spc統(tǒng)計(jì)運(yùn)用及品管實(shí)務(wù)工具(參考版)
2025-02-22 06:40本頁(yè)面
【正文】 3) 記住 : 控制限值與顧客規(guī)定限值無(wú)關(guān) 控制上限 中線 樣本均值 68 常用 控制圖類型 (XS) SXLotLotMon i torproc e s sm e a nMon i torproc e s ss ta nd a r ddevi a ti on69 常用 控制圖類型 (XR) RXLotLotMon ito rproc essm eanMon ito rDev iati on70 短期 N 30 For control charts with N 30 lots, rather than the usual UCL (upper control limit) and LCL (lower control limit), there are dual sets of control limits: ? Outer Control Limits(3s). ? Inner Control Limits (1s). Lot N um be rU C L ( o u t e r )U C L ( i n n e r )L C L ( i n n e r )L C L ( o u t e r )C e n t e r l i n eProcessPerformance“ U n c e rt a i nt y Zo ne s ” U s u a l C ont ro l L i m i t s71 Lot Nu mb erU C L (o u te r )U C L (i n n e r )L C L (i n n e r )L C L (o u te r )C e n te r l i n eProcessPerformanceLot Nu mb erU C L (o u te r )U C L (i n n e r )L C L (i n n e r )L C L (o u te r )C e n te r l i n eProcessPerformanceLot Nu mb erU C L (o u te r )U C L (i n n e r )L C L (i n n e r )L C L (o u te r )C e n te r l i n eProcessPerformance短期 N 30 Any point outside either of the outer control limits indicates an unstable process. All points falling between both inner control limits indicates a stable process. If any points fall inside either “uncertainty zone” (but none are outside the outer control limits), we cannot say whether or not the process is stable, because we do not yet have enough lots to be sure at this time. 72 Lot Nu mb erU C L (o u te r )U C L (i n n e r )L C L (i n n e r )L C L (o u te r )C e n te r l i n eProcessPerformanceLot Nu mb erU C L (o u te r )U C L (i n n e r )L C L (i n n e r )L C L (o u te r )C e n te r l i n eProcessPerformanceLot Nu mb erUCLL C LC e n te r l i n eProcessPerformanceWith few lots, the control chart has wide uncertainty zones. It is possible to determine process stability, but in most cases more lots will be required. With more lots, the control chart has narrow uncertainty zones. It is easier to determine process stability, but it is still possible that more lots will be required. Once there are N ? 30 lots, the usual control limits are used (., there are no uncertainty zones). There is full ability to determine process stability. 73 控制圖 代表的含義 A single point on the chart is outside either control limit. This test detects very large, sudden shifts in the process mean or standard deviation. 9 or more consecutive points are on the same side of the centerline. This test detects small shifts or trends in the process mean or standard deviation. 6 (or more) consecutive points are increasing (or decreasing) steadily, without a change in direction. This test detects strong trends in the process mean or standard deviation 74 14 (or more) consecutive points are alternating up and down. This test detects systematic effects, such as alternating machines, operators, suppliers, etc. 4 (or 5) out of 5 consecutive points on the chart are more than 1 standard deviation away from the centerline, on the same side. This test detects moderatesized changes in the process mean or standard deviation. 2 (or 3) out of 3 consecutive points on the chart are more than 2 standard deviations away from the centerline, on the same side. This test detects large changes in the process mean or standard deviation. 75 15 (or more) consecutive points are all within 1 standard deviation of the centerline. This test detects a decrease in process variation. 8 (or more) consecutive points are on both sides of the centerline, but none are within 1 standard deviation of it. This test detects an increase in process variation. ~ End ~ 76 謝謝觀看 /歡迎下載 BY FAITH I MEAN A VISION OF GOOD ONE CHERISHES AND THE ENTHUSIASM THAT PUSHES ONE TO SEEK ITS FULFILLMENT REGARDLESS OF OBSTACLES. BY FAITH I BY FAITH 。 3σ限值爲(wèi)基礎(chǔ) 。我們採(cǎi)用措施修正控制圖表中非隨機(jī)型式，這是成功使用 SPC的關(guān)鍵 。 63 什麼是 統(tǒng)計(jì) 製程 控制 （續(xù)） 基本統(tǒng)計(jì)原理，控制圖表能夠用於識(shí)別過(guò)程變數(shù)中的非固有（非隨機(jī)）型式。控制圖表中包括反映過(guò)程隨機(jī)變動(dòng)固有限值的上下 控制限值 。這些失控信號(hào)無(wú)法說(shuō)明過(guò)程失控的原因，只能表明過(guò)程處?kù)妒Э貭顟B(tài) 。 62 什麼是 統(tǒng)計(jì) 製程 控制 （ SPC） 所有過(guò)程都有固有變動(dòng)（由於一般原因）和非固有變動(dòng)（由於特殊原因）， 我們使用 SPC來(lái)監(jiān)測(cè)並改善過(guò)程 。 第一步是使用統(tǒng)計(jì)方法控制公司的輸出。該工具可用於任何領(lǐng)域：製造業(yè)、商業(yè)，銷(xiāo)售業(yè)等等 … SPC是統(tǒng)計(jì)程式控制 （ Statistical Process Control） 的縮寫(xiě)。 56 管制上限 管制下限 不合格 , 予以篩除 瞭解以上基本觀念後便開(kāi)始加入管制的觀念 。 :製程中只有共同原因的變異 此種現(xiàn)象是穩(wěn)定的 ” 不良 ” 。 通常變化不外下面三種基本狀況的組合 : 整體製程數(shù)據(jù)漂移 散佈變寬 中心值漂移 若將每日之統(tǒng)計(jì)分佈串起來(lái)一起看 ,則又可看到更多變異現(xiàn)象 ,一般可分為兩種如下 : 時(shí)間 時(shí)間 :製程中有特殊或突發(fā)原因而產(chǎn)生變異 , 造成不穩(wěn)定 。 裂紋 Pareto圖 白班 晚班 夜班 周末班 刮傷 剝落 其他 污點(diǎn) 15 10 5 0 15 10 5 0 15 10 5 0 15 10 5 0 裂紋 Pareto圖 40 30 20 10 0 100 80 60 40 20 0 缺陷 計(jì)數(shù) 15 13 6 6 百分比 累積百分比％ 品質(zhì)統(tǒng)計(jì)圖表 柏拉圖 (Pareto Diagrams) 44 品質(zhì)
職業(yè)教育相關(guān)推薦
鄂ICP備17016276號(hào)-1