七颗钻石流程（PPT 38页）

1、17 Diamond Process七颗钻石流程Developed by: GMTG-ArlingtonL. ONeal / C. Kessler Aug 2000Revised: 8 Aug 20002What is the 7 Diamond Process?七颗钻石的流程是什么？The 7 Diamond Process is one of many tools that can be used in the problem solving process.七颗钻石流程是可以用来解决质量问题的工具之一。This tool is used to investigate discrepanc

2、ies discovered by the following: 它可以用来调查以下方面发现的差异 Global Customer Audit System (GCAS) 全球顾客评审 Yard Walk Audits 生产线上巡检 Verification Stations 检验工位3 Purpose of the 7 Diamond Process 7颗钻石流程的目的 The 7 Diamond Process is a structured way of assessing our manufacturing process to determine whether of not it

3、has failed to meet the quality standard demanded by our customers.7颗钻石流程是一个构建好的评价我们的制造流程是否满足了顾客所要求的质量标准的一个方法47 Diamond Process 流程Responsibility责任责任Production第一步第一步 1Production第二步第二步2Production第三步第三步3Rel. Engineer/SQA/Supplier负责的负责的SQDE工程工程师师/供应商供应商 4CorrectProcess?正确的工艺CorrectTool?正确的工具正确的工具CorrectP

4、art?正确的零件正确的零件Parts Quality?零件质量零件质量Responsibility责任责任Process ControlManagers工艺控制负责人工艺控制负责人5aIs Engineering support required?是否需要工程方面的支持是否需要工程方面的支持Problem IdentifiedBegin Interrogation问题定义问题定义(开始调查开始调查)Responsibility责任责任QET PST (Lead)5bSMTRGM (Lead)6Statistical Engineering(Red X Strategies)统计工程统计工程(

5、红红-X方法方法)7Will Process ChangeResolve?工艺更改能解决问题吗工艺更改能解决问题吗Product ChangeRequired?产品更改需要吗？产品更改需要吗？Hardy Perennial or Extremely ComplexProblem非常复杂的问题非常复杂的问题SQA - Supplier Quality AssuranceQET - Quality Engineering TeamPST - Plant Support TeamSMT- Systems Management TeamRGM - Reliability Growth Manageme

6、nt5Review of Responsibility职责回顾 Diamonds 1-4Production & Reliability钻石1-4 生产&可靠性 Filter 5aProcess Control Manager (PCM)5a 过滤 工艺控制负责人 Diamond 5b-7Product Engineering钻石5b-7 产品工程6Insert Sample CountermeasureCard Here此处插入对策卡样卡77 Diamond Process Stages流程的各步骤Stages 1 & 2 of the process are use

7、d to determine if the Production organization is running the assembly process to design intent. 1 1、2 2步是用来确定生产部门运行的装配流程满足设计内容。步是用来确定生产部门运行的装配流程满足设计内容。 The initial investigation (Stage 1) is done where the defect was identified.最初的调查最初的调查(第一步第一步)应在发现缺陷的地方开始应在发现缺陷的地方开始Stage 2 is only used when the in

8、vestigation in Stage 1 determined that the cause of the problem was from an upstream source. 第第2步只能当第一步的调查步只能当第一步的调查,确定问题是来源其他方面时确定问题是来源其他方面时,才可开始才可开始If the process isnt being managed to design intent, then it must be corrected and validated, prior to asking for Engineering assistance.如果工艺没有满足设计内容，当

9、需要工程方面的协助前，必须进行纠正并要有效。如果工艺没有满足设计内容，当需要工程方面的协助前，必须进行纠正并要有效。Engineering referral (Stage 3) occurs when the manufacturing process does meet design intent and the problem still exists.当制造过程满足设计内容并且问题依然存在时，第当制造过程满足设计内容并且问题依然存在时，第3步开始。步开始。81 - Correct Process正确的过程 Are the correct Best People Practice shee

10、ts posted?是否有正确的操作指导文件？ Are the Best People Practices being followed?是否执行操作文件？ Is the operators Key Point Chart being followed?是否满足关键操作点控制图 Are the correct documents posted on the operation certification board? 是否在操作示板上有正确的文件 Is the job being performed to the PADs?是否按照PAD操作 Can any of these cause th

