统计制程品管(SPC).pptx
K在内之或然率在外之或然率0.6750.00%50.00%168.26%31.74%1.9695.00%5.00%295.45%4.55%2.5899.00%1.00%399.73%0.27%-30.2-20.7-11.62.3+11.6+20.7+30.20.05-3-2-1+1+2+399.73%95.45%68.26%-3+3UCLCLLCL00.20.71.62.31.60.70.2000.20.71.62.31.60.70.2000.20.71.62.31.60.70.2000.20.71.62.31.60.70.20大小预测时间00.10.537730.50.10000.020.050.10.170.250.350.450.450.350.20.0800.050.10.150.20.250.250.20.150.10.050.02000.20.71.62.31.60.70.2000.10.53730.50.10大小预测时间00.21.22.432.41.20.2000.21.22.432.41.20.20-31+32管制界限管制界限值值1 2 3 431.74%4.56%0.27%6/103%平均值移动平均值移动1值值1 2 3 497.72%84.13%50.00%15.87%2.28%15.87%50.11%84.13%通常会牵涉到消除产生变异的特殊原因可以由制程人员直接加以改善大约能够解决15%之制程上之问题通常必须改善造成变异的共同问题经常需要管理阶层的努力与对策大约85%的问题是属于此类系统 建立可解决问题之系统建立可解决问题之系统确认关键制程及特性确认关键制程及特性导入导入SPCSPC进行关键进行关键制程及特性之管制制程及特性之管制检讨制程能力检讨制程能力符合规格程序符合规格程序持续进行制程改善计划持续进行制程改善计划导入导入SPCSPC进行关键进行关键制程及特性之管制制程及特性之管制提报及提报及执行制执行制程改善计划程改善计划决定管制项目决定管制项目决定管制目标决定管制目标决定抽样方法决定抽样方法选用管制图的格式选用管制图的格式记入记入管制界限管制界限绘绘点、实施点、实施重新检讨管制图重新检讨管制图处置措施处置措施管制图判读管制图判读管管 制制 图图 的的 选选 择择数据性质?数据性质?数据系不良数数据系不良数或缺点数或缺点数样本大小样本大小 n=?n=? n是否相等?是否相等?单位大小单位大小是否相关是否相关u管管制制图图C管管制制图图P P管管制制图图PnPn管管制制图图CL 性质?性质?X-Rm管管制制图图n =?=?X-X-管管制制图图X-RX-R管管制制图图X-RX-R管管制制图图计量值计数值 n 2 n = 1不是缺点数是不是是 X X n 10 n = 2 5 n = 3或5 制品名称:紫铜管 品质特性:内径 测定单位:m/m 制造场所:XXX机械号码:XXX 操 作 者 :XXX 测 定 者 :XXX 抽样期限:自 年 月 日 至 年 月 日样组测定值XR样组测定值XRX1X2X3X4X5X1X2X3X4X512345678910111213504746504650474850495150495053454848494950505150504949534949505250464951494949524548495451484951464652505150495250545251534850515550.449.647.449.649.651.249.248.850.649.049.250.450.4384485554553614151617181920212223242553534650505250525550475348485052494947495454515147495349505250515152515152515149495353535150525051525349515052505049525150.250.650.649.849.851.250.451.052.251.050.651.21.2546573246455531201 1、将每样组之、将每样组之 X X 与与 R R 算出记入数据表内。算出记入数据表内。2 2、求、求 X X 与与 R R X = = = 50.16 X = = = 50.16 R = = = 4.8 R = = = 4.83 3、查系数查系数A A2 2,D D4 4,D D3 3 A A2 2 = 0.58 = 0.58 ,D D4 4 = 2.11 = 2.11 ,D D3 3 = = 负值(以负值(以0 0代表)代表)XRnn1.2541202525= (1)X (1)X 管制图管制图 CL = X =50.16CL = X =50.16 UCL = X+A UCL = X+A2 2R=50.16+(0.58)(4.8)=52.93R=50.16+(0.58)(4.8)=52.93 LCL = X-A LCL = X-A2 2R=50.16-(0.58)(4.8)=47.39R=50.16-(0.58)(4.8)=47.39 (2)R (2)R 管制图管制图 