.50783.89加 速F=Ffd+Fm472.61525.12快 速F=Ffd 352.75391.94工 进F=Fl+Ffd10352.7511503.06快 退F=Ffd352.75391.941.1.2 负载图、速度图快进速度1与快退速度3相等，即，行程分别为，；由查表得：工进速度，即，行程。根据这些数据和表1中的数值绘制液压缸的负载图和速度图，如图1、2所示。1.2 初定液压缸的结构尺寸1.2.1 初选液压缸的工作压力p1p1 =30105Pa1.2.2 计算液压缸的结构尺寸因，故选用单活塞杆式液压缸，使A1 =2A2，且快进时液压缸差动连接。因为是镗孔加工，为防止镗通孔时工作部件突然前冲，回路中应有背压。暂取背压为a快进时，液压缸差动连接。由于管路中有压力损失，所以这时液压缸有杆腔的压力p2必大于无杆腔中的压力p1。若估取这部分损失为p=5105，则p2 =p1+p =p1+5105Pa。快退时，油液从液压缸无杆腔流出，是有阻力的，故也有背压。此时背压亦按5105Pa估取。以下求液压缸的工作面积按标准取D =74mm。液压缸活塞杆直径d为:d =0.707D =0.70774 =52.3mm按标准取d =52mm。由此求得液压缸有效工作面积为无杆腔面积 A1 =d2/4 =742/4 =42.99cm2有杆腔面积A2 =(D2-d2) =(742-522) =21.76cm2查得调速阀Q-10BQ-100B最小稳定流量QVMIN =0.05L/min =50cm3/min。由公式A（A1或A2）Qvmin/min验算液压缸的有效工作面积，即A1 =42.99cm2 Qvmin/min =50/0.035102 =14.29cm2A2 =21.76cm2 Qvmin/min =14.29cm2所以，流量控制阀无论是放在进油路上，还是放在回油路上，有效工作面积A1、A2都能满足工作部件的最低速度要求。1.3 液压缸工况图液压缸工作循环中各动作阶段的压力、流量和功率的实际使用值，如表2所示。表2 液压缸工作循环中的压力、流量和功率 液压缸工况 负载 回油压力 输入流量 进油腔压力输入功率 计算公式 F/N P2/(105Pa) Q/(L/min) p1/(105Pa) P/kw快 启动 783.89 / / 3.69 / 加速 525.12 p2 =p1+p / 7.60 / Q=(A1-A2)进 恒速 391.94 =p1+5 21.23 6.97 0.247 P=p1Q 工进 11503.06 6 0.150 29.79 0.007 Q=A12 5.80 0.288 P =p1Q快 启动 783.89 / / 3.60 / 加速 525.12 5 / 12.29 Q =A23退 恒速 391.94 5 21.76 11.68 0.424 P =p1Q：启动时活塞尚未动作，故取：p =0(快进时);p2 =0（快退时）。：因加速时间很短，故流量不计。根据上表可绘制出液压缸的工况图，如图3。 上表中的具体计算过程：1.快进启动时Pa加速时 =7.60105Pa恒速时Q =6.97105PaP =p1Q =6.9710521.2310-3/60 =0.247kw2.工进Q =A12 =42.9910-4(0.0351.35)=0.1505.80L/minp1= =29.79105PaP =p1Q =29.79105(0.1505.80)10-3/60 =0.0070.288kw3.快退启动时Pa加速时=12.29105Pa恒速时=11.68105Pa P =p1Q =11.6810521.7610-3/60 =0.424kw第2章 拟订液压回路2.1 选择液压回路2.1.1 调速回路及油源型式由工况图知，该机床液压系统功率小（1KW），速度较低；钻镗加工为连续切削，切削力变化小，故采用节流调速回路（开式回路）。为增加运动的平稳性，防止工件钻通时工作部件突然前冲，采用调速阀的出口节流调速回路。由工况图还可看出，该系统由低压大流量和高压小流量两个阶段组成，其最大流量与最小流量之比为Qmax/QMIN=21.76/(0.1505.80)=145.073.75。若按平均值考虑（即较多工况出现2=0.0351.35m/min的平均值上），则上述比值仍很大。故为了节约能源，采用双定量泵供油。如图(a)所示。2.1.2 调速回路及速度换接回路因系统快进快退速度相等，故快进时采用液压缸差动连接的方式，以保快进快退时的速度基本相等。由于快进、工进之间的速度差较大，为减少速度换接时的液压冲击，采用行程阀控制的换接回路。如图（b）所示2.1.3 换向回路由工况图可看出，回路中流量较小（在快退时，进油路上的流量为21.76L/min，回油路上为21.7642.99/21.76=42.99），系统的工作压力不高，故采用电磁换向阀的换向回路，如图(b)、(c)所示。2.1.4 压力控制回路在双定量泵供油的油源型式确定后，卸荷和调压问题都已基本解决，即工进时，低压泵卸荷，高压泵工作并由溢流阀调定其出口压力。当换向阀处于中位时，高压泵虽卸荷，但功率损失并不大。故不再采用卸荷回路，以使结构简单些。2.1.5 行程终点的控制方式这台机床用于钻孔（通孔与不通孔）和镗孔加工，因此要求位置定位精度较高。另外，对于镗孔加工，为保证“清根”（使刀具在工进结束、但尚未退回之前，有个短暂停留原地回转），在行程终点采用死挡铁停留的控制方式（即滑台碰上死挡铁后，系统压力升高，由压力继电器发出信号，操纵电磁铁动作，电磁换向阀切换）。2.2 组成液压系统图由图(a)、(b)、(c)所示的液压回路图组成液压系统图，如图4所示。和图（a）、(b)、(c)相比，系统图中增添了单向阀10、二位二通电磁阀11。这是因为若没有阀10和11，液压缸便不能自动退回原位，即在快退过程中，当液压缸移至快进与工进的换接处时，行程阀8将恢复常位（左位），这时液压泵的来油将被背压阀8的左位截止（当无阀10时）或经阀10、阀8左位、阀5 右位直接流回油箱（当有阀10但在通道a、b上无阀11时）。图4所示油路系统在电器及固定在滑台上的行程挡铁配合下,完成了所需要的工作循环：滑台快进工进死铁停留快退原位停止具体的工作循环如下： 滑台快进:按下“向前”按钮,电磁铁1DT、3DT通电,使阀5左位、阀11上位、阀8左位接入系统进油油路:泵1导管13阀5左位导管14、15油缸后腔回油油路:油缸前腔导管16阀8左位导管18阀11上位导管15油缸后腔,实现差动连接,完成滑台的快进运动. 工进:滑台快进到达预定位置,由安装在滑台侧面的一次行程挡铁压下 行程阀11,3DT断电,阀8右位接入系统.进油油路:泵1导管13阀5左位导管14、15油缸后腔回油油路:油缸前腔导管16阀8右位导管17调速阀6阀5左位油箱 滑台停留:滑台工进终了,滑台体前端顶上固定在滑座体上的死挡铁,滑台不能前进,而油路系统仍在供油,迫使油缸后腔油压升高,压力继电器9发出信号,使电磁铁2DT通电、1DT断电,实现滑台快退.压力继电器9延时的过程就是滑台在死挡铁停留的时间. 滑台快退:由于2DT通电,使阀5右位接入系统进油油路:泵1导管13阀5右位导管18单向阀7导管19、17、20单向阀10导管21、16油缸前腔回油油路:油缸后腔导管15、14阀5右位油箱 滑台原位停止:滑台回到原位时,行程挡铁压下原位开关,发出信号,切断全部电磁铁电源.阀处于中间位置.泵的流量接近于零,滑台原位静止.图5为液压系统的控制电路图。滑台在原位时，行程开关1XK被挡铁压动，其动合触点闭合，动断触点断开；当将旋钮开关1K放在“2”位置时，按动旋钮1QA，滑台可点动向前调整；若滑台不在原位，按动1DA，滑台可点动后退，直至原位。表3为电磁铁动作顺序表。图6为液压系统的动作循环。表3 电磁铁动作顺序表元件动作1DT2DT3DT1QA3XKYJ1XK快进+-+-工进+-快退-+-停止-+图4 液压系统图第3章 计算和选择液压元件3.1 确定液压泵的规格和电机功率3.1.1 液压泵工作压力的计算确定小流量泵的工作压力小流量泵在快进、快退和工进时都向系统供油。由工况图可知，最大压力为Pa。在出口节流调速中，因进油路比较简单，故进油路压力损失取Pa，则小流量泵的最高工作压力为Pa确定大流量泵的工作压力大流量泵只在快进、快退中供油。由工况图可知，最大工作压力为Pa。若取此时进油路上的压力损失为Pa。则大泵的最高工作压力为Pa3.1.2 液压泵流量的计算由工况图可知，液压缸需要的最大流量为21.76L/min，若取泄露折算系数K =1.1，则两个泵的总流量为.因工进时的最大流量为5.80L/min（见工况图），考虑到溢流阀的最小稳定流量(3L/min)，故小泵的流量最少应为8.80L/min。3.1.3 液压泵规格的确定按1+（2560）%=34.791+（2560）%=（43.4955.66）105，Qp =23.94L/min.查产品样本或设计手册，选取YB-10/14型双联叶片泵，额定压力为63105Pa.3.1.4 电机功率的确定由工况图上可知，液压缸最大功率出现在压力为PMAX=0.424kw、流量为21.76L/min的快退阶段，这时泵站输出压力为11.68105Pa+5105Pa=16.68105Pa，流量为24L/min。若取双泵总效率为p=0.75，则所需电机功率为kw按产品目录（或设计手册）须选用功率为1.1kw、同步转速为1000r/min的电动机。3.2 液压阀的选择根据系统的最高工作压力（泵的工作压力）和通过各阀的最大实际流量，选出的各阀的规格如表4所示 序号液压泵名称通过的最大实际流 量/(L/min)型号规格接口尺寸数量1双联叶片泵YB-10/14(10/14)L/min6.3Mpa12溢流阀10Y-25B25L/min6.3MPa1213顺序阀14XY-25B25L/min6.3MPa1214单向阀14I-25B25L/min6.3MPa1215三位四通电磁换向阀4434D-63B63L/min6.3MPa1816调速阀3.4Q-25B25L/min6.3MPa1217、10单向阀24I-25B25L/min6.3MPa1228二位三通机动换向阀2423C-25B25L/min6.3MPa1219压力继电器/DP1-63B调压范围16.3MP11111二位二通电磁阀2422D-25B25L/min6.3MPa12112滤油器24XU-4010025L/min6.3MPa113压力表开关/K-6B6.3MPa413.3 确定管道尺3.3.1 压油管道由公式得=0.01010.01428m =10.114.28mm按以选定的标准元件接口尺寸取d =12mm。