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首页 电路板焊接工艺

电路板焊接工艺.doc

电路板焊接工艺

yu燕苹
2017-09-18 0人阅读 举报 0 0 暂无简介

简介:本文档为《电路板焊接工艺doc》,可适用于综合领域

电路板焊接工艺PCB应制电路板焊接工艺PCB板焊接的工艺流程PCB板焊接工艺流程介绍PCB板焊接过程中需手工插件、手工焊接、修理和检验。PCB板焊接的工艺流程按清单归类元器件插件焊接剪脚检查修整。PCB板焊接的工艺要求元器件加工处理的工艺要求元器件在插装之前必须对元器件的可焊接性进行处理若可焊性差的要先对元器件引脚镀锡。元器件引脚整形后其引脚间距要求与PCB板对应的焊盘孔间距一致。元器件引脚加工的形状应有利于元器件焊接时的散热和焊接后的机械强度。元器件在PCB板插装的工艺要求元器件在PCB板插装的顺序是先低后高先小后大先轻后重先易后难先一般元器件后特殊元器件且上道工序安装后不能影响下道工序的安装。元器件插装后其标志应向着易于认读的方向并尽可能从左到右的顺序读出。有极性的元器件极性应严格按照图纸上的要求安装不能错装。元器件在PCB板上的插装应分布均匀排列整齐美观不允许斜排、立体交叉和重叠排列不允许一边高一边低也不允许引脚一边长一边短。PCB板焊点的工艺要求焊点的机械强度要足够焊接可靠保证导电性能焊点表面要光滑、清洁PCB板焊接过程的静电防护静电防护原理对可能产生静电的地方要防止静电积累采取措施使之控制在安全范围内。对已经存在的静电积累应迅速消除掉即时释放。静电防护方法泄漏与接地。对可能产生或已经产生静电的部位进行接地提供静电释放通道。采用埋地线的方法建立“独立”地线。非导体带静电的消除:用离子风机产生正、负离子可以中和静电源的静电。电子元器件的插装implementationofcorrectivetasksforthenewproblemsfoundinatimelymannerintothespecialrectificationandrectificationcategoryIndepthsummaryofgoodpracticesandgoodexperienceineducationalpractice,goodaroundthetypical,continuetopromotetherectification,topreventrepeatedrebound,useoftheresultsoftheactivities,timelyorganizationlookbackagainThetheoreticalresults,continuouslyconrests,intheimplementationofthedecisionandtask,andeventheexistenceof"donotwanttodo,wanttodosuchabacklashandcopewiththenegative,使用合适的助焊剂。,具有适当的焊接温度。,具有合适的焊接时间手工焊接的方法电烙铁与焊锡丝的握法手工焊接握电烙铁的方法有反握、正握及握笔式三种下图是两种焊锡丝的拿法手工焊接的步骤,准备焊接。清洁焊接部位的积尘及污渍、元器件的插装、导线与接线端钩连为焊接做好前期的预备工作。,加热焊接。将沾有少许焊锡的电烙铁头接触被焊元器件约几秒钟。若是要拆下PCB板上的元器件则待烙铁头加热后用手或镊子轻轻拉动元器件看是否可以取下。,清理焊接面。若所焊部位焊锡过多可将烙铁头上的焊锡甩掉(注意不要烫伤皮肤,也不要甩到PCB板上)然后用烙铁头“沾”些焊锡出来。若焊点焊锡过少、不圆滑时可以用电烙铁头“蘸”些焊锡对焊点进行补焊。,检查焊点。看焊点是否圆润、光亮、牢固是否有与周围元器件连焊的现象。手工焊接的方法,加热焊件。恒温烙铁温度一般控制在至之间焊接时间控制在秒以内。部分原件的特殊焊接要求:implementationofcorrectivetasksforthenewproblemsfoundinatimelymannerintothespecialrectificationandrectificationcategoryIndepthsummaryofgoodpracticesandgoodexperienceineducationalpractice,goodaroundthetypical,continuetopromotetherectification,topreventrepeatedrebound,useoftheresultsoftheactivities,timelyorganizationlookbackagainThetheoreticalresults,continuouslyconsolidateanddeepenandexpandeducationalpracticetoachievethesystemresults,practicalresultsThree,themainproblemsandrectificationmeasuresfocusonrectificationgoals,determinedtohonorthecommitmentrectificationmeasurestobuildlongtermmechanismstyleconstructionbureauParty,improvetheideologicalstyleTheconstructionandworkinglevel,accordingtothelistofissuestosortitout,withoverallrequirementstocarryoutthemasslineofeducationalactivities,focusontheimplementationoftherectification,enhanceteamabilitytodiscoverandsolvetheirownproblems,focusonbuildingapoliticalfirm,pioneeringandinnovative,wholeheartedlyforthepeople,striveforunity,harmony,strongcollectiveleadership(ahonestandclean)therelackofglobalawarenessandinnovationproblemincarryingoutthedemocraticcentralismofthepartyThepartywilldiscussthemainpointsoftheBureauofsafetyproductionandinternalfunctionalcomponentsinthelaborbureauheldabureauandexecutive,anddiscussspecificpersonnelin,majorcapitalspendingNo,strictlyimplementthedecisionproceduresof"threemajor"matters"collectiveleadership,democraticcentralism,individualconsultations,themeetingdecidedtheworkingprincipleofthetightloose,notverygoodtoplaytheroleofallmembersoftheleadershipteam,intheglobalconsultationisnotenough,didnotfullyconsidertheactualsituationoftheindividual,butbytheexecutivesure,thelackofdemocracyindifferentopinionsfullydiscussedanddemonstratedInrelationtopersonaladjustmentandthefunctionalgroupwork,individualpartymembersandcadresarenotgoodputforwardtheirviewsandopinions,ordaretoexpresstheirviews,thecrowd,thelackofglobalawarenessandsenseofinnovationSomeleadingcadresaretoostrongAdjustthelocalandlocalinterests,thetendencytoignoretheoverallinterests,focusonimmediateinterestsandlocalinterests,intheimplementationofthedecisionandtask,andeventheexistenceof"donotwanttodo,wanttodosuchabacklashandcopewiththenegative项目器件SMD器件DIP器件焊接时烙铁头温度:焊接时间:每个焊点至秒至秒拆除时烙铁头温度:至备注:根据CHIP件尺寸不同请当焊接大功率(TO、TO、使用不同的烙铁嘴TO等封装)或焊点与大铜箔相连上述温度无法焊接时烙铁温度可升高至当焊接敏感怕热零件(LED、CCD、传感器等)温度控制在至焊接时烙铁头与PCB板成角电烙铁头顶住焊盘和元器件引脚然后给元器件引脚和焊盘均匀预热。,移入焊锡丝。焊锡丝从元器件脚和烙铁接触面处引入焊锡丝应靠在元器件脚与烙铁头之间。,移开焊锡。当焊锡丝熔化(要掌握进锡速度)焊锡散满整个焊盘时即可以角方向拿开焊锡丝。,移开电烙铁。焊锡丝拿开后烙铁继续放在焊盘上持续,,,秒当焊锡只有轻微烟雾冒出时即可拿开烙铁拿开烙铁时不要过于迅速或用力往上挑以免溅落锡珠、锡点、或使焊锡点拉尖等同时要保证被焊元器件在焊锡凝固之前不要移动或受到震动否则极易造成焊点结构疏松、虚焊等现象。导线和接线端子的焊接常用连接导线,单股导线。,多股导线。,屏蔽线。导线焊前处理,剥绝缘层导线焊接前要除去末端绝缘层。拨出绝缘层可用普通工具或专用工具。用剥线钳或普通偏口钳剥线时要注意对单股线不应伤及导线多股线及屏蔽线不断线否则将影响接头质量。对多股线剥除绝缘层时注意将线芯拧成螺旋状一般采用边拽边拧的方式。,预焊implementationofcorrectivetasksforthenewproblemsfoundinatimelymannerintothespecialrectificationandrectificationcategoryIndepthsummaryofgoodpracticesandgoodexperienceineducationalpractice,goodaroundthetypical,continuetopromotetherectification,topreventrepeatedrebound,useoftheresultsoftheactivities,timelyorganizationlookbackagainThetheoreticalresults,continuouslyconsolidateanddeepenandexpandeducationalpracticetoachievethesystemresults,practicalresultsThree,themainproblemsandrectificationmeasuresfocusonrectificationgoals,determinedtohonorthecommitmentrectificationmeasurestobuildlongtermmechanismstyleconstructionbureauParty,improvetheideologicalstyleTheconstructionandworkinglevel,accordingtothelistofissuestosortitout,withoverallrequirementstocarryoutthemasslineofeducationalactivities,focusontheimplementationoftherectification,enhanceteamabilitytodiscoverandsolvetheirownproblems,focusonbuildingapoliticalfirm,pioneeringandinnovative,wholeheartedlyforthepeople,striveforunity,harmony,strongcollectiveleadership(ahonestandclean)therelackofglobalawarenessandinnovationproblemincarryingoutthedemocraticcentralismofthepartyThepartywilldiscussthemainpointsoftheBureauofsafetyproductionandinternalfunctionalcomponentsinthelaborbureauheldabureauandexecutive,anddiscussspecificpersonnelin,majorcapitalspendingNo,strictlyimplementthedecisionproceduresof"threemajor"matters