11、e problem?以下的问题有可能产生问题吗？以下的问题有可能产生问题吗？Stages 1&2ProductionCorrects正确的生产正确的生产Production2Production3Rel. Engineer/SQA/Supplier 4CorrectProcess?正确的工艺过程正确的工艺过程CorrectTool?正确的工具正确的工具CorrectPart?正确的零件正确的零件Parts Quality?零件的质量零件的质量81 - Correct Process正确的过程 Has a mandatory sequence been identified? Is it

12、 being followed? 是否强制的操作序列号已识别，是否执行了 Is the job being done the same on both shifts?在各班次中操作工作是否一致 Does the operator understand what the product standards are?操作者是否理解产品标准 Is it the regular operator? Has there been a lot of turnover on the job? 是否为固定操作工？是否此操作有很多轮换人员 Has the operator been properly train

13、ed?操作者是否正确培训过 Are the visual aids current? 目前是否有目视化的辅助措施 Does the operator understand the quality outcomes of her/his job?操作者是否知道他/她的岗位的产品的输出质量 Does the operator know how to communicate when he/she has a problem?操作者是否知道当他/她的岗位出现质量问题时如何传递沟通信息？Can any of these cause the problem?以下的问题有可能产生问题吗？以下的问题有可能产

14、生问题吗？Stages 1&2ProductionCorrects正确的生产正确的生产Production2Production3Rel. Engineer/SQA/Supplier 4CorrectProcess?正确的工艺过程正确的工艺过程CorrectTool?正确的工具正确的工具CorrectPart?正确的零件正确的零件Parts Quality?零件质量零件质量9 Are the correct tools & fixtures being used? (both shifts) 是否使用正确的工具/夹具(各班次) Are the tools set to the

15、specified torque? 工具是否设置成规定的扭矩 Are they properly calibrated?是否进行适当的校准 Are both shifts using the same tool? 是否各班次用同样的工具 Are the bits or sockets worn?是否螺丝刀或套筒已磨损 Has an extra air hose been attached to the tool? 是否在工具上有多余的空气管 Is the tool tied to the Andon system?工具是否与暗灯相连 Has the tool been put on Bypas

16、s?是否工具被旁路 Do the tools & fixtures have mutilation protection?是否工具/夹具有损毁保护 Has the workstation been error proofed? 工位是否有防错设施 Does the workstation layout allow the operator to work effectively? 是否工位的布置适合操作者有效的工作 Has the Preventive Maintenance been done? (check log) 是否进行了预防性维修(检查表) Are tools functi

17、oning correctly? 工具功能是否正确Stages 1&2ProductionCorrectsProduction1Production3Rel. Engineer/SQA/Supplier 4CorrectProcess?正确的工艺过程正确的工艺过程CorrectTool?正确的工具正确的工具CorrectPart?正确的零件正确的零件Parts Quality?零件质量零件质量2 - Correct Tool正确的工具Can any of these cause the problem?10 Is the Parts Routing current?零件的路径是否正确

18、Are the correct part numbers identified on the material racks?是否在料架上标识有正确的零件号 Are parts stocked in correct location on the rack?在料架上摆放位置是否正确 Do the part numbers on the boxes agree with the rack?包装盒上零件号与料架上是否一致 Are all pull cards available?拉动卡是否有效 Has a PAA been issued changing part usage?是否有零件用途改变的P

19、AA Has the PAA expired?PAA是否过期 Is error proofing needed?是否需要防错措施 Is existing error proofing device working correctly? 是否已有的防错设备运行正确Stages 1&2Production1Rel. Engineer/SQA/Supplier 4CorrectProcess?正确的工艺过程正确的工艺过程ProductionCorrectsCorrectPart?正确的零件正确的零件Production2CorrectTool?正确的工具正确的工具Parts Quality?