3.3.2 吸油管道=0.01840.0319m =18.431.9mm取d =25mm。3.3.3 回油管道=0.02020.0261m =20.226.1mm取d =25mm。三种管道皆为无缝钢管。3.4 确定油箱容量按推荐公式V =(57)Qp,取V =624=144L。第4章 液压系统主要性能的估算下面主要对液压缸的速度（流量）、系统效率和温升（发热）进行估算。4.1 液压缸的速度在液压系统各个组成元件确定后，液压缸在实际快进、工进和快退时的输入、排出流 量和移动速度，已与题目原来所要求的数值不尽相同，故需重新估算。估算结果列入表5中。 流量及速度工序输入流量（L/min)排出流量(L/min)移动速度(m/min)快进（差动）工进Q1 =0.1505.80=0.0762.942 =0.0351.35快退Q1 =QP =244.2 系统的效率4.2.1 回路中的压力损失计算回路中的压力损失时，必须知道管道的长度和直径。管道直径按选定元件的接口尺寸确定，即d =12mm，回路中进、回油管长度（因液压装置尚未设计出来）暂且都按 =2m估算。油液的运动黏度取m2/s。系统中有关元件的额定压力损失见表6。表6 液压件在额定压力下的额定压力损失 元件压力损失34D-63B22D-25B23C-25BI-25BQ-25BXY-25Bpvn/(105Pa)421.5253快进时的回路压力损失快进时进油管中的流态为层流，即448.6010-3/1210-37510-660=194.4/16956010-6=11462320，故进油管的沿程损失为 Pa进油管的局部损失估取为Pa进油路上，油液只经过一个三位四通电磁换向阀5，参照表6，该阀上的局部损失为 =2.38105Pa由此得快进时进油路上的压力损失为Pa同样可以判断出回油管中亦是层流，并计算得压力损失分别为 PaPa此时，回油经过二位二通电磁阀11和二位三通行程阀8，回油量Q2 =24.60L/min。阀11、8的局部压力损失为 Pa由此可得快进时回油路上的压力损失为Pa将回油路上的压力损失折算到进油路上去，便得出差动快进时进油路（即整个回路）上的压力损失=7.98105Pa这个数值的精确值是顺序阀3调整压力的下限参考之一（尚须和快退时的压力损失相比较，即在快退运动时，阀3必须保证不被打开）。工进时的回路压力损失由45.8010-3/1210-37510-660=23.2/16956010-6=136.822320，可以得出工进时进油管中的流态为层流，故工进时进油管的最大沿程损失为 Pa进油管的最大局部损失估取为Pa进油路上，油液只经过一个三位四通电磁换向阀5，参照表6，该阀上的局部损失为 =0.034105Pa由此得工进时进油路上的压力损失为Pa同样可以判断出回油管中亦是层流，并计算得压力损失分别为 Pa回油管的最大局部损失为Pa此时，回油经过二位二通电磁阀11和调速阀6及三位四通电磁阀5 Pa得工进时回油路上的最大压力损失为Pa所以，整个回路的压力损失为Pa快退时的回路压力损失由42410-3/1210-37510-660=96/16956010-6=66.17 12.88105Pa4.2.4 液压回路和液压系统的效率工进时，液压缸的工作压力为=26.91105Pa经阀3使大流量泵卸荷时的压力损失为(14/25)2=0.94105Pa，则回路效率为c = =(4.0365156.078)105/(287.66105)=0.0140.543泵的效率取，液压缸的效率取（即设液压缸的容积效率为1），则系统的效率为由此可见，定量泵系统在低速时效率是很低的。4.3 液压系统发热与温升的验算在本题中，快进、工进和快退所占用的时间（秒）分别为快进s工进5.56214.29s快退s在整个工作循环中，快进占0.31%8.7%，快退占0.63%17.94%，工进占73.35%99.07%，故温升应按工进工况验算。工进时，液压缸输出的有用功率为=10352.75(0.0351.35)/60 =0.006040.233kw泵的输入功率为 kw故得系统发热量为=0.639-(0.006040.233)=0.6320.406kw系统温升（设通风良好） =14.7823.01查设计手册中机床的允许油温正常工作油温最高允许油温油及油箱的温升机床305055703035由此可知，本系统温升小于规定的允许温升值。第5章 导轨的设计计算与检验5.1 导轨的设计计算5.1.1 导轨的跨距 据实践经验：镗床 本设计中选取 由设计要求知 B=250mm5.1.2 导轨的跨度根据滑台的行程和国标，取导轨长度L=790mm.5.1.3 导轨面的尺寸 通常 这里取 根据标准列表取则有 此导轨采用矩形导轨和山形导轨相结合的形式。山形导轨的简图如图7。取，设c为导轨内侧宽度，d为山形导轨外侧宽度，b为矩形导轨宽度。通常c=(1.21.4)d b=(0.81)d承上 b=40mm则按标准数列表中选取 c=48mm d=40mm由计算得知 由此，山形导轨的当量宽度。 而 5.2 导轨的许用比压值的计算导轨的许用比压值 由前面液压系统设计中可知，镗削头和滑台总重G=5125.35N接触面积5.3 导轨面比压的计算本设计液压滑台与TA25型机械镗削动力头配合。该镗削头主轴转速为500r/min,电机功率取2kw，主轴中心高125mm，镗孔直径为32125mm，且知主切削力FZ偏离滑台中心（以下相关数据参见组合机床设计附表6）主轴转速主切削力若刀具时之间有如下近似关系若取若不计滑台及镗削头的重力，导轨受力如图8（相关公式、数据参见金属切削机床） 前导轨承受后导轨承受 如果将移至线y-y上，则将产生转矩及与等大的,如图9所示。 其实，导轨还需承受液压滑台和镗削头的重力，所以，必须考虑它们对导轨的影响。已知G=5121.35N，若不考虑切削力，设重力作用于滑台中心，导轨受力如下图。 此时，综合考虑切削力和重力前导轨承受N后导轨承受而对于切削导轨则有因此，各导轨面的平均比压为（滑台与导轨接触长度500mm）故导轨面的平均比压都符合要求。由于要讨论导轨与滑台的接触情况，需将液压滑台与镗削头总重力与切削力合成一个外力来看它偏离滑台中心的情况。则 得F=5732.8N，y=6.66mm,x=39.44mm 导轨比压分布图形为梯形，符合要求，即保证全长接触。通过此次毕业设计，我切身体会到了作为未来工程师的艰辛。为了能够顺利、圆满地完成此次设计任务，我每天都在忙碌着。说实话，还真是挺辛苦的。但是，总的说来，我认为这种生活还是很充实，很有意义的。特别是看着自己的劳动成果，一股自豪感和成就感从心底油然而生，一切的劳累也就烟消云散了。在此次毕业设计中，我对液压动力滑台的结构和其液压系统作用原理有了清晰而又深刻的了解。同时，我又把曾经学习过的Auto CAD的绘图技术和电子图板的绘图技术都完整地复习了一遍，并且还完善了许多。对于以前尚未掌握的绘图指令和绘图技巧有了更加深刻的理解和领悟。尤其是在编写说明书的过程中，我对Microsoft Word 软件各种功能能够很熟练地掌握。总之，此次毕业设计确实使我受益匪浅。同时，它也使我增加了自信，从而使我有足够的信心去迎接明天的挑战。当然，由于我的知识有限、经验不足，尽管已经努力了，但是在设计中还是难免会出现一些不足和疏漏。我真诚希望各位老师和同学多多指正。结束语通过本课题的设计，我了解到近代液压技术的形成和发展迄今已大体上经历了：走向标准化、走向优质化和走向智能化三个阶段。现在它还处在第三阶段的中途。液压技术的主要优点突出在它适应了近代科学技术发展的总趋势：力图提高工作机械的效率，减小其体积和重量，加大其输出功率。在标准化阶段，它使得各种液压系统和元件之间拥有共同的构思和公用的术语，实现了它们之间的共通和交流，从而促进了液压技术的蓬勃发展。在优质化阶段，它使得液压技术在前进中暴露的缺点明显的改进。例如，在增加元件寿命、降噪、防漏、治污和节省能量等方面都得到了长足的发展。尤其在防漏、治污、节省能量方面尤其如此。在防漏方面，通过密封材质的正确选择、接口技术的更新，许多液压装置已基本上做到不再漏油；在治污方面，通过正确选用过滤材质和滤心结构、正确安排滤油器位置，已可使液压系统中的油液达到医疗级的纯净程度，使液压件的可靠工作寿命提高数倍到数十倍；在节省能量方面，以水代油、功率回收等实践性探索工作都取得了很大的发展。并且与此同时，液压件的结构不断地向小型化、集成化的方向发展，体积越来越小，结构越来越紧凑，中间通道越来越短。但是，随着客观现实对液压装置要求的不断提高，许多开关系统，不管设计得如何完善、周到，都无法实现这些要求，不得不让位于伺服系统和比例系统。于是液电结合就成为液压技术发展中的一种趋向。向智能化方向发展这正是液电结合趋向前进的必然结果。这种结果是液压技术彻底改变了自身的传统面貌，是它变成了一个包括传动、控制、检测等在内的完整的自动化技术，成为几门学科的交叉结合点。虽然液压技术的智能化才刚刚开始，但是从它星星点点实践成功的事例来看，成果已非常诱人。总之，液压技术在与微电子紧密结合后，在微计算机或微处理机的控制下，可以进一步拓宽它的应用领域，形形式式机器人和智能元件的使用不过是它最常见的例子而已。现在国外已在着手开发多种行业能通用的智能组合硬件，它们只须配上适当的软件就可以在不同的行业中完成不同的任务。综上所述可以看到，液压工业在国民经济中的作用实在是很大的，它常常可以用来作为衡量一个国家工业水平的重要标志之一。与世界上主要的工业国家相比，我国的液压工业还是相当落后的，标准化的工作有待于继续做好，优质化的工作还未形成声势，智能化的工作则刚刚在准备起步，为此必须急起直追，才能迎头赶上。