注塑模课程设计说明书

I/19课程设计说明书题目：盘形塑件注塑模具设计学号：1136230057姓名：娄照君班级：2011级（2）班专业：材料成型及控制工程指导教师：王金芳学院：机械工程学院答辩日期：2011年月日I/19摘要注射成型是将粉状塑料从注射机料斗送人已加热的料筒，经过热熔融后，受柱塞或螺杆的推动，熔融塑料通过料筒前端的喷嘴快速注入闭合塑模中，经冷却定型或加热定型后，开启模具取出制品。此次课程设计主要包括塑件在模具中的成型位置的确定，分型面和型腔数量的确定，浇注系统和浇口的设计，成型零件的设计，脱模机构的设计，冷却系统的设计和模架的选择。协调好各个零件之间的装配关系，用UG造型，用CAD绘制装配图和零件图。整理和编写课程设计说明书。关键词：注射机；模具；注射成型II/19目录第1章塑件的成型工艺析························································41.1塑件的分析···························································41.2ABS的性能分析······················································41.3ABS的注射成型过程及工艺参数········································5第2章拟定模具的结构形式··············································62.1分型面位置的确定······················································62.2型腔数量和排列方式的确定·············································62.3注射机型号的确定····················································6第3章浇注系统的设计···················································83.1主流道的设计······················································83.2分流道的设计·····················································93.3浇口的设计·······················································103.4校核主流道的剪切速率··············································113.5冷料穴的设计及计算················································11第4章成型零件的结构设计及计算········································114.1成型零件的结构设计············································114.2成型零件钢材的选用···········································124.3成型零件工作尺寸的计算·········································124.4成型零件尺寸及动模垫板厚度的计算·····································13第5章模架的确定······················································145.1各模板尺寸的确定···················································145.2模架各尺寸的校核···················································14第6章排气槽的设计··················································14第7章脱模推出机构··················································157.1推出方式的确定······················································157.2推出方式的确定······················································157.3校核推出机构作用在塑件上的单位压应力································157.4推出杆的计算·························································15第8章冷却系统的设计··················································16III/198.1冷却介质····························································168.2冷却系统的简单计算···················································168.3型芯和型腔冷却水道的设置·············································17第9章导向和定位结构的设计············································18参考文献·······································································18附录装配图4/19第1章塑件的成型工艺分析1.1塑件的分析（1）外形尺寸该塑件壁厚2mm，塑件外形尺寸不大，塑料熔体流程不太长，适合于注射成型，如图1-1所示。