20、零件质量零件质量3 - Correct Part正确的零件Can any of these cause the problem?11The Reliability Engineer is responsible for determining if parts have changed and overall part quality. If parts quality (out of specification) is determined to be the problems root cause, then the RE will: write PR&Rs to notify t

21、he supplier that there is a problem.可靠性工程师确定零件是否更改过并对产品全部质量负责。如果由于零件质量(超差)是根本原因，那么应：填写PR&R通知供应商： work with Supplier Quality to validate the corrections.同供应商共同确认纠正措施set up sorting operations and production will support sorting of material at the operation.采取筛选措施，制造应支持在工位上的物料筛选 work with Group Lea

22、ders to validate countermeasures or containment.同工段长共同确认对策和遏制措施If part variation within specification is the root cause, then the RE will:如果确认零件在规范内，那么RE应：work with the supplier and SQA to move the part back to the needed range within the specification同供应商共同工作，SQA将零件返回到规范内需要的范围work with Quality Engi

23、neering to determine if an Engineering Change is required to provide irreversible corrective action同质量工程师合作，确定是否需要工程更改这种不能消除的纠正措施Stages 1&2Production1CorrectProcess?正确的工艺流程正确的工艺流程Rel. Engineer/SQA/SupplierPartsQuality?零件质量零件质量Production2CorrectTool?正确的工具正确的工具CorrectPart?正确的零件正确的零件Production34 -

24、Part Quality零件质量12Diamonds 1-4 in Review钻石1-4步回顾Diamonds 1-4 are for evaluating the stability of the process. 1-4步用来评价工艺过程的稳定性Once a problem has been identified, the automatic response must be to immediately step thru diamonds 1-4.当问题被定义后，1-4步的负责人员就自动确定下来It must become inherent in our problem solvin

25、g thought process.这些步骤是问题解决过程中固定的流程Responsibility职责职责Process ControlManagers过程控制负责人过程控制负责人5aIs Engineering support required?是否需要工程的支持是否需要工程的支持135a - Engineering Filter 5a-工程过滤Is Engineering support required? 需要工程方面的支持吗5a is a step to filter out and resolve less-complex issues before seeking help fro

26、m Quality Engineering.5a是一步过滤出并将不复杂的问题在寻求质量工程帮助前解决The Process Control Manager is responsible for conducting initial studies prior to escalating the issue.过程控制负责人负责在提升问题前指导初始研究These studies may include but are not limited to:这些研究应包括但不局限在:Problem Definition Tree 问题定义树 5 Whys 5个为什么 Statistical Process

27、Control 统计过程控制 Design of Experiment (DOE) 试验设计Shainin Techniques (quick & dirty) 技术(快速& 脏) If after the initial studies the cause of variation has not been determined, the issue is referred to Product Engineering. The problem definition tree is the minimum exit criteria to go from Diamond 5a

28、 to 5b. 如果经过初始研究，变差的产生原因还没有确定，就需要产品工程的支持。问题定义树是从5a-5b的基本方法。QualityEngineering质量工程5aProblem Solving Toolbox 问题解决工问题解决工具箱具箱Project title: Poor adjustment of RR door panel 805-830Leader: Pedro Aranda AlfaroSponsor:Juan Carlos LiceaArea: VAETCoach: Leonardo Chvez salcedoInitial date: oct-04-2002Final da

29、te: oct-29-2002Problem description:This month it was reported by the shipping lot in USA a problem of quality existed in the 805/830 vehicles. The problem is the poor adjustment in RR door panel.Projects statement:Find and improve the Red X that produce the poor adjustment in the RR door panel for t

30、he model 805/830 in Silao Assembly plant.Strategy:We initiated this project using the model to model strategy, because there was a good contrast and good leverage based on multi-vari see pag 6.Measurement system:As measurement system a Force gage was used.This measurement system passed the isoplot w

31、ith DR=13.6, DM=1.0 lbs, and DP=13.6 lbs (see page 4)Clue generation:Stage 1 shows that the Red X doesnt live in the process. The stage 2 shows that the Red X lives in the door panel. The pair comparison shows that the door molding is the part with the best contrast.Statistical confirmation:Once we

32、detected the Red X candidate, I decided to do a B vs C six pack trial, in order to confirm the door molding is the influence to make the customer satisfaction. The six pack passed with 95% of confidence and end count of 6.Irreversible corrective action:To modified the flange 1.5 mm in length to keep

33、 a better position and avoid that the door panel take out of position.Improvements:Reduce warranty cost to repair the door panel caused by poor fit (loose) and eliminate the condition in 100% in vehicles 805/830 models. The amount of money from jul 01 to jul 02 was 11,084.77 USD.Lessons learned:We l

