SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in place?

howste

Thaumaturge
Super Moderator
#21
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

100% Inspection is justifiable only in aerospace&medical Products. .If you depend on it in automotive and consumer industry.You cannot stand in the global competition.The success of japanese is there to see for all of us.
V.J.Brahmaiah
That's an interesting rule you've made up. I disagree. 100% inspection is justifiable in any industry based on risk and cost.
 
Elsmar Forum Sponsor

Stijloor

Staff member
Super Moderator
#22
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

100% Inspection is justifiable only in aerospace&medical Products. .If you depend on it in automotive and consumer industry.You cannot stand in the global competition.The success of japanese is there to see for all of us.
V.J.Brahmaiah
One of my Clients (very well-known Japanese) inspects all product at the end of the production line due to inherent, unavoidable process issues.

Stijloor.
 

bobdoering

Stop X-bar/R Madness!!
Trusted Information Resource
#23
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

As a goal, 100% inspection is to be avoided - but it can only be avoided for mission critical characteristics by elimination of all special causes. Good luck. Whether 100% inspection is value added is not the original question - the original question is the converse: Is SPC still value added when 100% inspection is in place. The answer: Yes, because you can verify process control and gain process understanding even while performing 100% inspection.
 

Bev D

Heretical Statistician
Staff member
Super Moderator
#24
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

yes - I worked at a very well known high quality japanese automanufacturer and they too did 100% inspection and poke yoke inspections for many critical characteristics (airbags anyone?) including fit and finish.

I've worked fro high volume consumer product companies and those products can still kill people or kill your company if you don't inspect for certain characteristics....
 
B

brahmaiah

#25
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

That's an interesting rule you've made up. I disagree. 100% inspection is justifiable in any industry based on risk and cost.
I have also said 100% inspection is justifiable in high risk industries like Aerospace and health.By advocating 100% inspection Are we not negating the teachings of (American)quality gurus who taught SPC to the world.
Every one knows Inspection is a non-value added process.
V.J.Brahmaiah
 
Last edited by a moderator:

Jim Wynne

Staff member
Admin
#26
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

I have also said 100% inspection is justifiable in high risk industries like Aerospace and health.By advocating 100% inspection Are we not negating the teachings of (American)quality gurus who taught SPC to the world.
Every one knows Inspection is a non-value added process.
V.J.Brahmaiah
No, everyone does not know that. One of the things that grates on me is the old "100% inspection is only 80% effective" bromide. There's no empirical basis for it--it's just something that people regurgitate in order to avoid thinking about what they're doing.

SPC is about the economic control of processes. That's why Walter Shewhart's landmark book was called Economic Control of Quality of Manufactured Product. His idea, carried forward by Deming, was to (as Deming put it) "eliminate the need for mass inspection." Note that it doesn't say "eliminate the need for inspection." SPC isn't intended to try to make things perfect, or to eliminate all defects, which just isn't possible in the vast majority of cases. The need for inspection (100% or otherwise) should be reduced as far as possible, but to think that it's never necessary or that it's inherently undesirable in all cases is just wrong.
 
V

Vicman

#27
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

I agree on Jim post, and I will add some information to that:

SPC, 100% inspection, and sample plans are some of the tools that are available to us, we have to decide which one to use and fit the best to our purpose of CONTROL.
There is always variation present in all kind of processes. In some cases we need to performance a hundred percent inspection or use SPC techniques, you know all depends.

For example:
“We cannot perform a 100% inspection in destructive or fatigue tests of products such as brakes or wheels” in this case we may use a Weibull distribution curve, as our statistical tool in order to estimate the possibility of a failure to occur.

“A crew from a commercial airline needs to go through a complete characteristic and parameters check list prior to take off” this is a valuable tool also.

Both methods are good is us to decide which one to use.
 

mbehmazia

Involved In Discussions
#28
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

Just adding my two cents. Unless I am missing something, let's take a step back here. With a question such as SPC vs 100% inspection, with that thought process in mind, let's just make 50% of our production all scrap! Don't laugh, why not? Heck, we are sorting it 100% right? Can you imagine such a thing? Always reduction in variation and prevention will win the day vs. detection imho. 100% sorting will not save lost resources such as time, money, material, etc. I am extremely curious on why such a question would even be asked unless you are in between stages meaning the cost of even sending one bad part to your customer could mean lost contracts, etc. !00% is great for a stop-gap measure however, imho, not the norm you want your organization to get use to and comfortable with.
 

bobdoering

Stop X-bar/R Madness!!
Trusted Information Resource
#29
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

Just adding my two cents. Unless I am missing something, let's take a step back here. With a question such as SPC vs 100% inspection, with that thought process in mind, let's just make 50% of our production all scrap! Don't laugh, why not? Heck, we are sorting it 100% right? Can you imagine such a thing?
The question was not 100% inspection OR SPC, it was if you are already doing 100% inspection, is it value added to do SPC, and we showed how yes, that is the case. SPC may take the 50% scrap situation - if that was the current capability - and reduce it if the technology was available.

