Design For Manufacturing. Design Documents. Gage R&R DFM

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3 Purpose of the Abloy Part Approval Process is: 1. To provide the evidence that all customer engineering designs and required specifications are properly understood and fulfilled by manufacturing.. To demonstrate that the manufacturing process has the potential to produce the product, consistently fulfilling all requirements during an actual production run. Generally the Abloy part approval process for mechanical parts has been linked to the Abloy product development process. The responsibilities and documentation to be provided in each step have been defined in the process flow. Picture 1 Main process flow of the Abloy Part Approval Process Generally APAP is required any time a new part is issued. Requirements comes from the customer and have been indicated in the specifications. APAP shall apply to internal and external organization sites that manufactures parts. For the bulk materials, APAP is not required unless specified by the customer. APAP process is applicable in case of: Case Type Requirement Tooling, production, or equipment transferred to a different site / supplier Material change to nonequivalent Table 1 - Case types / requirements Design Documents Design For Manufacturing DFM Gage R&R First Article Inspection Report (FAI) New part or product x x x x x x x x New process or technology x x x x x x x x Copy tool x x x x x Correction of non-conformance x x Sample Parts Cpk study / Verification run Reference & limit Samples x x x x Approval Report x x x x x x 3

4 Two APAP submission levels have been defined. Levels are defined in the product design phase based on the item function criticality. The level has been defined in the d drawing note. Level 1 Level Definition Abloy designed components without critical product function, robust design. (E.g. covers, fasteners, support parts, etc.). Components without ongoing inspection or SPC requirements. Components with high ranking feature(s) in the sensitivity analysis Components which are related to - critical product function - complex design - long tolerance chain - Visual quality requirements Design is based on the tolerance analyze. Statistical tolerancing and Cpk requirement can be used when; - Assembly tolerance is equal to the square root of the sum of the squares of the individual tolerances. Tol assembly n i1 T i T 1 T T3... T n Table - Approval level definition Requirements in different APAP submission levels. Requirements Level 1 Level 1. Design Document (D & 3D file) C C. Design For Manufacturing (DFM) S S 3. Gage R&R (variable and/or attribute) S** 4. First Article Inspection Report (FAI) S*** S 5. Sample Parts S S 6. Cpk Study/ Report S 7. Verification run/ Report S 8. Reference & limit Samples C * C * 9. Production Control Plan S 10. Approval Report C C Table 3 APAP Submission levels *) Optional, supplier prepares and customer approves **) Dimensions with on-going or statistical requirement ***) If numbered dimensions in drawing C = Customer shall provide S = Supplier shall provide 4

5 3D file is the master document for part production. Manufacturing of undefined features are according to 3D file. For tolerances, see D drawing. 3D model formats that can be used:.sldprt,.igs,.step or parasolid D drawing is the document that defines requirements of the individual part. Description of dimension type 1. Numbered Dimensions with Black Diamond symbol (see pic., pos.1). Numbered Dimensions with White Diamond symbol (see pic., pos.) 3. Numbered dimensions (without diamond symbol) with ON-GOING inspection requirement on drawing note (see pic., pos.4) 4. Numbered dimensions (without diamond symbol) with VERIFICATION RUN requirement on drawing note (see pic., pos.3) 5. Numbered dimensions without diamond symbol (see pic., pos.3) Table 4 - Description of the dimensions First Article Inspection Report for approval (FAI) Cpk Study report Verification run Report On-going inspection procedure defined in Control Plan On-going statistical control (SPC) defined in Control Plan Gage R&R X X X X X X X X X X X X X X 5

6 Pos.3 Pos.3 Pos.4 (+Pos.3) Pos. Pos.1 Pos.3 Pos.3 Pos.4 Pos. Pos.1 Picture - Example of the d Drawing Pos.3 Pos.4 Pos. Picture 3 - Example of drawing note Pos.1 6

7 In case of tool manufacturing, manufacturer/ supplier shall provide the tooling information and manufacturability feedback of the product design to the customer. Customer will update the 3d model based on proposed modifications in product design limits. DFM must show the basic concept of the tool used produce the parts (e.g. gate, ejector pin locations, split line etc.), and shall provide together with the quotation. It is preferred to use Power Point slides as the example below. Table 3 - Example of the DFM 7