谢词由于我是第一次做如此大型的设计，在加上我经验不足、知识有限，所以我不时地会遇到很多困难。但是每当我遇到困难的时候，我总是会得到很多老师和同学的帮助，尤其是我的指导老师王凯老师、班主任汪生梅老师及丁叙生老师的孜孜不倦的指导给了我很大的启发和帮助。也正因为如此，我才得以顺利地完成此次任务。在此，我向王老师、汪老师、丁老师及所有帮助过我的老师和同学们表示衷心地感谢由于我知识有限、经验不足及时间仓促，本次设计不免会出现一些不当和疏漏之处，真诚希望各位老师和同学们多多指正。参考文献沈阳工业大学主编.组合机床设计.上海科技出版社,1985.9,第一版金振华.组合机床及其调整与使用.机械工业出版社,1990,第一版东南大学章宏甲.液压与气压传动.机械工业出版社,2000.5,第一版贾铭新.液压传动与控制.国防工业出版社,2000.1,第二版姚永明.非标准设备设计手册.上海交通大学出版社,1999.12,第一版手册组.机床设计手册.机械工业出版社,1986.12,第一版 金属切削机床(组合机床设计及机床自动控制).南京航空学院, 1975.5 Richard P.Paul Manipulators: Machematics Programming and control, MIT Press, 1981. 附录：(译文资料)EXPERIMENTAL DEVICES OF PRODUCING SCRAPRUBBER POWDER WITH WAVE CRYOGENIC TECHNOLOGYGao Guangfan Fang Yaoqi Jin LianganSchool of Chemical Engineering,Dalian University of Technology, Dalian 116012,China Abstract: A system of producing scrap rubber powder with wave cryogenic technology is put forward. Main equipments such as wave refrigerator, vortex pulverizer and fluidized cooler are presented. The key techniques about silica gel refreshing in desiccators and system drying are discussed. The potential improvement of the system is pointed out. The manufacturing cost is lower than the cost of liquid nitrogen cryogenic method, and the quality is better than that of normal temperature milling. Moreover, wave refrigerators have several advantages over turbine expanders applied in the cryogenic milling system. Key words: Rubber powder Pulverization Wave refrigerator Experimental devices 0 INTRODUCTIONRubber powder(RP) is the crushed from of scrap rubber, which can be used as industrial producers goods directly and needs no regenerating. The less the grain size of RP, the better the performance of RP productions. The season is that its specific surface area will get bigger and mixing effect will be better with the decreasing of grain size.Normal temperature milling and cryogenic milling are two methods for the manufacturing of RP. The former method can be further classified into dry, damp and chemical crushing. The grain size of RP is usually from 20 to 30 meshes. In the normal temperature milling, crushing of rubber grain(RG) is carried out by shear force. As time of heating course is quite long, it is easy to get aging, and the quality decayed. Very low output is another shortcoming of normal temperature milling, the manufacturing capacity in China is only 4050 kg/h. There are two methods, mechanical crushing and vortex pulverization, in cryogenic milling. The grain size of RP is ordinarily from 60 to 200 meshes. After the temperature of scrap rubber is lower than the vitrified point, the milling is carried through by wallop. The manufacturing capacity is quite high; grain size is small, steel wire and fiber almost separated entirely. Liquid nitrogen and air refrigeration are the comer means to achieve low temperature. The former method is feasible in developed country on the condition that the scrap rubber is free of charge and liquid nitrogen is cheap. The wastage of liquid nitrogen is about 1.01.5 kg/kg RP and the price of one kilogram liquid nitrogen is about 0.4 dollar in China, it is obvious that RP producing with liquid nitrogen is not cost-efficient in China. Rp manufacturing with air refrigeration causes no second pollution, which provides a new approach to recycle scrap rubber in our country. Up to now, air refrigeration achieved mainly by turbine expander, this paper recommends an experimental system of producing RP with wave cryogenic technology.1 TECHNICAL PROCESS PLANNING The process chart of experimental system to make RP from scrap rubber is illustrated in Fig.1, a wave refrigerator(WR) supplies the needed freezing cold air and the crushing facility is a vortex pulverizer. The freezing and crushing of RG is in intermittent operation. Air compressed by reciprocating compressor 1 passes through oil & water separator 2(which is cooled by water) then comes into oil strainer 3, in which residual oil molecule in the air is removed. Cushioned and stabilized in container 4, the air flows into air desiccators 5, in which its residual moisture is removed by silica gel. Before entering into WR 7, the pressured air is pre-cooled in a plate-fin heat exchanger 6. Its temperature is dropped largely by the WR through the mechanism