34、earned that is necessary looking other alternatives using other strategy when is not possible invest money but always focus to guarantee the customer enthusiasm, therefore this project is an example of this.Executive Summary 执行总结项目题目项目题目：右后门板调整不好(805/830车型)。领导领导； Pedro Adranda Alfaro发起人发起人： Juan Car

35、los Licea区域区域： VAET教练教练： Leonardo Chavez salcedo起使日起使日： 2002年10月4日截止日截止日：2002年10月29日问题描述问题描述： 本月收到报告，在美国有关于门饰板的质量问题，右后门饰板调整不好。(805/830型)项目综述项目综述： 针对Lilao装配厂805/830车型的右后门饰板，发现并解决其配合不好的问题。策略策略： 我们起初应用车型对车型策略，因为多车之间有很好的对比度和平衡关系。(见见第6页)测量系统测量系统：用测力计作为测量系统。这种测量系统通过等量图。 (DR=13.6, M=1.0lbs, P=13.6lbs见第4页 线

36、索产生线索产生： 阶段1表明红X不在过程中。阶段2表明红X产生在门饰板处。成对比较表明门型是成对比较点。统计确认统计确认：一旦我们查到了候选的红X，我们决定做B vs C六组数据比较，这是为了确认门型影响客户满意度。用6对数据进行比较具有95%的可信度和最大累加值为6.不可撤销的纠正措施不可撤销的纠正措施：为使门边缘加长1.5mm以保证正确的位置不偏离。改进措施改进措施：减少保修费用来修复由于配合不好产生的门饰板问题，并且100%消除803/805车型的缺陷。学到的经验学到的经验： 我们学到了 当投资不会太多的情况下，用其它策略以寻求可选择的方法解决问题。但始终要关注顾客热忱。此项目便是一个这

37、样的例子。Project Definition Tree/项目定义树项目定义树G e o m e tric/几 何 特 性R H /右 侧5 0 %F in d a n d e lim in a te th e R e d X th a t ca u se sp o o r a d ju stm e n t in th e R R d o o r p a n e l a t8 0 5 /8 3 0 m o d e ls/发 现 和 消 除 8 0 5 /8 3 0 车 型上 出 现 的 引 起 后 侧 门 饰 板 调 整 困 难 的 红 XB o th H /两 侧L H /左 侧5 0 %R

38、 e a r d o o r/后 门1 0 0 %F ro n t d o o r/前 门0 %B o th /都 有E ffo rt to re le a se th e d o o r p a n e l(lb s)车 门 饰 板 拆 卸 力 (磅 )O th e r/其 它E v e n t/事 件D e fe ct/缺 陷P h y sic/物 理 特 性D o o r p a n e l lo o se /车 门 饰 板 松 动8 0 5 /8 3 0 m o d e ls车 型Problem characterization问题描述Warranty condition/保修条件Th

39、e problem is presented only in the rear door问题只是在后侧车门出现BASEDBASED: DISTRIBUTON LOT CAMPAINGCURRENTCURRENT: 100 % door panel 805830 models loose目前状态：805/830型车门饰板100%松动。GOALGOAL: eliminate 100% the poor fit.目标：100%消除不良的配合Project statement项目综述Need energy to release the trim door panel需要用力才能卸下门饰板Custome

40、r is calling the problem in both sides客户现在对两侧都在抱怨Effort to release (lbs)/Effort to release (lbs)/释放力释放力( (磅磅) )Frequency频率频率051015202530354006121824303642CURRENT现有现有DESIRED希望希望DM=1.19 lbs/磅Prosess过程Rest of vehicle车辆其它部分Modified the flange 1.5 mm in length将法兰在长度上修改1.5厘米The Red X is the door moding th

41、atis being installed in the trim panel红X是被安装在车门饰板内的车门饰板饰件Molding door panel车门饰板饰件Rest of door车门其它部分Trim door panel车门饰板Parts零件Model 车型to 对Model 车型Other strategy其它策略DP= 29 lbs磅Solution tree项目解决树项目解决树TARGET: Eliminate condition 100%目标：目标： 100%100%消除现有问题消除现有问题PASSED ISOPLOT DR=15.2 SEE PAG 4通过等量图验证 DR=1

