The Elsmar Cove Wiki More Free Files The Elsmar Cove Forums Discussion Thread Index Post Attachments Listing Failure Modes Services and Solutions to Problems Elsmar cove Forums Main Page Elsmar Cove Home Page
Go Back   The Elsmar Cove Forum > Common Quality Assurance Processes and Tools > Supplier Quality Assurance and other Supplier Issues
Forum Username


Search the Elsmar Cove
Custom Search
Monitor the Elsmar Forum
Follow Marc & Elsmar
Elsmar Cove Forum RSS Feed  Marc Smith's Google+ Page  Marc Smith's Linked In Page   Marc Smith's Elsmar Cove YouTube Page  Marc Smith's Facebook Page  Elsmar Cove Twitter Feed
Elsmar Cove Groups
Elsmar Cove Google+ Group  Elsmar Cove LinkedIn Group  Elsmar Cove Facebook Group
Sponsor Links





Donate and $ Contributor Forum Access

Courtesy Quick Links

Links that Elsmar Cove visitors will find useful in your quest for knowledge:

Howard's
International Quality Services
Marcelo Antunes'
SQR Consulting
Bob Doering's
Correct SPC - Precision Machining

NIST's Engineering Statistics Handbook
IRCA - International Register of Certified Auditors
SAE - Society of Automotive Engineers
Quality Digest Portal
IEST - Institute of Environmental Sciences and Technology
ASQ - American Society for Quality

Related Topic Tags
ppm (parts per million), qms (quality management system), reject rate, supplier performance, supplier control and monitoring, metrics (measurables such as for objectives)
Reply
 
Thread Tools Search this Thread Rate Thread Content Display Modes
  #1  
Old 28th August 2009, 01:54 AM
jperez25 jperez25 is offline
Getting Involved (6 to 9 Posts)

 
Registration Date: Mar 2005
Location: China
Age: 38
 
Posts: 8
Thanks Given to Others: 0
Thanked 2 Times in 1 Post
Karma Power: 39
Karma: 20
jperez25 has less than 100 Karma points so far.
Please Help! When to start counting supplier PPM? Supplier Performance Metrics

Hi there. I have a question that I know does not have a black or white answer, but I'm basically looking for any interesting insights.

One of the metrics we use to measure supplier performance is supplier PPM, calculated in the conventional way or reject rate per million.

Now our systems are similar to B3, where we require our suppliers to submit a PPAP before starting production and then we have a further Job#1 date of the new product, which usually happens 3-4 months after our suppliers submit their PSWs. In this period of time we run our pre-production, which are saleable units to the customer.

Our current process is that anything that is rejected in the plant (IQ or in process) is considered in the supplier PPM calculation.

However, there is a question to whether we should only consider rejected parts after the Job1, since the first pre-production lots have a greater risk of quality issues (though supplier PSW should have been signed at this point of time).

Then the question is, considering the following two alternatives, which one is the one that represents more the supplier quality:
1) A metric that includes every rejected part when calculating the reject rate (this could include pre-series, prototypes, etc)?
2) A metric that include rejected parts after a 'stabilization period' of 3-4 months after supplier PSW?

The two options actually measure different things, Any of you see any particular benefit of using either one of the methods?

Javier

Sponsored Links
  #2  
Old 28th August 2009, 08:00 AM
Kales Veggie's Avatar
Kales Veggie Kales Veggie is offline
People: The Vital Few

 
Registration Date: Dec 2006
Location: Fort Wayne, IN
 
Posts: 973
Thanks Given to Others: 130
Thanked 574 Times in 386 Posts
Karma Power: 138
Karma: 4715
Kales Veggie is appreciated, and has over 1700 Karma points.
Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.
Re: When to start counting supplier PPM?

All rejects. Very simple. Why is it OK for supplier to send in rejects during the first 4 months?

If APQP/FMEA/Control Plan/PPAP/GP12(or similar) are done effectively, why would there be any rejects from your supplier?

A reject is a reject.....same goes for proto-types.

__________________

Kees de Wit
Auditor/Consultant
People: The vital few
Sponsored Links

  #3  
Old 28th August 2009, 11:28 AM
Jim Wynne's Avatar
Jim Wynne Jim Wynne is offline
Cross Forum Moderator

 
Registration Date: Jan 2005
Location: Southeast Wisconsin
 
Posts: 14,077
Thanks Given to Others: 2,051
Thanked 5,993 Times in 3,820 Posts
Blog Entries: 2
Karma Power: 1531
Karma: 42502
Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.
Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.
Re: When to start counting supplier PPM?

Quote:
In Reply to Parent Post by Kales Veggie View Post

All rejects. Very simple. Why is it OK for supplier to send in rejects during the first 4 months?

If APQP/FMEA/Control Plan/PPAP/GP12(or similar) are done effectively, why would there be any rejects from your supplier?

A reject is a reject.....same goes for proto-types.
The reason for rejection is important; sometimes in the prototype or pre-production phase the design is fluid and things get thrown out that aren't necessarily the fault of the supplier. During this period of time, the objective should be design validation, and the less finger-pointing and blame-seeking the better.