of shock tubes. Afterward, the flow direction of cold air varies with the different operational stages. During the freezing of RG, cold dry airflow passes through fluidized cooler 8, fore cooler 10, rotary blower 13 and plate-fin exchanger then returns to the air compressor and continues its cycle.The stage of pulverization begins after the temperature of RG in the fluidized cooler falls to a certain value low than the vitrified point. Discharged from the WR, cold air that has certain pressure ejects tangentially into crushing cavity of vortex pulverizer 9. At the same time, under the forcing of pressure difference, RG flows into the cavity of vortex pulverizer continuously and is crushed. After the cold airflow flows out the vortex pulverizer, it passes through both upper and lower cyclone separator 11 and 12, then pressured by the Fig.1 Process chart of scraf rubber pulverizationWith wave cryogenic technology1. Air compressor 2. Oil & water separator 3. Oil strainer4. Air container 5. Air desiccators 6. Plate-fin exchanger7. Wave refrigerator 8. Fluidized cooler 9.Vortex pulverizer10. Fore cooler 11. Upper cyclone 12. Lower cyclone13. rotary blower 14. Rubber powder classification15. Product collection 16. Rubber grainrotary blower. At last, it returns to the air compressor via plate-fin exchanger and continues its cycle. Before gets into fluidized cooler, dried RG in fore cooler calls back parts of cold energy from cryogenic airflow. RP crushed in vortex pulverizer enters into upper and lower cyclone separators from two exits of vortex pulverizer respectively and cumulates in there. Finally, classification and collection of RP is performed. The technical process of this system is a closed-cycle. Air is compressed and frozen continually in the system; the supplementary air needed in the cycle is very small, which lessens the burden of purified equipment. Furthermore the losing of cold is quite small. The initial cooling of airflow by efficient plate-fin exchanger and pre-refrigeration of RG in fore cooler cuts down the irreversible loss of cold, they are propitious to reduce production cost of RP.2 MAIN EQUIPMENT2.1 Wave refrigeratorThe WR is the core machine. It is composed of a rotating nozzle tray(usually has two outlets with converging flow passage), a large number of shock tubes mounted radially around the periphery of the nozzle tray, and other components such as shock attenuators, seal gland, hollow rotating axis and rolling contact bearings. The flow passage of nozzle is not radial, so the tray rotates automatically by the driving of tangential force. Besides, an electric motor can be installed at the end of the axis if rotating speed needs to be compulsorily controlled.The nozzle tray is rotated to pass through many stationary shock tubes. While the rotating nozzle aligns with any shock tube at time interval, which is exposed to drive air, a moving shock wave is formed in the tube. The gas originally in the tube is heated by the propagating shock wave; the heat transfer dissipates the heat energy across the tube wall. With the rotation of nozzle tray, the tube connects to the lower pressure exhaust pipe. When the cold driver gas is discharged completely, a new cycle begins. The temperature of discharged cold air may be 120, which exactly meets the need of cryogenic crushing of scrap rubber. The WR has less moving parts and wearing parts, simple structure, and wide operating scope. There is less difference of isentropic efficiency between WR and turbine expander. But its rotating speed is much less than turbine expanders(they are about 1 kr/min and 1090 kr/min respectively). Its flow rate may be from 1103 to 5.5105 m3/d and inlet gas pressure may be from 0.45 to 10 Mpa. It has been successfully employed to separate oil well gases, to trap water from natural gases etc. Consider for its flow rate and outlet temperature, the WR is expected competent for large scale industrial production of RP.2.2 Fluidized coolerThe fluidized cooler is a cylindrical vessel with two heads. A cone hopper perforated with many triangular holes is mounted on the lower head. A plug-board valve and a feed pipe connected with vortex pulverizer are rightly down the hopper. An annulus air inlet pipe with many holes is mounted in the space between hopper and lower head. The upper part of the vessel connected with fore cooler through an inclined feed pipe is on the top of vessel.On the stage of freezing of RG, cold air ejects into the room with certain speed from the little holes of hopper. RG is at fluidized state. Forced heat transfer by convection and large area of heat transfer shortens the time of freezing. On the stage of pulverization, cold air discharged from WR turns into vortex pulverizer. With the plug-board valve opened. RG flows to the pulverizer by the driving of pressure difference. The opening ratio of the valve is determined by the grain size. 2.3 Vortex pulverizerThe cold airflow with certain pressure discharged from WR provides the needed driving power for vortex pulverizer. There are no rotating parts in the pulverizer. Its core part is a short cylindrical cavity with many blades mounted on the wall. The inlet spout is tangential and narrow, which is also oh the wall. The shape of spout may be converging or converging-diverging, which is determined by operating conditions. The feed pipe is perpendicular to the bottom plane of crushing cavity, and the height of clearance can be changed with different grain size. There are two locates of vents, an annulus outside of the feed pipe and several narrow tangential slots on wall. Cold airflow ejects tangentially into the cavity with high speed from the inlet spout and forms very strong vortex flow field. Sub-atmospheric pressure occurred in the center of swirl, RG is sucked continuously into the cavity. The variation of velocity field makes the fragile RG collide each other. Moreover, RG on the outside of swirl collides sorely with the blades. The outside flow moves down while the inside moves up, then the crushed RP flows automatically out the cavity along with the cold airflow.3 TECHNICAL EXPLATION3.1 Refreshing of silica gelWhen moisture content in silica gel is about 40%, its ability is almost lost. So the refreshing of silica gel in desiccators is needed. The temperature in experimental system especially in crushing area is quite low. It is necessary to control the moisture in airflow strictly. Two parallel-connected air desiccators are equipped(Fig.2)which can reduce the diameters and distribute the airflow uniformly. In terms of conditions such as moisture content in air and milling capacity, only one or both desiccators may be used in the operation. Much more important is that silica gel may be rapidly refreshed by means of mutual assistance(see Table). For example, if we want to refresh silica gel in desiccator 2, open the cut-off valves 1, 4, 5, 6 and valves 2, 3, 7 and 8 are closed. The moisture in compressed air is pre-trapped by desiccator 1, then the air is heated by a electric heater(4KW), the heat wet air flows through disiccator II and vents out from valve 4. The temperature at exit of the electric heater is controlled at 175+5, the temperature on the top of desiccator is 110+5(maintained about two hours). It must be pointed out that the temperature of silica gel should not be over 30 before starting operation.Fig.2 Layout of air desiccators1. Desiccator I 2. Electric heater 3. Desiccator IITable State of valve at different conditionsCondition12345678RefreshingOCCOOOCCRefreshingCOOCOOCCUsingOCCCCCOOUsingCOCCCCOOUsing&OOCCCCOOOOpen CClose3.2 Maintenance of the systemThe crushing equipment runs under cryogenic condition, which makes the maintenance of system much mor difficult. Following items should be paid more attention. 1. When ready to start the operation, make sure that there is no any residual water or ice in the system. Blowing vent should be the lowest position of system. 2. The system after the air container must be well preserved by heat insulating layer. 3. In order to avoid super fine RP entering to cylinders of compressor, wire meshes ought to be mounted at several key positions. Wire meshes must be designed carefully to avoid large resistance. 