CL = R =4.8CL = R =4.8 UCL = D UCL = D4 4R =(2.11)(4.8)=10.13R =(2.11)(4.8)=10.13 LCL = D LCL = D3 3R =( 0 )(4.8)= 0R =( 0 )(4.8)= 04648505254X管制图-3036912R管制图UCLX(52.93)CLX(50.16)LCLX(47.39)UCLR(10.15)CLR(4.8)LCLR(0)(1)(1)公组样本大小公组样本大小 n n 相等时:相等时:CL = P = CL = P = UCL= P +3 P UCL= P +3 P(1-P1-P)/n/n LCL= P -3 P LCL= P -3 P(1-P1-P)/n/n (2) (2)n n不等,且相差小于不等,且相差小于20%20%时:时: CL = PCL = P UCL= P +3 P UCL= P +3 P(1-P1-P)/n/n LCL= P -3 P LCL= P -3 P(1-P1-P)/n/n (3) (3)n n不等,且相差大于不等,且相差大于20%20%时:时: CL = PCL = P UCL= P +3 P UCL= P +3 P(1-P1-P)/ /nini LCL= P -3 P LCL= P -3 P(1-P1-P)/ /ninidn2 2、实例、实例 某工厂制造外销产品,每某工厂制造外销产品,每2 2小时抽取小时抽取100100件来检查,将检件来检查,将检 查所得之不良品数据,列于下表,利用此项数据,绘制查所得之不良品数据,列于下表,利用此项数据,绘制 不良率(不良率(P P)管制图,控制其品质。管制图,控制其品质。组别ndp组别ndp组别ndp1234567891010010010010010010010010010010034385575560.030.040.030.080.050.050.070.060.050.061112131415161718192010010010010010010010010010010036852362750.030.060.080.050.020.030.060.020.070.052122232425100100100100100584540.050.080.040.050.04合计2500125平均1000.051 1、求管制界限、求管制界限 CL = P = = 0.05 = 5%CL = P = = 0.05 = 5% UCL = P +3 = 11.54% UCL = P +3 = 11.54% LCL = P -3 LCL = P -3 (为负值,视为为负值,视为0 0)1252500P(100 - P)nP(100 - P)n2 2、点绘管制图、点绘管制图 0246810121412345678910 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25UCLCLLCL取样数n平均数管制图标准差管制图全距管制图中位数管制图个别值管制图最大值最小值管制图X 图管制界限中线管制界限中线管制界限管制界限管制界限管制界限界限 系数AA1A2C21/C2B1B2B3B4d21/d2d3D1D2D3D4A3D5D6E2A9m3A2C323456789101112131415161718192021222324252.1211.7321.5001.3421.2251.1341.0611.0000.9490.9050.8660.8320.8020.7750.7500.7280.7070.6880.6710.6550.6400.6260.6120.6003.7602.3941.8801.5961.4101.2771.1751.0941.0280.9730.9250.8340.8480.8160.7880.7620.7380.7170.6970.6790.6620.6470.6320.6191.8801.0230.7290.5770.4830.4190.3730.3370.3080.2850.2660.2490.2350.2230.2120.2030.1940.1870.1800.1730.1670.1620.1570.1530.56420.72360.79790.84070.86860.88820.90270.91390.92270.93000.93590.94100.94530.94900.95230.95510.95760.95990.96150.96380.96550.96700.96840.96961.77251.38201.25331.18941.15121.12591.10781.09421.08371.07531.06841.06271.05791.05371.05011.04701.04421.04181.03961.03761.03581.03421.03271.03130.0000.0000.0000.0000.0260.1050.1670.2190.2620.2990.3310.3590.3840.4060.4270.4450.4610