"collectiveleadership,democraticcentralism,individualconsultations,themeetingdecidedtheworkingprincipleofthetightloose,notverygoodtoplaytheroleofallmembersoftheleadershipteam,intheglobalconsultationisnotenough,didnotfullyconsidertheactualsituationoftheindividual,butbytheexecutivesure,thelackofdemocracyindifferentopinionsfullydiscussedanddemonstratedInrelationtopersonaladjustmentandthefunctionalgroupwork,individualpartymembersandcadresarenotgoodputforwardtheirviewsandopinions,ordaretoexpresstheirviews,thecrowd,thelackofglobalawarenessandsenseofinnovationSomeleadingcadresaretoostrongAdjustthelocalandlocalinterests,thetendencytoignoretheoverallinterests,focusonimmediateinterestsandlocalinterests,intheimplementationofthedecisionandtask,andeventheexistenceof"donotwanttodo,wanttodosuchabacklashandcopewiththenegative预焊是导线焊接的关键步骤。导线的预焊又称为挂锡但注意导线挂锡时要边上锡边旋转旋转方向与拧合方向一致多股导线挂锡要注意“烛心效应”即焊锡浸入绝缘层内造成软线变硬容易导致接头故障。导线和接线端子的焊接,绕焊绕焊把经过上锡的导线端头在接线端子上缠一圈用钳子拉紧缠牢后进行焊接绝缘层不要接触端子导线一定要留,mm为宜。,钩焊钩焊是将导线端子弯成钩形钩在接线端子上并用钳子夹紧后施焊。,搭焊搭焊把经过镀锡的导线搭到接线端子上施焊。绕焊钩焊搭焊PCB板上的焊接PCB板焊接的注意事项电烙铁一般应选内热式,W或调温式烙铁的温度不超过的为宜。烙铁头形状应根据PCB板焊盘大小采用截面式或尖嘴式目前PCB板发展趋势是小型密集化因此一般常用小型尖嘴式烙铁头。加热时应尽量使烙铁头同时接触印制板上铜箔和元器件引脚对较大的焊盘(直径大于mm)焊接时可移动烙铁即烙铁绕焊盘转动以免长时间停留一点导致局部过热。金属化孔的焊接。焊接时不仅要让焊料润湿焊盘而且孔内也要润湿填充。因此金属化孔加热时间应长于单面板implementationofcorrectivetasksforthenewproblemsfoundinatimelymannerintothespecialrectificationandrectificationcategoryIndepthsummaryofgoodpracticesandgoodexperienceineducationalpractice,goodaroundthetypical,continuetopromotetherectification,topreventrepeatedrebound,useoftheresultsoftheactivities,timelyorganizationlookbackagainThetheoreticalresults,continuouslyconsolidateanddeepenandexpandeducationalpracticetoachievethesystemresults,practicalresultsThree,themainproblemsandrectificationmeasuresfocusonrectificationgoals,determinedtohonorthecommitmentrectificationmeasurestobuildlongtermmechanismstyleconstructionbureauParty,improvetheideologicalstyleTheconstructionandworkinglevel,accordingtothelistofissuestosortitout,withoverallrequirementstocarryoutthemasslineofeducationalactivities,focusontheimplementationoftherectification,enhanceteamabilitytodiscoverandsolvetheirownproblems,focusonbuildingapoliticalfirm,pioneeringandinnovative,wholeheartedlyforthepeople,striveforunity,harmony,strongcollectiveleadership(ahonestandclean)therelackofglobalawarenessandinnovationproblemincarryingoutthedemocraticcentralismofthepartyThepartywilldiscussthemainpointsoftheBureauofsafetyproductionandinternalfunctionalcomponentsinthelaborbureauheldabureauandexecutive,anddiscussspecificpersonnelin,majorcapitalspendingNo,strictlyimplementthedecisionproceduresof"threemajor"matters"collectiveleadership,democraticcentralism,individualconsultations,themeetingdecidedtheworkingprincipleofthetightloose,notverygoodtoplaytheroleofallmembersoftheleadershipteam,intheglobalconsultationisnotenough,didnotfullyconsidertheactualsituationoftheindividual,butbytheexecutivesure,thelackofdemocracyindifferentopinionsfullydiscussedanddemonstratedInrelationtopersonaladjustmentandthefunctionalgroupwork,individualpartymembersandcadresarenotgoodputforwardtheirviewsandopinions,ordaretoexpresstheirviews,thecrowd,thelackofglobalawarenessandsenseofinnovationSomeleadingcadresaretoostrongAdjustthelocalandlocalinterests,thetendencytoignoretheoverallinterests,focusonimmediateinterestsandlocalinterests,intheimplementationofthedecisionandtask,andeventheexistenceof"donotwanttodo,wanttodosuchabacklashandcopewiththenegative焊接时不要用烙铁头摩擦焊盘的方法增强焊料润湿性能而要靠表面清理和预焊。PCB板的焊接工艺焊前准备按照元器件清单检查元器件型号、规格及数量是否符合要求。焊接人员带防静电手腕确认恒温烙铁接地。装焊顺序元器件的装焊顺序依次是电阻器、电容器、二极管、三极管、集成电路、大功率管其它元器件是先小后大。对元器件焊接的要求,电阻器的焊接。按元器件清单将电阻器准确地装入规定位置并要求标记向上字向一致。装完一种规格再装另一种规格尽量使电阻器的高低一致。焊接后将露在PCB板表面上多余的引脚齐根剪去。,电容器的焊接。将电容器按元器件清单装入规定位置并注意有极性的电容器其“”与“,”极不能接错。电容器上的标记方向要易看得见。先装玻璃釉电容器、金属膜电容器、瓷介电容器最后装电解电容器。,二极管的焊接。正确辨认正负极后按要求装入规定位置型号及标记要易看得见。焊接立式二极管时对最短的引脚焊接时时间不要超过秒钟。,三极管的焊接。按要求将e、b、c三根引脚装入规定位置。焊接时间应尽可能的短些焊接时用镊子夹住引脚以帮助散热。焊接大功率三极管时若需要加装散热片应将接触面平整、光滑后再紧固。,集成电路的焊接。将集成电路插装在线路板上按元器件清单要求检查集成电路的型号、引脚位置是否符合要求。焊接时先焊集成电路边沿的二只引脚以使其定位然后再从左到右或从上至下进行逐个焊接。焊接时烙铁一次沾取锡量为焊接~只引脚的量烙铁头先接触印制电路的铜箔待焊锡进入集成电路引脚底部时烙铁头再接触引脚接触时间以不超过秒钟为宜而且要使焊锡均匀包住引脚。焊接完毕后要查一下是否有漏焊、碰焊、虚焊之处并清理焊点处的焊料。implementationofcorrectivetasksforthenewproblemsfoundinatimelymannerintothespecialrectificationandrectificationcategoryIndepthsummaryofgoodpracticesandgoodexperienceineducationalpractice,goodaroundthetypical,continuetopromotetherectification,topreventrepeatedrebound,useoftheresultsoftheactivities,timelyorganizationlookbackagainThetheoreticalresults,continuouslyconsolidateanddeepenandexpandeducationalpracticetoachievethesystemresults,practicalresultsThree,themainproblemsandrectificationmeasuresfocusonrectificationgoals,determinedtohonorthecommitmentrectificationmeasurestobuildlongtermmechanismstyleconstructionbureauParty,improvetheideologicalstyleTheconstructionandworkinglevel,accordingtothelistofissuestosortitout,withoverallrequirementstocarryoutthemasslineofeducationalactivities,focusontheimplementationoftherectification,enhanceteamabilitytodiscoverandsolvetheirownproblems,focusonbuildingapoliticalfirm,pioneeringandinnovative,wholeheartedlyforthepeople,striveforunity,harmony,strongcollectiveleadership(ahonestandclean)therelackofglobalawarenessandinnovationproblemincarryingoutthedemocraticcentralismofthepartyThepartywilldiscussthemainpointsoftheBureauofsafetyproductionandinternalfunctionalcomponentsinthelaborbureauheldabureauandexecutive,anddiscussspecificpersonnelin,majorcapitalspendingNo,strictlyimplementthedecisionproceduresof"threemajor"matters"collectiveleadership,democraticcentralism,individualconsultations,themeetingdecidedtheworkingprincipleofthetightloose,notverygoodtoplaytheroleofallmembersoftheleadershipteam,intheglobalconsultationisnotenough,didnotfullyconsidertheactualsituationoftheindividual,butbytheexecutivesure,thelackofdemocracyindifferentopinionsfullydiscussedanddemonstratedInrelationtopersonaladjustmentandthefunctionalgroupwork,individualpartymembersandcadresarenotgoodputforwardtheirviewsandopinions,ordaretoexpresstheirviews,thecrowd,thelackofglobalawarenessandsenseofinnovationSomeleadingcadresaretoostrongAdjustthelocalandlocalinterests,thetendencytoignoretheoverallinterests,focusonimmediateinterestsandlocalinterests,intheimplementationofthedecisionandtask,andeventheexistenceof"donotwanttodo,wanttodosuchabacklashandcopewiththenegative焊接质量的分析及拆焊焊接的质量分析构成焊点虚焊主要有下列几种原因:,被焊件引脚受氧化,被焊件引脚表面有污垢,焊锡的质量差,焊接质量不过关焊接时焊锡用量太少,电烙铁温度太低或太高焊接时间过长或太短,焊接时焊锡未凝固前焊件抖动。手工焊接质量分析手工焊接常见的不良现象焊点缺陷外观特点危害原因分析焊锡与元器件引脚(元器件引脚未清洁好、未和铜箔之间有明显设备时好时坏工镀好锡或锡氧化黑色界限焊锡向界作不稳定(印制板未清洁好喷涂的限凹陷助焊剂质量不好虚焊浪费焊料可能包焊点表面向外凸出焊丝撤离过迟藏缺陷焊料过多(焊锡流动性差或焊锡撤离焊点面积小于焊盘过早的焊料未形成机械强度不足(助焊剂不足平滑的过渡面(焊接时间太短焊料过少焊点缺陷外观特点危害原因分析焊点发白表面较粗焊盘强度降低容烙铁功率过大加热时间过长糙无金属光泽易剥落过热表面呈豆腐渣状颗强度低导电性能焊料未凝固前焊件抖动粒可能有裂纹不好冷焊implementationofcorrectivetasksforthenewproblemsfoundinatimelymannerintothespecialrectificationandrectificationcategoryIndepthsummaryofgoodpracticesandgoodexperienceineducationalpractice,goodaroundthetypical,continuetopromotetherectification,topreventrepeatedrebound,useoftheresultsoftheactivities,timelyorganizationlookbackagainThetheoreticalresults,continuouslyconsolidateanddeepenandexpandeducationalpracticetoachievethesystemresults,practicalresultsThree,themainproblemsandrectificationmeasuresfocusonrectificationgoals,determinedtohonorthecommitmentrectificationmeasurestobuildlongtermmechanismstyleconstructionbureauParty,improvetheideologicalstyleTheconstructionandworkinglevel,accordingtothelistofissuestosortitout,withoverallrequirementstocarryoutthemasslineofeducationalactivities,focusontheimplementationoftherectification,enhanceteamabilitytodiscoverandsolvetheirownproblems,focusonbuildingapoliticalfirm,pioneeringandinnovative,wholeheartedlyforthepeople,striveforunity,harmony,strongcollectiveleadership(ahonestandclean)therelackofglobalawarenessandinnovationproblemincarryingoutthedemocraticcentralismofthepartyThepartywilldiscussthemainpointsoftheBureauofsafetyproductionandinternalfunctionalcomponentsinthelaborbureauheldabureauandexecutive,anddiscussspecificpersonnelin,majorcapitalspendingNo,strictlyimplementthedecisionproceduresof"threemajor"matters"collectiveleadership,democraticcentralism,individualconsultations,themeetingdecidedtheworkingprincipleofthetightloose,notverygoodtoplaytheroleofallmembersoftheleadershipteam,intheglobalconsultationisnotenough,didnotfullyconsidertheactualsituationoftheindividual,butbytheexecutivesure,thelackofdemocracyindifferentopinionsfullydiscussedanddemonstratedInrelationtopersonaladjustmentandthefunctionalgroupwork,individualpartymembersandcadresarenotgoodputforwardtheirviewsandopinions,ordaretoexpresstheirviews,thecrowd,thelackofglobalawarenessandsenseofinnovationSomeleadingcadresaretoostrongAdjustthelocalandlocalinterests,thetendencytoignoretheoverallinterests,focusonimmediateinterestsandlocalinterests,intheimplementationofthedecisionandtask,andeventheexistenceof"donotwanttodo,wanttodosuchabacklashandcopewiththenegative(助焊剂过少而加热时间过外观不佳容易造长焊点出现尖端成桥连短路(烙铁撤离角度不当拉尖(焊锡过多相邻导线连接电气短路(烙铁撤离角度不当桥连铜箔从印制板上剥印制PCB板已被损焊接时间太长温度过高离坏铜箔翘起拆焊工具在拆卸过程中主要用的工具有:电烙铁、吸锡器、镊子等。