4. To cut down the large amount of oil molecule in air, make sure that air compressor is in good condition and oil level in crankcase is too high. 5. All joints should be well sealed. Whether is in operating or not, the system ought to be closed.4 CONCLUSIONMany tests have been done for the tread rubber. The grain size is from 2.5 mm to 6 mm and the ratio of length to width is no more than 1.5. The temperature of drying RG is maintained at 110+2 for 3 h and the freezing temperature of RG in the fluidized cooler is kept at 95+3. Exhaust pressure of air compressor is 0.8 Mpa(gage) and the air displacement is 10m/min. The pulverization capacity is 150 kg/h and the air pressure before vortex pulverizer is 0.2 Mpa(gage). According to the grain size groups of lower than 30 meshes, 3080 meshes and equal to or greater than 80 meshes, the mass of RP obtained accounts for 18%, 34% and 48% respectively. The electric power consumption of RG is about 500 kmh/t. Not counting expenses of storage and transportation of liquid nitrogen, the manufacturing cost of RP by the method of wave cryogenic technology is about from one fourth to one third of that by the method of liquid nitrogen refrigerating. Some techniques need to be further studied or improved. Following are several of them; With added equipment, the cold may be utilized more reasonably in industrial pulverization system. The difference between the vitrified points of different rubber is quite large. Even though not accounting to the unusual ones, the vitrified point varies from 75 to 50. Considering that a tire has several kinds of rubber, ascertain of the vitrified point of tires is much helpful to control the pulverization temperature accurately. The optimized matching of characteristic parameters of the vortex pulverizer and operational conditions needs further in-depth researches. References1 Fang Yaoqi, Zheng Jie, Liu Runjie, et al. Experimental study of gas wave refrigeration. In:Proc. 18th Int. Symp. On Shock Wave, Sendai,1991:133513382 Yu Hongru, Fang Yaoqi. The thermal separator and its application to the generation of cryogenic flow. In:Proc.6th Asian Cong. Of Fluid Mechanics, Singapore, 1995:62663 Liang Shibin, Fang Yanqi, Zhu Che. Experiment study for paricle size reducyion of materials using cryogenic technology. Of Refrigeration, 1995, 65(3): 2729Biographical notes:Gao Guangfan, male, born in 1964, doctoral student. Major in chemical process machinery.Tel:+86-411-3687814;E-mail:g_gf INTEGRATION OF STORAGE CHARACTERISTICWITH ON-LINE SERVICE CHARACTERISTIC OF AS/RSWu Yaohua Zhang Qiang Zhang DanyuCenter of Material Handling Engineering,Shandong UniversityAbstract：Directed at how to integrated storage characteristic with on-line service characteristic of AS/RS, a solution based on database design and programming method is proposed. The results show that this model is reasonable and applicable while using in some small or middle enterprises material handling system. Key words: MHS AS/RS Inventory management database0 INTRDUCTIONAS/RS is a basic element of the modern material handling system. It has two main advantages: First, it can save storage spaces and enhance its storage capacity by its elevated structure; Second, it features of automated storing and retrieving and ensures high out warehouse efficiency due to being controlled by computers and PLCs, interfacing with production or sell processes, on-line feeding service can be provided. AS/RS emphasizing on the first advantage can be called storage-oriented AS/RS, while AS/RS emphasizing on the second advantage can be called on-line service-oriented AS/RS. Because automated handling and storage system is very expensive, multiple AS/RSs with different purposes cannot be afforded by many middle or small scale enterprises, but there exist internal conflicts and difficulties in integrating two advantages into one AS/RS. A solution based on database design and programming method is proposed during our developing process in Great-River Motor-Car Factorys material handling system, the AS/RS with is management method take both advantages and can be easily operated. 