.4770.4910.5040.5160.5270.5380.5481.8431.8581.8081.7561.7111.5721.6381.6091.5841.5611.5411.5231.5071.4921.4781.4651.4541.4431.4331.4241.4151.4071.3991.3920.0000.0000.0000.0000.0300.1180.1850.2390.2840.3210.3540.3820.4060.4280.4480.4660.4820.4970.5100.5230.5340.5150.5550.5653.2672.5682.2662.0891.9701.8821.8151.7611.7161.6791.6451.6181.5941.5721.5521.5341.5181.5031.4901.4771.4661.4551.4451.4351.1281.6932.0592.3262.5342.7042.8472.9703.0783.1733.2583.3363.4073.4723.5323.5883.6403.6893.7353.7783.8193.8583.8953.9310.88650.59070.48570.42890.39460.36980.35120.33670.32490.31520.30690.29980.29350.28800.28310.27870.27470.27110.26770.26470.26180.25920.25670.25440.8530.8880.8800.8640.3480.3330.8200.8080.7970.7870.7780.7700.7620.7550.7490.7430.7380.7330.7290.7240.7200.7160.7120.7090.0000.0000.0000.0000.0000.2050.3870.5460.6870.8120.9241.0261.1211.2071.2851.3591.4261.4901.5481.6061.6591.7101.7591.8043.6854.3584.6984.9185.0785.2055.3075.3945.4695.5345.5925.6465.6935.7375.7795.8175.8545.8885.9225.9505.9796.0066.0316.0580.0000.0000.0000.0000.0000.0760.1360.1840.2230.2560.2840.3080.3290.3480.3640.3790.3920.4040.4140.4250.4340.4430.4520.4593.2672.5752.2822.1152.0041.9241.8641.8161.7771.7441.7161.6921.6711.6521.6361.6211.6081.5961.5861.5751.5661.5671.5481.5412.2241.2650.8290.7120.5620.5200.4410.4190.3690.0000.0000.0000.0000.0000.0780.1390.1870.2273.8652.7452.3752.1792.0551.9671.9011.8501.8092.6651.7721.4571.2901.1841.1091.0541.0100.9752.6951.8261.5221.3631.2631.1911.1431.1041.0721.8801.1870.7960.6910.5490.5090.4320.4120.3630.6030.4630.3870.3410.3080.2820.2620.2460.232正常点子之动态之管制图,如图一。正常点子之动态之管制图,如图一。 1 1、多数的点子,集中在中心线附近,且两边对称。、多数的点子,集中在中心线附近,且两边对称。 2 2、少数的点子,落在管制界限附近。、少数的点子,落在管制界限附近。 3 3、点子之分布呈随机状态,无任何规则可寻。、点子之分布呈随机状态,无任何规则可寻。 4 4、没有点子超出管制界限外(就是有也很少)。、没有点子超出管制界限外(就是有也很少)。不正常点子之动态之管制图不正常点子之动态之管制图 1 1、在中心线附近无点子、在中心线附近无点子 此种型态吾人称之为此种型态吾人称之为“混合型混合型”,因样本中可能,因样本中可能 包括两种群体,其中一种偏大,另一种偏小,包括两种群体,其中一种偏大,另一种偏小, 如图二。如图二。 2 2、在管制界限附近无点子、在管制界限附近无点子 此种型态此种型态吾人称之为吾人称之为“层别型层别型”,因为原群体可,因为原群体可 能已经加以检剔过,如图三。能已经加以检剔过,如图三。 3 3、有点子逸出管制界限之现象、有点子逸出管制界限之现象 此种称之为此种称之为“不稳定型不稳定型”如图四。如图四。UCLCLLCLUCLCLLCLUCLCLLCLUCLCLLCL图一图三图四管制图之不正常型态之鉴别是根据或然率之理论而管制图之不正常型态之鉴别是根据或然率之理论而加以判定的,出现下述之一项者,即为不正常之型加以判定的,出现下述之一项者,即为不正常之型态,应调查可能原因。