拆卸方法,引脚较少的元器件拆法:一手拿着电烙铁加热待拆元器件引脚焊点一手用镊子夹着元器件待焊点焊锡熔化时用夹子将元器件轻轻往外拉。,多焊点元器件且引脚较硬的元器件拆法:采用吸锡器逐个将引脚焊锡吸干净后再用夹子取出元器件如图。,双列或四列IC的拆卸用热风枪拆焊温度控制在C风量控制在,格对着引脚垂直、均匀的来回吹热风同时用镊子的尖端靠在集成电路的一个角上待所有引脚焊锡熔化时用镊子尖轻轻将IC挑起。检验采用目测检验焊点外观并可借助,倍放大镜。合格焊点的判定:只有符合下列要求的焊点才能判定为合格焊点。a(焊点表面光滑、明亮无针孔或非结晶状态b(焊料应润湿所有焊接表面形成良好的焊锡轮廓线润湿角一般应小于c焊料应充分覆盖所有连接部位但应略显导线或引线外形轮廓焊料不足或过量都是不允许的d(焊点和连接部位不应有划痕、尖角、针孔、砂眼、焊剂残渣、焊料飞溅物及其它异物e(焊料不应呈滴状、尖峰状相邻导电体间不应发生桥接f焊料或焊料与连接件之间不应存在裂缝、断裂或分离implementationofcorrectivetasksforthenewproblemsfoundinatimelymannerintothespecialrectificationandrectificationcategoryIndepthsummaryofgoodpracticesandgoodexperienceineducationalpractice,goodaroundthetypical,continuetopromotetherectification,topreventrepeatedrebound,useoftheresultsoftheactivities,timelyorganizationlookbackagainThetheoreticalresults,continuouslyconsolidateanddeepenandexpandeducationalpracticetoachievethesystemresults,practicalresultsThree,themainproblemsandrectificationmeasuresfocusonrectificationgoals,determinedtohonorthecommitmentrectificationmeasurestobuildlongtermmechanismstyleconstructionbureauParty,improvetheideologicalstyleTheconstructionandworkinglevel,accordingtothelistofissuestosortitout,withoverallrequirementstocarryoutthemasslineofeducationalactivities,focusontheimplementationoftherectification,enhanceteamabilitytodiscoverandsolvetheirownproblems,focusonbuildingapoliticalfirm,pioneeringandinnovative,wholeheartedlyforthepeople,striveforunity,harmony,strongcollectiveleadership(ahonestandclean)therelackofglobalawarenessandinnovationproblemincarryingoutthedemocraticcentralismofthepartyThepartywilldiscussthemainpointsoftheBureauofsafetyproductionandinternalfunctionalcomponentsinthelaborbureauheldabureauandexecutive,anddiscussspecificpersonnelin,majorcapitalspendingNo,strictlyimplementthedecisionproceduresof"threemajor"matters"collectiveleadership,democraticcentralism,individualconsultations,themeetingdecidedtheworkingprincipleofthetightloose,notverygoodtoplaytheroleofallmembersoftheleadershipteam,intheglobalconsultationisnotenough,didnotfullyconsidertheactualsituationoftheindividual,butbytheexecutivesure,thelackofdemocracyindifferentopinionsfullydiscussedanddemonstratedInrelationtopersonaladjustmentandthefunctionalgroupwork,individualpartymembersandcadresarenotgoodputforwardtheirviewsandopinions,ordaretoexpresstheirviews,thecrowd,thelackofglobalawarenessandsenseofinnovationSomeleadingcadresaretoostrongAdjustthelocalandlocalinterests,thetendencytoignoretheoverallinterests,focusonimmediateinterestsandlocalinterests,intheimplementationofthedecisionandtask,andeventheexistenceof"donotwanttodo,wanttodosuchabacklashandcopewiththenegativeg(不应存在冷焊或过热连接h(印制电路板、导线绝缘层和元器件不应过热焦化发黑。