1 CONFLICTS BETWEEN TWO ADVANTAGESIt is out-ware house efficiency that on-line service-ori-ented AS/RS guarantees with. So zoning storage should be adopted, placing material with high out-warehouse frequency in fields near to the egress and the whole unit should be directly sent to the production line without picking operation. Because the parts of motor-cars engine are big enough, several kinds of parts must be placed in one unit tray, so fixed assembly scheme must be formulated in advance and the priorities abided by during which are as such: The parts belong to one kind of engine should be prior combined. The parts needed by adjacent buffers should be prior combined. The parts with the same out-warehouse frequency should be prior combined. Package size should be fitted to each other to save space. Storage-oriented AS/RS aim at high warehouse utilizing rate. Without a central warehouse to store materials temporarily, most parts should input to AS/RS immediately after parts are delivered to factory, small parts of materials can be waited for fixed assembly at input side of AS/RS. The assembly priorities most parts should take will be as such: First arrive, first in. Any kinds and any number of parts can be assembled in one tray. package size should be fitted to each other to save space. According to above analyses, two functions of AS/RS differ from each other at the aspects of storage unit allocation rule and tray assembly priority. Solving this problem should begin with database design.3 DATABASE DESIGN INNOVATIONThe key problem to solve this conflict is to achieve one warehouse, two management mode, fixed tray assembly and random tray assembly. First, to ensureits on-line service function. AS/RS zoning rule and tray assembly priority should first take warehouse efficiency into consideration, then a special tray code- random assembly tray code is added, AS/RS is informed once a tray with this code is scanned at the input end, then a different management mode is used to fit with these trays. The main database table structures are shown in Fig.1.Tray code Tray batch code Fixed-assembly tray informationPart arrive batch No.Tray batch code Batch number Part number In-status Tray batch code Random-assembly tray informationAssembly time Part number Part arrive batch No. Assembly Assembly time Random-assemblytray in tableIn-status Tray batch codePart arrive batch No. Tray code Part code Tray batch codeArrive number number Field No. Part arrivebatch tableWarehouseunit tableaaawRow number FactoryLayer number Arrive date Bay number Check status In-out time (a) (b)Fig.1 Innovated database design to combine two functions of AS/RSIn Fig.1, there are there main codes which run through the whole management process: The first is the parts arriving batch No. which identifies a batch of parts arriving status which include arriving number information, manufacturing factory information and check status information, ect; The second is the tray code, which is the unique identifier to distinguish AS/RS unit from each other which could be fixed tray code or random assembly tray code; The third is the tray batch code which generated during tray assembly process and link the material in the AS/RS unit with part arriving batch No. The logic process of AS/RS inventory information tracing in shown in Fig.2. Read tray code in AS/RS unit Random assemblyFixed tray code tray code JudgementRead from random-assembly tray information tableRead from fixed-assembly tray information tablet Get part arrive batch No. Get part detail information from part arrive batch tableFig.2 Logic process of AS/RS inventoryinformation tracing3 IN-LINE AS/RS PROCESS FOR TWO FUNCTIONS COMBINATIONIn-process begins with tray assembly, most parts take random tray assembly mode when they are delivered to the factory, that is one tray can contain any kinds and any number of parts, arriving order and tray space utility are main consideration factor during this process. Another operation is fixed tray assembly , the parts source can be newly arriving parts or the parts come out from AS/RS. After tray assembly process and barcode scanning the AS/RS unit information will change according to the type of tray code. The detail process is shown in Fig.3. Fixed assembly parts out AS/RS is driven by production plan and emergency requirement. Random assembly parts can not be used in production, the out AS/RS purpose of these parts is for fixed tray assembly operation. So it take conditional query outmode, the process is shown in fig.4.Random tray assembly operationFixed tray assembly operation Barcode scan JudgementFixed tray code Random assembly tray code Change