态,应调查可能原因。检检定规则定规则1 1:3 3点中有点中有2 2点在点在A A区或区或A A区以外者区以外者(口诀:(口诀:3 3分之分之2A2A)检检定规则定规则2 2:5 5点中有点中有4 4点在点在B B区或区或B B区以外者区以外者(口诀:(口诀:5 5分之分之4B4B)UCLCLLCLABCCBAUCLCLLCLABCCBA检检定规则定规则3 3:有有8 8点在中心线之一侧,但点在中心线之一侧,但C C区并无点子者。区并无点子者。( (口诀口诀:9:9单侧单侧) )UCLCL+3+2+1A区B区C区检检定规则定规则4 4:有有8 8点在中心线之两侧点在中心线之两侧, ,但但A A区并无点子者区并无点子者. .( (口诀口诀:8:8缺缺A)A)UCLXLCLABCCBA检检定规则定规则5 5:1 1、连续、连续5 5点继续上升(或下降)点继续上升(或下降)注意以后动态。(如图注意以后动态。(如图26a26a)2 2、连续连续6 6点继续上升(或下降)点继续上升(或下降)开始调查原因。(如图开始调查原因。(如图26b26b)3 3、连续连续7 7点继续上升(或下降)点继续上升(或下降)必有原因,应立即采取措施。(必有原因,应立即采取措施。(26c26c)+3+2 +1 -1 -2 -3 XXXUCLCLLCL图26a图26b图26c管制图上诸点,以中心线(管制图上诸点,以中心线(CLCL)为主,划分两部分,(一)为主,划分两部分,(一在上方,一在下方),若一点或连续数点在管制图中心线在上方,一在下方),若一点或连续数点在管制图中心线之一方,该点或连续数点为一串(之一方,该点或连续数点为一串(runrun),加总中心线上方),加总中心线上方的串数及中心线下方的串数,便可判定此管制图是否呈随的串数及中心线下方的串数,便可判定此管制图是否呈随机性。机性。例如有一管制图如下:例如有一管制图如下:UCLCLLCL单独单独1 1点为一串者点为一串者44串串 3 3点构成一串者点构成一串者11串串 4 4点构成一串者点构成一串者11串串6 6串串在管制中心线下方者:在管制中心线下方者:单独单独1 1点为一串者点为一串者22串串 2 2点构成一串者点构成一串者22串串 3 3点构成一串者点构成一串者11串串 4 4点构成一串者点构成一串者11串串6 6串串计计1111点点计计1313点点则此则此管制图之总串数为管制图之总串数为6+6=126+6=12串串由由S.SwedS.Swed和和C.EisenhartC.Eisenhart所作成的表,所作成的表,r=11r=11,s=13s=13( (管制图中心线上方共管制图中心线上方共1111点,下方共点,下方共1313点,取大者点,取大者为为s s,小者为,小者为r r,令令srsr) ),得界限值在,得界限值在0.0050.005时为时为6 6(表(表p=0.005p=0.005)在)在0.050.05时为时为8(8(表表p=0.05)p=0.05),因为此管,因为此管制图总串数制图总串数1111分别大于分别大于6 6或或8 8,故判定此管制图数之,故判定此管制图数之分配具随机性。分配具随机性。表表p=0.005 p=0.005 当机率当机率p=0.005p=0.005时,成串之最低总数表时,成串之最低总数表r s 678910 11 12 13 14 15 1617 18 19206272383339333410334451134455512344556613345556671444556677715445667778816455667788991745567788899101845667788991010 111945667889910 1010 11 112045677889910 1011 11 1212表表p=0.05 p=0.05 当机率当机率p=0.05p=0.05时,成串之最低总数表时,成串之最低总数表r s 678910 11 12 13 14 15 1617 18 192063744844594556105566611556677125667788135667889914567788991015667889910 10 111666788910 10 11 11 111767789910 10 11 11 1212186788910 10 11 11 12 1213 13196788910 10 11 12 12 1313 14 14206788910 11 11 12 12 1313 14 1415一般在制程管制(一般在制程管制(IPQCIPQC)时,要判断制程是否在管制)时,要判断制程是否在管制状态,可用管制图来显示。而管制状态的程度,如用状态,可用管制图来显示。而管制状态的程度,如用数字,则可以用管制系数数字,则可以用管制系数CfCf来表示。来表示。