8 Gage R&R is a mathematical method of determining how much the variation within the measurement process contributes to specifications or overall process variation. A gage R&R study helps to investigate: Whether your measurement system variability is small compared with tolerances or process variability. How much variability in the measurement system is caused by differences between operators. Whether your measurement system is capable of discriminating between different parts. Note! Variable Gage R&R is an analysis of the measurement process, not an analysis of the people. In case of visual requirements in part Attribute Gage R&R test for OQC inspection is recommended. Typically variable Gage R&R is performed by -person study Each person randomly measures 10 marked samples per trial Each person perform up to trials Test needs to apply to the critical dimensions which have been defined in the d drawing. The guidelines for acceptance of Gage R&R: Gage R&R result must be max. 10% of tolerance zone. Approved result Marginal gages between 10% and 30% of tolerance zone. Result need to be approved separately by customer. Gages with R&R 30% or over Results are not acceptable for reliable control / inspection and measurement system needs improvement. The observed variation in process output measurements is not simply the variation in the process itself. It is the variation in the process plus the variation in measurement that results from an inadequate measurement system. The Gage R&R shall be done for dimensions with statistical and on-going requirements. Supplier shall provide the result of the gage R&R with the measurement report. NOTE! Exceptions in R&R rules in chapter 6. 8

9 The parts used for the dimensional data need to be from production tooling and they are picked from a run driven with production parameters. The measurement report need to include: All dimensions numbered in the drawing (measurement 10pcs / cavity). Numbers must correlate with the numbers found in the D drawing. All applicable notes that have variable dimensions (heat treatment, thickness of surface treatment, etc.) In case of multi cavity tools, each cavity needs to be filled individually to their own sheets in the FAI report. To be sure that Cpk study and ongoing production inspections are capable of fulfilling the required specification, the diamond dimension and ongoing production inspection dimensions are restricted to 75% of the total tolerance area. Abloy measuring template, attachment First Article Inspection Report Picture 4 FAI Report Sample parts are delivered together with the measurement (FAI) report submission and should be the same parts as measured in the measurement (FAI) report. Default quantity of the samples is 10 pcs / cavity unless otherwise agreed. 9

10 The purpose of the Cpk study is to determine if the production process is capable to manufacturing parts to customer requirements. Cpk dimensions have been defined in the d drawing, refer For the Cpk report customer template Cpk Report Template Attachment 3 Verification Run / Cpk Report can be used. Subgroups are the preferred method of determining Cpk in most of the cases. There are two primary indexes to determine process capability; Process capability (Cpk) and performance (Ppk). Minimum acceptable value for process approval is Cpk 1.67 NOTE! In case of multi cavity tool, see chapter 6 Capability index calculations are based on the assumption that data is normally distributed. In order for the Cpk index to be used for evaluation of the capability of the process, normality of the measurement data need to be verified. A p value of < 0,05 in a A-D normality test on a APAP Cpk report template indicates that the data does not follow the normal distribution. When data distribution is not normal, Cpk statistic should be ignored and need to be analyzed by an Abloy representative prior to process approval. 1. Process Capability (Cpk) is a calculated index of the inherent capability of a manufacturing process able to consistently produce parts that meet the required design specifications. USL x x LSL C min ; pk 3* sst 3* sst s ST = The estimate of short term standard deviation. USL = Upper specification limit LSL = Lower specification limit x = The average of subgroup averages. s The estimate of short term standard deviation ( ST ) of a stable process using the average range of subgroup samples taken from the process, usually within the context of control charts. s ST R / d R d = The average of subgroup ranges = divisor of R depending subgroup size. Tabled in appendix A 10