in-status in fixed tray assembly in table and change AS/RS inventory information accordingTo the tray batch code get from this tableChange in-status in random tray assembly in table and change AS/RS inventory information according to the tray batch code get from this tableEnd of in processFig.3 In AS/RS processInput the part code which want to out AS/RSInput the number of the partFind all satisfied AS/RS random assembly part unitsSelect one from above set and out AS/RSFig.4 Random assembly parts out AS/RS process4 CONCLUTIONSThis functional combination solution has been realized in Guangdong Motor Car Factorys material handling system using ORACLE relative database and DEVELOPER/2000 developing tool on WINDOWS platform. Proved by practice, it successfully solves one AS/RS multiple use problem and enhances AS/RSs economy benefits. It has extendable value in many middle and small scale enterprise.References1 Allred J K. Basic of warehouse management system. Material Handling Engineering Directory Issue 1996/19972 虞和谦， 王方智. 现代物流技术与装备国际学术会议讨论综述，.中国机械工程,1995,6(24)3 孙宏昌.ORACLE 应用系统开发工具 . 北京：清华大学出版社， 1995资料译文：用波低温技术生产橡皮粉末的试验装置 高广帆 方耀齐 金良安大连理工大学化学工程系 大连 116012 中国摘要：本篇论文提出了波低温技术生产橡皮粉末的系统。它的主要装置例如波冷冻机、涡旋碾磨机和流动式冷却机已是现成的。同时，它还讨论了关于在干燥器和系统烘干方面所用的硅胶补充的主要技术。并且，它还指出了此系统可能的进展。此技术的制造成本比用液态氮冷却方法成本要低，而且，质量也要好于常温下制粉的质量。波冷冻机有几种性能优于涡轮膨胀机在低温冷冻制粉技术中的应用。关键词：橡皮粉末 碾磨 波冷冻机 试验装置0 引言橡皮粉末是从橡皮擦上被擦掉的组成部分。它可以被直接用作工业生产原料而不需要改进。橡皮粉粒的尺寸越小，橡皮粉末产品的质量越好。其原因是它的特殊表面区域将变得更大和伴随着粉粒尺寸的增加而引起的混合效果将变得更好。常温碾磨和低温碾磨是制造橡皮粉末的两种方法。前一种方法能够进一步分类为干碾磨、湿碾磨和化学碾磨。橡皮粉末的粉粒尺寸通常为2030号。在常温碾磨中，橡皮粉末是受剪切力碾磨出来的。因为加热时间非常长，所以很容易老化，而且质量也容易下降。同时非常低的产量是常温碾磨的另一个不足。在中国，它的生产量仅为4050千克/小时。在低温碾磨中有两种碾磨方法：机械碾磨和涡旋碾磨。橡皮粉末的粉粒尺寸通常为60200号。当橡皮擦的温度低于质化点后，碾磨就通过冲击力来进行。其生产力非常高；粉粒尺寸小，铁丝和纤维几乎完全分开。液态氮和空气致冷方法是得到低温的常用方法。当橡皮擦是免费的和液态氮是很便宜的时候，前一种方法在发达国家才成为可能。大约是每千克橡皮粉末消耗液态氮1.01.5千克/千克.而且在中国每千克液态氮的价格大约为0.4美元.很显然,在中国液态氮的橡皮粉末的生产是不划算的.利用空气冷冻机的橡皮粉末的生产不会引起二次污染.它提供在我们国家橡皮擦再循环利用的途径.直到现在,空气的制冷主要由涡轮膨胀机完成的.这片论文介绍了一种波低温技术生产橡皮粉末的试验系统. 1 工艺规程设计由橡皮擦制造橡皮粉末的试验系统的规程图表如图1所示.一个波冷冻机提供了必要的冷冻了的冷空气.碾磨设备是一台涡轮式碾磨机.橡皮粉粒的冷却和碾磨是间歇循环的操作过程.被往复式空气压缩机1压缩的空气通过油水分离器2,然后进入油过滤器3,在那里,空气里残余的油分子被过滤掉.在容器4里被缓冲和稳定后，空气进入了空气干燥器5.在那里,空气里残余的水分被干燥剂除去.在受压的空气进入波冷冻机7之前,它要在鳍板式热交换器6中进行预冷却.它的温度被穿过激波管机械装置的波冷冻机大大降低.而后,冷空气的流动方向随着不同的操作过程而变化.在橡皮粉粒的冷冻期间,干冷的空气穿过流动式冷却器8、前冷却器10、旋转式鼓风机13和鳍板式热交换器,然后,在回到空气压缩机中继续它的循环.在流动式冷却器中橡皮粉粒的温度降到它的质化点后,碾磨的阶段开始了.从波冷冻机排出的带有一定压力的冷空气呈切线状被喷射到涡旋式碾磨机的空腔内.与此同时,在不同的压力下,橡皮粉粒连续不断地流进涡旋式碾磨机的空腔中被碾磨.待到冷气流流出涡旋式碾磨机,它通过高压和低压旋转分粒机11和12,之后,又受到旋转式鼓 空气流动方向 -橡皮流动方向1. 空气压缩机 2. 油水分离器 3. 油过滤器 4. 空气存贮器5. 空气干燥器6. 鳍板式交换机 7. 波冷冻机 8. 流动式冷却器9. 涡轮式碾磨机10. 前冷却器11. 高压旋转分粒机 12. 低压旋转分粒机 13. 旋转式鼓风机14. 橡皮粉末分类 15. 产品收集 16. 橡皮粉粒风机的压力作用.最后,它又回到空气压缩机经由鳍板式交换器继续它的循环.在进入流动式冷却器之前,在前冷却器中被干燥过的橡皮粉粒吸收了低温气流中的部分能量.在涡旋式碾磨机里被碾磨过的橡皮粉粒分别从涡旋式碾磨机的两个出口进入高压和低压旋转分粒机,并且,在那里累积.终于,橡皮粉粒的分类和收集就完成了.这一系统的工艺过程是一个闭式循环的过程.在这一系统中,空气不断被压缩和冷凝;在循环中,它需要补充的空气是非常小的.它还减轻了净化装置的负担.而且,低温的损失也非常小.气流被高效鳍板式热交换器的最初冷却和橡皮粉粒在前冷却机里的预冷却降低了低温的不可逆的损失.他们都有利于降低橡皮粉末的制造成本.2 主要装置2.1 波冷冻机波冷冻机式一个核心机器.它由一个旋转的喷嘴托盘(通常包括带有会聚气流通道的两个出口)、在喷嘴托盘边缘呈辐射状放置的大量的激波管和其他组成部分例如激波衰减器、封套、中空的旋转轴等所组成.喷嘴的喷射通道不是幅射状的.因此,托盘被剪切力驱动着机械的旋转.此外,如果需要控制旋转速度,可以在轴的尾部安装一个电动机. 喷嘴托盘旋转着通过许多固定的激波管.当某一时间正在旋转的暴露于旋转空气中的喷嘴与某一激波管呈一条直线时,一条移动的激波即在管中形成.在管中的原有气体被不断蔓延的激波加热;热量转换通过管壁进行热能消散.随着喷嘴托盘的旋转,激波管与低压排气管连接在一起.当冷空气被完全排出时,一个新的循环又开始了.排出的冷空气可能是零下120摄氏度,它完全满足了橡皮擦低温碾磨的需要.波冷冻机还有较小的移动部件和耐磨部件、单一的构造、宽大的运转余地.在波冷冻机和涡轮膨胀机的熵效率没什麽不同.但是,它的旋转速度远远低于涡轮膨胀机的旋转速度(他们大约分别是1000转/分和10009000转/分).它的流动速度可能从1103到5.5105立方米/直径.进入的气体压力可能从0.45兆帕到10兆帕.它已经被成功地应用于分离油井气体和从自然气中吸收水分.考虑到它地流动速度和出口温度,它有望于能够用于大规模的橡皮粉末的工业生产.2.2 流动式冷却器流动式冷却器是带有两个端口的圆柱形容器.穿有许多三角形孔的锥形漏斗被安置在较低的端口.一个插头板阀门和一个与涡旋式碾磨机相连的加水管恰好位于漏斗的下面.一条带有很多小孔的环形空气进气管安放在高端和低端的中间部位.通过一条倾斜的加水管道和一个出口阀门以及排气管与前冷却器相连的容器的较高位置就是这一容器的顶端.在橡皮粉粒冷凝的过程中,冷空气从漏斗的小孔以某一速度喷射到容器里.橡皮粉粒处于流动状态,通过对流和大面积的热交换缩短了冷凝的时间.在碾磨期间,从波冷冻机排出的冷空气进入了涡旋式碾磨机.随着插头板阀门的打开,橡皮粉粒在不同气压的作用下流到碾磨机里.阀门的开启频率由粉粒的大小而定.2.3 涡旋式碾磨机从波冷冻机排出的带有一定压力的冷气流给涡旋式碾磨机提供了所需的驱动能量.碾磨机里没有旋转部件.它的核心部件是一个带有在筒壁上安装很多叶片的很短的圆柱形空腔.它的进气喷管是沿切线方向的,并且窄窄的.它也安装在筒壁上.喷管的形状可能是收缩的或是渐缩的.它取决于操作条件.加水管垂直于碾磨机的低部水平线.在管壁有两条排气管的定位先、一个加水管的环形表面和几条窄窄的辐射状狭槽.从进口喷管喷出的冷气流呈辐射状的以高速喷入空腔,并且组成非常强大的涡旋流动区域.在涡旋的中心形成低压.因此,橡皮粉粒被不断地吸进空腔.旋转速率的变化使易碎的橡皮粉粒相互碰撞.而且,在涡旋外面的橡皮粉粒还会与叶片强烈地碰撞.然后,被碾碎的橡皮粉末随着冷气流自动流出空腔.3 工艺说明3.1 干燥剂的补充恢复当干燥剂中的水汽含量大约是时,干燥剂就几乎失效了.因此,在干燥器中的干燥剂的补充恢复是必需的.在试验系统中尤其是在碾磨区域的温度是特别低的.严格控制气流中的水分也是必需的.因此,它装配了两个并联的空气干燥器(如图2).这样可以减小干燥器的直径并平均分配气流.根据诸如空气中水汽含量和碾磨能力之类的条件,在一次操