印制电路板基材不应分层起泡印制导线和焊盘不应分离起翘。焊点返工对有缺陷的焊点允许返工每个焊点的返工次数不得超过三次。对以下类型的焊点缺陷可以对焊点重熔必要时可添加焊剂和焊料。a(焊料不足或过量b(冷焊点c(焊点裂纹或焊点位移d(焊料润湿不良e(焊点表面有麻点、孔或空洞f连接处母材金属暴露g(焊点拉尖、桥接。需解焊后重新焊接的焊点返工应符合本标准和QJ的要求。经返工的焊点均应符合本标准及相关标准的技术要求并重新检验。焊接后的处理焊接后要注意检查以下几点:检查有无漏焊、错焊(极性焊反)、短路、虚焊等现象。检查焊点是否有适当的焊料表面是否具有良好的光泽且均匀不应有毛刺、间隙及裂纹焊点表面要清洁。要正确使用洗板水清理PCB板上的残留物如:锡渣、锡碎、元件脚等。使用人员应做好保护措施洗板水具有挥发性、可燃性用剩的应装好、摆放好不要浪费洗板水。通电检测:先用万用表电阻挡测量电源输入端看是否有短路现象。如有应在加电前排除。根据原理图分别对电路模块进行电路检查如有疑问可以请教工程师。通电完成后必须按清单装配好IC检查无误。检查好的PCBA应马上用静电袋包装好不能随意摆放。implementationofcorrectivetasksforthenewproblemsfoundinatimelymannerintothespecialrectificationandrectificationcategoryIndepthsummaryofgoodpracticesandgoodexperienceineducationalpractice,goodaroundthetypical,continuetopromotetherectification,topreventrepeatedrebound,useoftheresultsoftheactivities,timelyorganizationlookbackagainThetheoreticalresults,continuouslyconsolidateanddeepenandexpandeducationalpracticetoachievethesystemresults,practicalresultsThree,themainproblemsandrectificationmeasuresfocusonrectificationgoals,determinedtohonorthecommitmentrectificationmeasurestobuildlongtermmechanismstyleconstructionbureauParty,improvetheideologicalstyleTheconstructionandworkinglevel,accordingtothelistofissuestosortitout,withoverallrequirementstocarryoutthemasslineofeducationalactivities,focusontheimplementationoftherectification,enhanceteamabilitytodiscoverandsolvetheirownproblems,focusonbuildingapoliticalfirm,pioneeringandinnovative,wholeheartedlyforthepeople,striveforunity,harmony,strongcollectiveleadership(ahonestandclean)therelackofglobalawarenessandinnovationproblemincarryingoutthedemocraticcentralismofthepartyThepartywilldiscussthemainpointsoftheBureauofsafetyproductionandinternalfunctionalcomponentsinthelaborbureauheldabureauandexecutive,anddiscussspecificpersonnelin,majorcapitalspendingNo,strictlyimplementthedecisionproceduresof"threemajor"matters"collectiveleadership,democraticcentralism,individualconsultations,themeetingdecidedtheworkingprincipleofthetightloose,notverygoodtoplaytheroleofallmembersoftheleadershipteam,intheglobalconsultationisnotenough,didnotfullyconsidertheactualsituationoftheindividual,butbytheexecutivesure,thelackofdemocracyindifferentopinionsfullydiscussedanddemonstratedInrelationtopersonaladjustmentandthefunctionalgroupwork,individualpartymembersandcadresarenotgoodputforwardtheirviewsandopinions,ordaretoexpresstheirviews,thecrowd,thelackofglobalawarenessandsenseofinnovationSomeleadingcadresaretoostrongAdjustthelocalandlocalinterests,thetendencytoignoretheoverallinterests,focusonimmediateinterestsandlocalinterests,intheimplementationofthedecisionandtask,andeventheexistenceof"donotwanttodo,wanttodosuchabacklashandcopewiththenegativ
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