11 . Process Performance (Ppk) is a measure of the performance of a process able to consistently produce parts that meet the required design specifications. Ppk indicates past performance and it will be used to follow up the long run production performance. USL x x LSL P min ; pk 3* ˆ ˆ t 3* t Where: ˆ t = The estimate of long term standard deviation of process (sigma estimate) USL = Upper specification limit LSL = Lower specification limit x = The average of subgroup averages. ˆ The estimate of long term standard deviation ( t ) of a process using the sample standard deviation of a set of individuals about the average of the set. This is the estimate of the total variation of the process. s LT n i1 N 1 x x 1 ˆ t s LT x x x x... x x 1 N N 1 ˆ t s = Total variation of measured values LT x = The average of measured values x ˆ N t = An individual measured value. = The estimate of long term standard deviation of process 11

12 Between Subgroup Total Variation Total Vartion Subgroup Average Within Subgroup (Short Term) Variation Picture 5 - Short / long term deviation Minimum requirement for capability studies is 10 sub-groups containing 50 samples consecutively from a production run. If there isn t any clear time interval to collect the samples for the Cpk, sample size of 50 pcs can be picked up randomly from the production batch. In that case they can be the same as 50 sub-groups in the calculation. Picture 6 Sampling plan 1

13 Verification Run Report is used for dimension mentioned in drawing note with verification run requirement (see pic., pos.3). The data is either from time series or randomly collected samples. Total amount of measured parts = 50 pcs. x number of cavities. NOTE! No Cpk requirement. In case of multi cavity tool, see chapter 6 Reference Samples should be delivered with or before APAP submission. Reference samples are used for identification purposes and are not necessarily perfect samples. They present the average acceptable quality level of parts to meet the specifications. Samples need to be collected from a batch produced with production process parameters. A minimum of 3 samples should be included in the APAP submission. Contact your Purchasing representative to determine the proper department to send the samples to. Each sample must be properly tagged and identified as an APAP sample with the minimum information listed below. Identify the sample as an APAP sample Date of manufacturing Item number of the product Limit samples may be proposed by supplier in the Abloy template [attachment #4] in case of visual quality requirements exist in part D drawing with level APAP. Limit samples should be collected from the verification / Cpk run with all the specified data fulfilled in the template. Three equal sets of samples per defect type should be prepared for approval. Customer will sign and provide one copy for supplier. 13

14 The Supplier shall have a Control Plan that defines all methods used for process control and complies with customer specified requirements. The Control Plan is a documented description of the system for controlling part and process quality by addressing their key characteristics and engineering requirements. Control Plan shall be provided to Abloy representative with other Approval Reports (Verification / Cpk Report). The Control Plan should address at least the following: Names of manufacturing processes/ inspection phases (including OQC). Product specifications Measuring / inspection method / equipment Sampling Size and Frequency Picture 8 example of control plan Approval Report document, attached file Part Approval Template, will be prepared by the operational responsible of the customer. The document includes all the reports related to part approval. Any deviations in approval requirements shall be marked in the Approval Report document. Picture 7 - Approval report 14

15 When indicated by the black diamond symbol in D drawing, Statistical Process Control charts should be used for process monitoring. A Supplier shall determine and implement proper measurements (incl. sample size and inspection frequency) that are necessary for controlling these processes and are described in the control plan (5.4). When a dimension or Visual Quality specification requires ongoing inspection, it is mentioned in D drawing note, (see pic.). Supplier shall determine and implement proper inspection procedures (incl. sample size and inspection frequency) that are necessary for monitoring these requirements. All inspection procedures shall be described in the control plan (5.4). The quality records shall be kept for at least two years by supplier unless otherwise specified and must be readily accessible upon request by Abloy representative. Production Ongoing Measurement Data Gage Repeatability & Reproducibility Analysis Data (R&R test results) Capability and Statistical Process Control Data 15