Cf = n . XR / d2其中X = (Xi X)2 k - 1R = Ri1KK K:管制图之组数:管制图之组数 n n:样本大小:样本大小 k k:组数组数CfCf值值判判 断断0.7Cf1.30.7Cf1.3 在在管制状态管制状态(Under Control)(Under Control)CfCf1.31.3不在管制状态不在管制状态(Out of control)(Out of control)CfCf0.70.7有有X X不同的异质群体混在一起不同的异质群体混在一起( (建议再用层别分析建议再用层别分析) )1 1、少量多样之生产型态,不能管制。、少量多样之生产型态,不能管制。2 2、管制计划不实际,无法落实。、管制计划不实际,无法落实。3 3、使用、使用SPCSPC前未作充分准备。前未作充分准备。 例如:制程及管制特性之确定,决定量测方法,例如:制程及管制特性之确定,决定量测方法, 数据如何收集等。数据如何收集等。4 4、欠缺统计技术。、欠缺统计技术。5 5、统计计算太过繁琐费时。、统计计算太过繁琐费时。6 6、量测数据之有效数字位数未标准化。、量测数据之有效数字位数未标准化。7 7、管理阶层不支持。、管理阶层不支持。1 1、经济性:有效的抽样管制,不用全数检验,不良、经济性:有效的抽样管制,不用全数检验,不良 率,得以控制成本。使制程稳定,能掌率,得以控制成本。使制程稳定,能掌 握品质、成本与交期。握品质、成本与交期。2 2、预警性:制程的异常趋势可即时对策,预防整批、预警性:制程的异常趋势可即时对策,预防整批 不良,以减少浪费。不良,以减少浪费。3 3、分辨特殊原因:作为局部问题对策或管理阶层系、分辨特殊原因:作为局部问题对策或管理阶层系 统改进之参考。统改进之参考。4 4、善用机器设备:估计机器能力,可妥善安排适当、善用机器设备:估计机器能力,可妥善安排适当 机器生产适当零件。机器生产适当零件。5 5、改善的评估:制程能力可作为改善前后比较之指、改善的评估:制程能力可作为改善前后比较之指 标。标。CaCpABCD| Ca | 12.5% (1/8)12.5%| Ca | 25% (1/4)25%| Ca | 50% (1/2)50%| Ca |1.33 Cp ( T=8)1.00 Cp 1.33 ( T=6)0.83 Cp 1.00 ( T=5) Cp 0.83P%CpkABCDP0.44%0.44%P 1.22%1.22%P 6.68%6.68%P1.33 Cpk ( 同 C p )1.00 Cpk 1.33 Cpk 1.01 1、CPCP(精密度)(精密度) CP = T/6CP = T/6(双边规格)(双边规格) CP = Su X/3 CP = Su X/3 或或 X SX SL L/3 /3 (单边规格)(单边规格)2 2、CaCa(准确度)(准确度) Ca = X - Sc/(T/2)Ca = X - Sc/(T/2)3 3、CpkCpk(制程能力)(制程能力) CpkCpk = = (1 - |Ca|1 - |Ca|)CpCp4 4、不良率、不良率 PP(综合评价)(综合评价)(1 1)ZuZu = 3 Cp = 3 Cp(1 + Ca1 + Ca)超出下限)超出下限P PU U% % Z ZL L = 3 Cp = 3 Cp(1 - Ca1 - Ca)超出上限)超出上限P PL L% % P% = P P% = PU U% + P% + PL L% % 总不良率总不良率5 5、定义、定义 (1 1)X X :制程平均值:制程平均值 (2 2):制程标准差:制程标准差 (3 3)T T :公:公 差差 (4 4)ScSc:规格中心:规格中心1 1、何谓六个、何谓六个制程?制程? 制程精密度(制程精密度(Cp)= 2.0制程能力指数(制程能力指数(Cpk)1.52、以六个、以六个订为订为品质缺点的基准理由品质缺点的基准理由。在无制程变异情况下(在无制程变异情况下(Cp=Cp=CpkCpk=2=2),产生之缺点率),产生之缺点率仅为仅为0.002ppm0.002ppm。在制程无法消除变异情况下,在制程无法消除变异情况下,Cp=2Cp=2,CpkCpk=1.5=1.5缺点率缺点率为为3.4ppm3.4ppm。-6 -5 -4 -3 -2 -1X+1 +2 +3 +4 +5 +6规格下限规格下限常态分配常态分配(规格中心不偏移)(规格中心不偏移)规格上限规格上限K百分比百分比(%)百万分缺点数百万分缺点数11223344556668.2668.2695.4595.4599.7399.7399.993799.993799.99994399.99994399.999999899.999999831740031740045500455002700270063630.570.570.0020.002规格下限规格下限L5 L5常态分配常态分配规格中心值往左、右移动规格中心值往左、右移动L5规格上限规格上限-6 -5 -4 -3 -2 -1X+1 +2 +3 +4 +5 +6K百分比百分比(%)百万分缺点数百万分缺点数11223344556630.2330.2369.1369.1393.3293.3299.379099.379099.9767099.9767099.99966099.9996606977006977003087003087006681066810621062102332333.43.4制程制程能力指数能力指数 