42、5.2 参见第4页PASSED STAGE 1 SO THE RED X DOESNT LIVE IN THE PROCESS SEE PAG # 7.通 过 第 一 阶 段 验 证 ， 因 此 红 X 不 在 装 配 过 程 中 ， 参 见 第 7 页 。THE COMPONENT SEARCH STAGE 2 SHOWS THAT THE RED X DOES NOT LIVE IN THE TRIM DOOR PANEL SO LIVES IN THE REST OF THE DOOR PANEL. SEE PAG # 7./零部件分析阶段2显示红X不是由车门内饰板造成的,所以应是由车门

43、板的其余部分引起的,见7页.PAIR COMPARISON SHOWS THAT THE DOOR PANEL MOLDING HAS THE CHARACTERISTIC THAT PRODUCE THE DIFFERENCE SEE PAG 9/ 配对对比显示车门饰板饰件有造成差异的特征，参见第9页THIS IS THE BEST STRATEGY BASED ON MULTIVARI SEE PAG 5.这是基于多重变换比较得出的最佳策略，参见第5页。PASSED B vs C WHERE IT SHOWS THAT THE DOOR MOLDING KEEP IN POSITION T

44、HE DOOR PANEL SEE PAG 10, BUT WE CHOICE OTHER CHARACTERISTIC THAT KEEP IN POSITION THE DOOR PANEL AND WITOUT INVEST MONEY SEE PAG 11 & 13.通过BC对比试验，显示车门饰板饰件能够使车门饰板保持正确位置，见第10页。但是我们选择能够保证车门饰板位置并且不用增加投资的其它特性，参见第11和13页。Frequency频率频率GREEN Y RUN CHART SEE PAG 17/绿Y字流程图参见第17页。05101520253035400612182430

45、3642DESIRED希望希望CURRENT现有现有BASED: DISTRIBUTON LOT CAMPAINGEffort to release (lbs)Effort to release (lbs)释放力释放力( (磅磅) )D DM = 1.0 lbsD DP = 13.6 lbsDR = 13.6Passed Isoplot IsoplotA Force gage was usedas the measurement system拉力计作为测量工具拉力计作为测量工具通过ISOPLOT评估POINT TOPOINTThere are no contrast in this strat

46、egy there are no difference.There is a good contrast but the leverage is not enough because we dont have tools to measure it.This strategy provide good contrast and the best leverage based on multi-vari chart see pag 6There are no contrast through the timeStrategy diagram PLANT TOPLANTMODEL TOMODELT

47、RUCK TOTRUCKSIDE TOSIDESAME PANELSAME PLANTSAME MODELSAME TRUCKThere is a contrast between truck to truck and good leverage but the contrast is not enough based on multi-vari see page 6.EVENT TOEVENTSAME POINTThere are no contrast in this strategy there are no difference event to event.策略图事件对事件同一个点点

48、对点同一块扳同一侧对同一侧同一台车车对车同一型号型号对型号同一个工厂工厂对工厂在这个对比中,无差异.在这个对比中,无差异.在这个对比中,有差异.但无测量工具.在车与车的对比中,有差异.但不能满足MULTI-VARI的要求.在这个对比中,有差异.且能满足MULTI-VARI的要求.在这个对比中,无差异.510152025303540455014710131619222528313437404346495255586164677073767982858891Multi - variNOTE: This graphic shows that the best contrast is model to

49、 model.SideTruck1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31EFFORT TO TAKE OFF (lbs)R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R L R LCustomer satisfaction limitBOBWOWModelC C C C A A A A

50、A A A A A A A S S S S S S S S S S S S S S S SNOTE: S: SUBURBAN 830 MODEL A: AVALANCHE 805 MODEL C: CADILLAC 806 MODEL注:SAC三种车型最好最坏顾客的满意底线注:此图显示出在型号与型号的对比中有最大的差异.松脱力(磅)Component searchNOTE: This graphic shows that the Red X suspect does not live in the process because it passed the stage #1. The stag

51、e 2 shows that the Red X suspect does not live in the seal window. So the Red X suspect lives in the molding door panel.48.416.27.54746.348.246.647.58.58.30102030405060OriginalR1 & R1 (Door Panel)R2 & R2 (Door Panel)R3 & R3 (Door Panel)Seal WindowDoor PanelMolding doo

52、r panelHomeEffort (lbs)BOBWOWSTAGE 1STAGE 2第一阶段第二阶段最好最坏原状态第一次拆装第二次拆装第三次拆装门窗密封条门饰板门饰板饰条铰链注:这个图显示因为通过了第一阶段的试验,所以RED X不是由操作造成.第二阶段的试验显示门窗密封条不是RED X,门饰板饰条是RED X要素查找规则规则Rule 1.Rule 1.There are complete separation between the BOB and There are complete separation between the BOB and WOW values.WOW values.