16 By agreement with Abloy representative, Gage R&R or/ and Verification run/ Cpk -reporting requirements for level process approval can be reduced under certain circumstances: 1. In the case of a multi cavity tool, process approval can be based on Verification run/ Cpk study - report of one specified cavity only.. In the case of similar items which are manufactured by common manufacturing process, and have similar or identical verification requirements, process approval can be based on Verification run/ Cpk study of one specified item. 3. If the part will be manufactured by statistically controlled process, the capability of which is already known and proved in connection with manufacturing of similar parts, process approval can be based on the history of process data. Documented evidence of the capability of the manufacturing process shall be provided to an Abloy representative. (E.g. Cpk calculations based on the existing SPC data). 1. In case of multiple, similar ongoing/ SPC dimensions which are measured by a common measurement routine, it is not necessary to perform gage R&R for each dimension separately. Sufficient confidence of the capability of the measurement system (for this specific dimension type) can be reached by performing R&R test for one specified dimension only.. If capability of measurement system is already known and proved by using gage R&R test for identical features and measurement routines, measurement system can be approved based on existing R&R results. Documented R&R results shall be provided to Abloy representative. NOTE: Any deviations from the approval requirements must always to be agreed with an Abloy representative. All agreed deviations from the approval requirements shall be documented in D drawing note by Abloy R&D. Individual FAI report for each item and cavity is mandatory without deviations! 1. Variable Gage R&R (Excel workbook). First Article Inspection Report (Excel workbook) 3. Verification run / Cpk report (Excel workbook) 4. Limit sample board template (ppt) 16

17 Only the document and template versions that can be found on the Abloy website are valid and shall be used. All APAP documents and templates are available to download from: From ASTM Publication STP-15D, Manual on the Presentation of Data and Control Chart Analysis 1976 The process from which the data is collected from is statistically stable The individual measurements from the process data form an approximately normal distribution A sufficient number of parts must be evaluated in order to capture the variation that is inherent in the process The specifications based on customer requirements. 17

18 Data set: data point dim data point dim data point dim data point dim data point 1 30, , , , ,31 30, , , , , , , , , , , , , , , , , , , , , , , , ,9 7 30, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,8 0 30, , , , , , , , , ,50 30, , , , , , , , , , , , , , , , , , , ,40 dim 18

19 Process Capability Process Data LSL 9,5 Target 30,5 USL 31,5 Sample Mean 30,5314 Sample N 15 StDev (Within) 0,18099 StDev (O v erall) 0, LSL Target USL Within Overall Potential (Within) C apability C p 1,84 C PL 1,90 C PU 1,78 C pk 1,78 O verall C apability Pp 1,76 PPL 1,8 PPU 1,71 Ppk 1,71 C pm 1,74 9,7 30,0 30,3 30,6 30,9 31, 31,5 Probability Plot Normal Percent 99, Mean 30,53 StDev 0,189 N 15 AD 0,63 P-Value 0, ,1 30,0 30, 30,4 30,6 30,8 31,0 31, Xbar-R Chart 30,8 UC L=30,7804 Sample Mean 30,6 30,4 _ X=30,5314 LC L=30, Sample Sample Range 0,8 0,6 0,4 0, UC L=0,913 _ R=0,43 0,0 LC L= Sample

20 Example of Cpk calculation: USL x x LSL C min ; pk 3* sst 3* sst Target = 30.5±1 USL = 31.5 LSL = 9.5 Average of subgroup averages x = Average of subgroup ranges R = Subgroup size = 5 => d =.36 (see appendix, table 1.) StDev (Within) s ST = R / d = 0.408/.36 = C 1,78; 1, 9 pku C pkl 3* *0,1809 C pk 1.78 Example of Ppk calculation: USL x x LSL P min ; pk 3* ˆ ˆ t 3* t Target = 30.5±1 USL = 31.5 LSL = 9.5 Average of averages x = StDev (Overall) ˆ = t s s LT LT slt n i1 N 1 x x 1 ˆ x x x x... x x t 1 N (151) N ˆ t ˆ t P 1.71; 1, 8 pku 3* P pkl 3*0.189 Ppk

21 Change history Rev Date Author Remarks rev JM / OPK rev OPK 5.3 added. R&R requirement expanded to all ongoing dimensions. rev OPK Verification Run requirement clarified rev OPK R&R requirement removed from Verif.Run dimensions (4.4. / table4). rev OPK 5.4 Requirement of Control Plan delivery added rev OPK table : Level 1 requirements clarified (Ongoing / SPC requirement). rev OPK 4. DFM requirement clarified. rev mikkra chapters.1 & 4.9 added rev OPK Table 3 updated, chapter 6&8 added, chapter 4.6 updated Rev OPK Verification run requirement removed from ongoing dimensions. 1