The Cove Business Standards Discussion Forums
Cp vs. Cpk - A Visual Animation and Related Discussion Threads
Please read this thread...
Software update
Cp vs. Cpk - A Visual Animation and Related Discussion Threads
Go Back   The Elsmar Cove Business Systems and Standards Discussion Forums > >
Forum Username

Elsmar Cove Forum Visitor Notice(s)

Wooden Line

Cp vs. Cpk - A Visual Animation and Related Discussion Threads - Page 2

Monitor the Elsmar Forum
Courtesy Quick Links


Links Elsmar Cove visitors will find useful in the quest for knowledge and support:

Jennifer Kirley's
Conway Business Services


Howard's
International Quality Services


Marcelo Antunes'
SQR Consulting, and
Medical Devices Expert Forum


Bob Doering
Bob Doering's Blogs and,
Correct SPC - Precision Machining


Ajit Basrur
Claritas Consulting, LLC



International Standards Bodies - World Wide Standards Bodies

AIAG - Automotive Industry Action Group

ASQ - American Society for Quality

International Organization for Standardization - ISO Standards and Information

NIST's Engineering Statistics Handbook

IRCA - International Register of Certified Auditors

SAE - Society of Automotive Engineers

Quality Digest

IEST - Institute of Environmental Sciences and Technology


Some Related Topic Tags
cpk (related to process capability), process capability
Reply
 
Thread Tools Search this Thread Rating: Thread Rating: 2 votes, 4.50 average. Display Modes
  Post Number #9  
Old 12th January 2015, 02:01 AM
reynald's Avatar
reynald

 
 
Total Posts: 283
Re: Cp vs. Cpk - A Visual Animation and Related Discussion Threads

For analysis yes because it would be very meaningful to compare them.
Case 1: Cp = 1.5, Cpk = 0.98 --> your problem is centering
Case 2: Cp = 0.98, Cpk = 0.98 --> your process is perfectly centered, your problem is variation
Thank You to reynald for your informative Post and/or Attachment!

Sponsored Links
  Post Number #10  
Old 12th January 2015, 02:32 PM
Bev D's Avatar
Bev D

 
 
Total Posts: 3,614
Re: Cp vs. Cpk - A Visual Animation and Related Discussion Threads

and of course, a simple look at the data will tell you the same thing and a whole lot more. no need to go through the calculations (unless of course your customers are requiring the numbers.)
  Post Number #11  
Old 12th January 2015, 03:32 PM
Mikael

 
 
Total Posts: 214
Re: Cp vs. Cpk - A Visual Animation and Related Discussion Threads

Lol good point, but what if I want to see some kind of trendanalyze over time, then the numbets would be nice?
  Post Number #12  
Old 12th January 2015, 04:02 PM
Bev D's Avatar
Bev D

 
 
Total Posts: 3,614
Re: Cp vs. Cpk - A Visual Animation and Related Discussion Threads

yes of course the actual numbers would be useful. trend the data not the Cp/Cpk index. a simple run chart of multi-vari is the best place to start, then you can add statistical control limits.

W. Edwards Deming said it best: "plot the bloody dots". in other words, forget the math, plot the data.
Thanks to Bev D for your informative Post and/or Attachment!
  Post Number #13  
Old 12th January 2015, 05:19 PM
LUV-d-4UM

 
 
Total Posts: 769
Re: Cp vs. Cpk - A Visual Animation and Related Discussion Threads

Bev,
I like your comment. We do 100% inspection. But the TS auditor wants to see trending chart. So we just comply.
  Post Number #14  
Old 13th January 2015, 05:08 PM
Mikael

 
 
Total Posts: 214
Re: Cp vs. Cpk - A Visual Animation and Related Discussion Threads

Reynald: for case 2 did you mean cpk 0,98???
  Post Number #15  
Old 15th January 2015, 12:32 PM
reynald's Avatar
reynald

 
 
Total Posts: 283
Re: Cp vs. Cpk - A Visual Animation and Related Discussion Threads

What I meant is that if your Cp failed then you sure have variation issues.
If Cp is good and only Cpk failed, then the problem could be easier as you need only to do some centering adjustments (centering a process is not always easy but more often easier than reducing variation).

Note that case 3 where Cp<Cpk dont exist. Cpk can only be as high as Cpk and that occurs when mean is perfectly centered.
Thanks to reynald for your informative Post and/or Attachment!
  Post Number #16  
Old 9th April 2018, 04:10 AM
Zk_Shazly

 
 
Total Posts: 1
Re: Cp vs. Cpk - A Visual Animation and Related Discussion Threads

CP indicates the consistency of the process whatever if it achieves its target or not
CPk indicates both consistency & achieving target of the process
Reply

Lower Navigation Bar
Go Back   The Elsmar Cove Business Systems and Standards Discussion Forums > >

Bookmarks



Visitors Currently Viewing this Thread: 1 (0 Registered Visitors (Members) and 1 Unregistered Guest Visitors)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Forum Search
Display Modes Rate Thread Content
Rate Thread Content:

Forum Posting Settings
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Emoticons are On
[IMG] code is On
HTML code is Off


Similar Discussion Threads
Discussion Thread Title Thread Starter Forum Replies Last Post or Poll Vote
FORM Specific Discussion Threads Marc Document Control Systems, Procedures, Forms and Templates 14 30th September 2013 02:59 PM
Discussion Threads - Threads Moved from one forum to another fallon Forum Software - How to Do Things in the Elsmar Forum --> Instructions 6 27th August 2009 06:45 PM
Document Control Procedures and Related Discussion Threads Marc Document Control Systems, Procedures, Forms and Templates 2 3rd July 2009 08:23 AM
'Similar Discussion Threads' box moved harry Forum News and General Information 21 3rd January 2008 01:10 PM
PROCEDURE Specific Discussion Threads Marc Document Control Systems, Procedures, Forms and Templates 0 1st October 2006 03:34 PM



The time now is 09:52 PM. All times are GMT -4.
Your time zone can be changed in your UserCP --> Options.



Misc. Internal Links


NOTE: This forum uses "Cookies"