53、将最好和最坏的值完全分开将最好和最坏的值完全分开规则规则Rule 2. Rule 2. DYV1RDYV1R设设Where: Where: R= R= R RBOB BOB + R + RWOWWOW 2 2那么那么thenthenR RBOBBOB=1.9=1.9R RWOWWOW=1.2=1.2R= R= 1.9 + 1.2 1.9 + 1.2 = = 3.13.1 = 1.55. = 1.55. 2 2 2 2DY = YDY = YBOBBOB - Y - YWOWWOW = 46.8 - 8.1 = 38.7 = 46.8 - 8.1 = 38.7 如果如果ififDY V1RDY

54、V1R那么那么thenthen 38.7 (0.89) (1.55)38.7 (0.89) (1.55)所以所以soso 38.7 1.38 38.7 1.38 所以满足规则所以满足规则1 1和规则和规则2 2的要求的要求so passed Rule 1 and Rule 2通过问题为每个单元设定判定极限通过问题为每个单元设定判定极限Set decision limits for each unit by using the questions:Set decision limits for each unit by using the questions:DLDLBOBBOB= Y= YBO

55、BBOB + V2R + V2RDLDLWOWWOW= Y= YWOWWOW + V2R + V2R那么那么Then Then udludl = 48.83 = 48.83 DL DLBOBBOB = 46.8 + 1.31 (1.55) = = 46.8 + 1.31 (1.55) = ldlldl = 44.77 = 44.77 udludl = 10.13 = 10.13 DL DLWOWWOW = 8.1 + 1.31 (1.55) = = 8.1 + 1.31 (1.55) = ldlldl = 6.07 = 6.07 结果结果ResultsCARACTERISTICABOB(144

56、794)WOW(145644)BOB(145190)WOW(145687)BOB(144542)WOW(145688)BOB(144721)WOW(144934)BOB(144614)WOW(144966)Gree Y34.59.746.343.49.730.512.1门饰件门饰件Door moldingYESNOYESNOYESNOYESNOYESNOPaired Comparison备注备注NOTE: We consider that the door panel molding is the Red X candidate in the pair NOTE: We

57、consider that the door panel molding is the Red X candidate in the pair comparison because is the only difference between panel to panel. In 805/830 comparison because is the only difference between panel to panel. In 805/830 vsvs 806 806 models.models.我们认为门板装饰件是可能的我们认为门板装饰件是可能的Red X, Red X, 因为在车型因为

58、在车型805/830805/830 和和 车型车型806806对比后只有门板有差对比后只有门板有差异。异。WOWWOWBOBBOBDOOR MOLDINGRED X CANDIDATEPassed B Passed B vsvs C with 95% of confidence that the molding door panel is C with 95% of confidence that the molding door panel is the Red X with complete separation and end count of 6.the Red X with comp

59、lete separation and end count of 6.在在 完全分离，完全分离，End End count count 为为5 5的情况下，的情况下， 以以95%95%的置信度通过的置信度通过B v S B v S 表明门板装饰件是表明门板装饰件是Red XRed XB vs C Six packB = 有门饰件的有门饰件的车车Vehicles with door molding.C = 没有饰件的车没有饰件的车Vehicles without door molding. Req: 置信置信度度confidence = 95%次序次序OrderGreen Y (lbs)B25.

60、9yesB50yesC8.6noB28.6yesC16.3noB25.9yesB50yesC16.3noC13.3noC13.3noB28.6yesC8.6noRed X 门饰件门饰件doormoldingRed X 门饰件门饰件doormolding试验试验Test排序排序Ranked orderGreen Y (lbs)Once confirmed that the RED X is living in the door panel molding, we decided to change our Once confirmed that the RED X is living in the door panel molding, we decided to change our strategy from “mod