图1-1盘形塑件（2）精度等级该塑件的精度等级为5级（3）脱模斜度ABS属无定型塑料，成型收缩率较小，因此取该塑件上型芯和凹模的统一脱模斜度为30′～1°1.2ABS的性能分析(1)使用性能综合性能好，冲击强度、力学强度较高，尺寸稳定，耐化学性，电气性能良好；易于成型和机械加工，其表面可镀铬，适合制作一般机械零件、减摩零件、传动零件和结构零（2）成型性能5/191）无定型塑料。其品种很多，各品种的机电性能及成型特性也各有差异，应按品种来确定成型方法及成型条件2）吸湿性强。含水量应小于0.3%（质量），必须充分干燥，要求表面光泽的塑件应要求长时间预热干燥。3）流动性中等。溢边料0.04mm左右。4）模具设计时要注意浇注系统，选择好进料口位置、形式。推出力过大或机械加工时表面呈白色横迹（3）ABS的主要性能指标其性能指标见表1-1所示表1-1ABS的性能指标密度/g·cm31.02～1.08屈服强度/MPa50比体积0.86～0.98拉伸强度/MPa38吸水率（%）0.2～0.4拉伸弹性模量/MPa1.4103熔点/C130～160抗弯强度/MPa80计算收缩率（%）0.4～0.7抗压强度/MPa53比热容/J·（kg·C）1470弯曲弹性模量/MPa1.41031.3ABS的注射成型过程及工艺参数（1）注射成型过程1）成型前的准备。对ABS的色泽、粒度和均匀度等进行检验，由于ABS吸水性较大，成型前应进行充分的干燥。2）注射过程。塑件在注射机料筒内经过加热、塑化达到流动状态后，由模具的浇注系统进入模具型腔进行成型，其过程可分为冲模、压实、保压、倒流和冷却五个阶段。3）塑件的后处理。处理的介质为空气和水，处理温度为60～75C，处理时间为16～20s。（2）注射工艺参数1）注射机成型：螺旋式，螺杆转数为30r/min。2）料筒温度（C）:后段150～170；中段165～180；前段180～200。3）喷嘴温度（C）：170～180。4）模具温度（C）：50～80。5）注射压力机（MPa）:60～100。6）成型时间（s）:30(注射时间取1.6.冷却时间20.4，辅助时间8)6/19第2章拟定模具的结构形式2.1分型面位置的确定通过对塑件的结构形式的分析，分型面应选在端盖截面积最大且利于开模取出塑件的底平面上，其位置如图2-1所示。图2-1分型面2.2型腔数量和排列方式的确定（1）型腔数量的确定该塑件采用的精度等级为5级，且为大批量生产，可采取一模多腔的结构形式。同时，考虑到塑件尺寸、模具结构尺寸的大小关系，以及制造费用和各种成本费等因素，初步定为一模两腔结构形式。（2）型腔排列形式的确定多型腔模具尽可能采用平衡式排列布置，且要力求紧凑，并与浇口开设的部位对称。由于该设计选择的是一模两腔，故采用直线对称排列，如图2-2所示。（3）模具结构形式的确定从上面的分析可知，本模具设计为一模两腔，对称直线排列，根据塑件结构形状，推出机构拟采用脱模板推出的推出形式。注射系统设计的时，流道采用平衡式，浇口采用侧浇口，且开设在分型面上。因此，定模部分不需要单独开设分型面取出凝料，动模部分需要添加型芯固定板、支撑板和脱模板。由上综分析可确定选用带脱模板的但分型面注射模。2.3注射机型号的确定（1）注射量的计算通过三维软件建模设计分析计算得塑件体积：3832.14cmV塑塑件质量：ggVm7.4802.183.14塑塑7/19式中，3/02.11-1cmg可取参考表。（2）注射系统凝料体积的初步估算注射系统的凝料在设计之前是不能确定准确的数值，但是可以根据经验按照塑件体积的0.2～1倍来估算，故一次注入模具型腔塑料熔体的总体积（即浇注系统的凝料和塑件体积之和）为3360.3522.1832.1422.01cmcmVV）（塑总（3）选择注射机根据第二步计算得出一次注入模具型腔的塑料总质量360.35cmV总，并结合式335.448.0/60.358.0/8.0/cmcmVVV总总公则有：。根据以上的计算，初步选定公称注射量为1003cm，注射机型号为SZ-60/40，其主要技术参数见表2-1。表2-1注射机主要技术参数理论注射量/3cm100移模行程/mm260螺杆柱塞直径/mmV注射压力/MPa35最大模具厚度/mm340150最小模具厚度/mm10锁模力/kN600喷嘴球半径/mm12拉杆内间距/mm440340喷嘴口孔径/mm4(4)注射机的相关参数的校核1）注射压力校核。查表可知，ABS所需注射压力为80～110MPa，这里取25.115010010kMPapMPap，注射压力安全系数压力，该注射机的公称注射公～1.4，这里取3.11k，则1301003.101pk＜公p，所以，注射机注射压力合格。2）锁模力校核a、塑件在分型面上的投影面积22225513)684(4mmmmA塑b、浇注系统在分型面上的投影面上的投影面积浇A，即流道凝料（包括浇口）在分型面上的投影面积浇A数值，可以按照多型腔模的统计分析来确定。浇A是每个塑件在分型面上的投影面积塑A的0.2～0.5倍。由于本流道设计简单，分流道相对较短，因此流道凝料投影面积可以适当取8/19小一些。这里取浇A=0.2塑A。c、塑件和浇注系统在分型面上总的投影面积总A，则总A=222.1323155132.122.12)2.0(mmmmAAAn塑塑塑d、模具型腔内的胀型力胀F，则胀F=总AkNNNp092.463463092352.13231模式中，模p是型腔的平均计算压力值。模p是模具型腔内的压力，通常取注射压力的20%～40%，大致范围是25～40MPa。对于粘度较大的精度较高的塑料制品应取较大值。ABS属中等粘度塑料及有精度要求的塑件，故模p取35MPa。