Gage R&R and Capability - Between 10% and 30% and cannot be improved

M

Michel Saad

#1
Question:

I have once read (I think) that if the gage R&R is between 10% and 30% and cannot be improved, a correction of the capability indices has to be done. Does anyone know the formula to how the Cp, k and Cpk are corrected?

Thanks.
 
Elsmar Forum Sponsor
M

Michel Saad

#3
For those interested, I found it (with no small effort I might add).

It is in the word file attached since I couldn't paste the image directly. It is only applicable to the Cp since % R&R is not dependent on the target.

I am intoducing into our Cp, Cpk, k policy that if a measuring equipment has a gage R&R between 10% and 30%, the equipment can be used but the Cp has to be corrected until the measuring equipment can be corrected.

Cpo is the measured Cp where Cp is the process capability once the measurement equipment uncertanty is removed. You will notice that for % R&R values of less than 10%, Cpp and Cpo are practically the same. It is for values of 20 to 30% that the formula is usefull.

Hope it helps.
 

Attachments

Marc

Hunkered Down for the Duration
Staff member
Admin
#4
Thanks, Michel! The contribution is appreciated. I'm sorry no one here knew the answer. :thedeal:
 

Atul Khandekar

Quite Involved in Discussions
#5
R&R to Cpk

This one I had downloaded from pdf zone or from dWizard's (I dont remember correctly). Its a small article on relationship between R&R and Proces Capability.

Hope this helps.

- Atul.
 

Attachments

Thread starter Similar threads Forum Replies Date
S Capability or Gage R&R Study for Leak Tester? Reliability Analysis - Predictions, Testing and Standards 15
O Capability or Gage R&R Study for Leak Tester Reliability Analysis - Predictions, Testing and Standards 11
V Supplier Capability and 100% Sort causing Gage Wear APQP and PPAP 1
D AIAG 4th Edition Capability Study and Gage R&R Requirements Document Control Systems, Procedures, Forms and Templates 8
E Capability of Gage (Cg & Cgk) for New and Repaired Gages Capability, Accuracy and Stability - Processes, Machines, etc. 10
B MSA (Gage R&R) vs. Capability Cpk Study - Helium Leak Check Station Statistical Analysis Tools, Techniques and SPC 2
T Machine GR&R (Gage R&R) - Capability Study Capability, Accuracy and Stability - Processes, Machines, etc. 5
F Process Capability on go / no-go gage? Capability, Accuracy and Stability - Processes, Machines, etc. 1
S Operator Capability - Gage R&R Poor Repeatability Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 8
Y Product Stability (Machine Capability) vs. Equipment Repeatability (Gage R&R) Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 7
I What is Gauge Capability? Dial Thickness Gage and Digital Vernier Calipers Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 17
O Gage Block Wringing General Measurement Device and Calibration Topics 3
B Gage R&R with NDC=1 Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 19
S Type 1 Gage R&R or something else? Reliability Analysis - Predictions, Testing and Standards 6
G Should I perform Gage R&R only at the beginning of a new project? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 6
V Thread Plug Gage Pitch GO Diameter out of spec AQL - Acceptable Quality Level 8
G Gage R&R - Where am I going wrong? Part of a FAIR submission (Aerospace) Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 2
R Gage R&R Excel templates Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
K Gage R&R with more than 3 appraisers Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 2
Anerol C Gage R&R Template AIAG 4th Edition IATF 16949 - Automotive Quality Systems Standard 3
T Attributes SPC study - Attributive control (Go gage) Statistical Analysis Tools, Techniques and SPC 5
N % Tolerance - Type 1 study on the gages, then a gage R&R (ANOVA) Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 4
M Definitive answer on Type 1 vs Type 2 vs Type 3 Gage Study Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 0
V Gage Management and Gage R&R Software General Measurement Device and Calibration Topics 1
D Gage R&R Study on Load Cells - Large chemical blending tanks IATF 16949 - Automotive Quality Systems Standard 1
B Minitab Type 1 Gage Study on True Position Question Measurement Uncertainty (MU) 1
S Gage R&R on alloy Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 10
8 Need Help - Runout - Function Gage Inspection, Prints (Drawings), Testing, Sampling and Related Topics 7
L Gage R&R studies for identical Devices - Need to confirm the requirement to perform them Reliability Analysis - Predictions, Testing and Standards 2
G Stab Pin Size For Check Gage Inspection, Prints (Drawings), Testing, Sampling and Related Topics 3
E Functional Gage for TOP applied at RFS Design and Development of Products and Processes 5
F No reproducibility Error in Gage R&R? Reliability Analysis - Predictions, Testing and Standards 4
M Template for Attribute Gage R & R wanted Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
G Warning about Deltronic Gage Pins - The "Certification of Accuracy" document General Measurement Device and Calibration Topics 13
A Gage type 1 study on CMM Capability, Accuracy and Stability - Processes, Machines, etc. 2
Q Gage R&R for Instant Measurement Machine Manufacturing and Related Processes 6
M Gage R&R with large inter part variance - Torque Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 7
D Do we need normal data for gage r&r studies? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 5
D Do I need part variation while doing Destructive Variable Gage R&R MSA study Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 19
S Gage R&R Standard Deviations Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 6
J Informational Gage R&R: Swapping operators Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 5
S Gage R & R for large amount of inspections IATF 16949 - Automotive Quality Systems Standard 10
S Ring Gage Thermal Expansion General Measurement Device and Calibration Topics 4
L Gage R&R for test precision or uncertainty prediction? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 2
S Minor diameter of threaded ring gage General Measurement Device and Calibration Topics 1
A Does Torque Gage Need Validation? Reliability Analysis - Predictions, Testing and Standards 4
J Ignoring a Failed Gage R&R and upcoming external audit IATF 16949 - Automotive Quality Systems Standard 22
R Scaling a Gage R&R - 2 holding fixtures each with 10 nests Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 7
B Gage R&R Acceptable (10-30%), deduct Total Variation from Tolerance Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 12
apestate Inexpensive Gage Blocks for small aerospace startup shop General Measurement Device and Calibration Topics 1

Similar threads

Top Bottom