As to the OP's question, I don't think that PPM makes any sense at all unless you're actually dealing with millions of things. We ask suppliers to insure that their processes are stable and capable, but both of those things are based on the concept of randomness. If there's (for example) only a chance of 100 in 1,000,000 that any defect will occur, it doesn't mean that 1,000,000 individuals must be created in order to see the 100 defects. This means that if a supplier's PPM rate is 1000 today, it might not be 1000 after a million iterations. The point is that if we can't know what the actual rate might be after a million chances, there's no sense in using estimates that don't take long-term randomness into account.

__________________

It is difficult to get a man to understand something, when his salary depends upon his not understanding it. --Upton Sinclair
  #4  
Old 30th August 2009, 01:29 PM
Kales Veggie's Avatar
Kales Veggie Kales Veggie is offline
People: The Vital Few

 
Registration Date: Dec 2006
Location: Fort Wayne, IN
 
Posts: 973
Thanks Given to Others: 130
Thanked 574 Times in 386 Posts
Karma Power: 138
Karma: 4715
Kales Veggie is appreciated, and has over 1700 Karma points.
Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.Kales Veggie is appreciated, and has over 1700 Karma points.
Re: When to start counting supplier PPM?

Quote:
In Reply to Parent Post by Jim Wynne View Post

The reason for rejection is important; sometimes in the prototype or pre-production phase the design is fluid and things get thrown out that aren't necessarily the fault of the supplier. During this period of time, the objective should be design validation, and the less finger-pointing and blame-seeking the better.

As to the OP's question, I don't think that PPM makes any sense at all unless you're actually dealing with millions of things. We ask suppliers to insure that their processes are stable and capable, but both of those things are based on the concept of randomness. If there's (for example) only a chance of 100 in 1,000,000 that any defect will occur, it doesn't mean that 1,000,000 individuals must be created in order to see the 100 defects. This means that if a supplier's PPM rate is 1000 today, it might not be 1000 after a million iterations. The point is that if we can't know what the actual rate might be after a million chances, there's no sense in using estimates that don't take long-term randomness into account.
Very simple again. Then it is not the fault of the supplier, but engineering or purchasing or whoever.

A supplier reject is a supplier reject.

__________________

Kees de Wit
Auditor/Consultant
People: The vital few
  #5  
Old 30th August 2009, 03:29 PM
Jim Wynne's Avatar
Jim Wynne Jim Wynne is offline
Cross Forum Moderator

 
Registration Date: Jan 2005
Location: Southeast Wisconsin
 
Posts: 14,077
Thanks Given to Others: 2,051
Thanked 5,993 Times in 3,820 Posts
Blog Entries: 2
Karma Power: 1531
Karma: 42502
Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.
Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.Jim Wynne is appreciated, and has over 1700 Karma points.
Re: When to start counting supplier PPM?

Quote:
In Reply to Parent Post by Kales Veggie View Post

Very simple again. Then it is not the fault of the supplier, but engineering or purchasing or whoever.

A supplier reject is a supplier reject.
What you don't seem to understand is that in the early stages, things can be very ambiguous, and move so quickly that it's difficult (and senseless) to try to ascribe blame. What's the point in starting the PPM clock when the product might be substantially different when real production begins? We all know that part of what got the US auto industry in trouble was (is?) their inveterate finger-pointing and blame-seeking. Why encourage it?

__________________

It is difficult to get a man to understand something, when his salary depends upon his not understanding it. --Upton Sinclair
Thanks to Jim Wynne for your informative Post and/or Attachment!
Reply

Lower Navigation Bar
Go Back   The Elsmar Cove Forum > Common Quality Assurance Processes and Tools > Supplier Quality Assurance and other Supplier Issues

Do you find this discussion thread helpful and informational?


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
Smilies 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
Supplier Performance Measurement PPM (parts per million)? petem Benchmarking - Methods and General Discussions 10 15th August 2011 04:17 AM
Automotive Supplier Benchmarking - Supplier PPM Data babyface Benchmarking - Methods and General Discussions 5 15th November 2010 09:52 AM
Supplier Performance - Recording Supplier Performance for long term trend reporting KAMay ISO 9000, ISO 9001, and ISO 9004 - Questions and Discussions 8 16th February 2010 05:34 AM
Supplier Scorecard Metrics - Supplier PPM Quality Defects pammesue Supplier Quality Assurance and other Supplier Issues 12 15th August 2008 12:28 PM
Supplier Defects Per Million Metric - Best way to depict monthly supplier performance quality_ab Supplier Quality Assurance and other Supplier Issues 3 14th January 2005 08:24 AM



The time now is 12:55 PM. All times are GMT -4.
Your time zone can be changed in your UserCP --> Options.


   


Marc Timothy Smith - Elsmar.com
8466 LeSourdsville-West Chester Road, Olde West Chester, Ohio 45069-1929
513 341-6272