Cp Cp 与制程不良率与制程不良率 P P(ppmppm)对照表(平)对照表(平均值不偏移)均值不偏移)LSL USL 规格界限宽度规格界限宽度KCp不良率ppmKCp不良率ppm0.000.170.330.500.670.831.001.171.331.501.671.832.002.172.332.502.672.833.000.000.060.110.170.220.280.330.390.440.500.560.610.670.720.780.830.890.941.001000000.000867632.335738882.680617075.077504985.075404656.762317310.508243345.009182422.439133614.40395580.70566753.01545500.26430260.28019630.65812419.3317660.7614606.5322699.7963.333.503.663.834.004.164.334.504.664.835.005.165.335.505.665.836.006.166.331.111.171.221.281.331.391.441.501.551.611.671.721.781.831.891.942.002.052.11868.460471.110248.954128.14364.24131.36314.9116.9033.1111.3650.5830.2430.0980.0390.0150.0060.0020.0010.000标准差标准差与与ppmppm制品质水准对照表制品质水准对照表(规格中心往左、右移动(规格中心往左、右移动1.51.5)标准差ppm标准差ppm标准差ppm标准差ppm标准差ppm标准差ppm标准差ppm1.001.101.201.301.401.501.601.701.801.902.002.102.202.302.402.502.602.702.802.903.003.103.20697.700655.400617.900579,300539,800500,000460,200420,700382,100344,600308,733274,300242,000211,900184,100158,700135,700115,10096,80080,76066,80354,80044,5703.303.403.503.603.703.803.853.903.913.923.933.943.953.963.973.983.994.004.014.024.034.044.0535,93028,72022,75017,86013,90010,7209,3878,1987,9767,7607,5497,3447,1436,9476,7566,5696,3876,2006,0365,8685,7035,5435,3864.064.074.084.094.104.114.124.134.144.154.164.174.184.194.204.214.224.234.244.254.264.274.285,2345,0854,9404,7994,6614,5274,3964,2694,1454,0243,9073,7923,6813,5723,4673,3643,2643,1673,0722,9802,8902,8032,7184.294.304.314.324.334.344.354.364.374.384.394.404.414.424.434.444.454.464.474.484.494.504.512,6352,5552,4772,4012,3272,2562,1862,1182,0521,9881,9271,8661,8071,7501,6951,6411,5891,5381,4891,4411,3951,3501,3064.524.534.544.554.564.574.584.594.604.614.624.634.644.654.664.674.684.694.704.714.724.734.741,2641,2231,1831,1441,1071,0701,0351,0019689359048748488167897627367116876646416195984.754.764.774.784.794.804.814.824.834.844.854.864.874.884.894.904.914.924.934.944.954.964.975775575385195014844674504344194043903763633503373253133022912802702604.984.995.005.015.025.035.045.055.065.075.085.095.105.205.305.405.505.605.705.805.906.00251242233224216208200193186179172166159108724831.820.813.48.64.83.4