Always reduction in variation and prevention will win the day vs. detection imho. 100% sorting will not save lost resources such as time, money, material, etc. I am extremely curious on why such a question would even be asked unless you are in between stages meaning the cost of even sending one bad part to your customer could mean lost contracts, etc. 100% is great for a stop-gap measure however, imho, not the norm you want your organization to get use to and comfortable with.
Yes, reducing variation - which SPC can do if performed correctly - is a good thing. But, it is physically impossible for SPC to assure 100% good product on its own. There are 2 reasons for this: 1) SPC is sampling, and 2) there are such things called "special causes". SPC attempts to control common cause variation. It has no control of special causes, and if they occur intermittently, the sampling will not catch them. If your customer has 0 defect requirements (and many do), SPC will NOT ensure 100% good product. Sorry...it is physically impossible. So, yes, an organization may have to get comfortable with it to meet customer requirements. Hopefully, it was built into the costing.
 

mbehmazia

Involved In Discussions
#30
Re: SPC vs. 100% Inspection - Is SPC still value-added when 100% inspection is in pla

Yes, mostly American manufacturers imho. If you have to "get use" to 100% inspection as a norm, again, imho, you should not be in that particular commodity in the first place. I am 100% American, born and raised in Michigan actually. "Getting use to"...100% inspection tells me about an organization's top management support. A cop out imho. Also, "vs" imho does mean one or the other. Of course all of us Quality professionals would never dream (or would hope not) only utilizing only one or the other Quality problem solving tool for any given scenario. My extensive travels have showed me one thing, among many, I would never hear such a thing in some other countries, meaning SPC vs. 100% inspection...all catching up with us now.
 
Thread starter Similar threads Forum Replies Date
K SPC to apply for Particle in Clean Room Class 100 Statistical Analysis Tools, Techniques and SPC 7
R SPC vs. 100% testing Statistical Analysis Tools, Techniques and SPC 1
J SPC in 100% Population - Monitoring Overtime Expenses - Financial Application Statistical Analysis Tools, Techniques and SPC 3
A SPC procedure / flow chart Statistical Analysis Tools, Techniques and SPC 2
P Informational SPC in Batch Processing Statistical Analysis Tools, Techniques and SPC 3
B Handling lower detection limits for SPC and process performance Statistical Analysis Tools, Techniques and SPC 1
A How to reduce the process SPC monitoring Capability, Accuracy and Stability - Processes, Machines, etc. 3
P SPC for machining processes Capability, Accuracy and Stability - Processes, Machines, etc. 1
earl62 What is the best way to control special characteristics in Control plan? Is it Mandatory to have SPC for IATF 16949? IATF 16949 - Automotive Quality Systems Standard 12
J SPC - Stamping parts - Small batch size Statistical Analysis Tools, Techniques and SPC 6
T Attributes SPC study - Attributive control (Go gage) Statistical Analysis Tools, Techniques and SPC 5
S Anyone Familiar with "SPC for Excel" add-in? Lean in Manufacturing and Service Industries 4
G Assignable cause/corrective action list for SPC Software Statistical Analysis Tools, Techniques and SPC 3
H SPC for special characteristics - CSR - Control of SC and CC Statistical Analysis Tools, Techniques and SPC 1
J Determining SPC tolerance Statistical Analysis Tools, Techniques and SPC 21
L SPC - Methods to collect data IATF 16949 - Automotive Quality Systems Standard 7
Marc Steve Prevette's Statistical Process Control (SPC) "Library" Statistical Analysis Tools, Techniques and SPC 0
A SPC for Eddy Current Testing Statistical Analysis Tools, Techniques and SPC 28
S SPC (Statistical Process Control) for Unilateral Tolerance - Questions Statistical Analysis Tools, Techniques and SPC 6
Proud Liberal Informational Use of Classical SPC in Precision Machining Statistical Analysis Tools, Techniques and SPC 9
J Recommendations on Inspection/SPC Software Statistical Analysis Tools, Techniques and SPC 4
Q Real Time Electronic SPC/Control Charting Statistical Analysis Tools, Techniques and SPC 4
Rameshwar25 Other types of Control Charts described in Chapter II of SPC Manual Statistical Analysis Tools, Techniques and SPC 6
A Electric terminal crimping machines - Is SPC appropriate for this process? Manufacturing and Related Processes 4
J Properly understanding SPC - Newbie SPC questions Statistical Analysis Tools, Techniques and SPC 34
bobdoering SPC Charting frequency calculator for X hi/lo chart Imported Legacy Blogs 0
bobdoering Handy training tip for SPC - the Check Engine Light Analogy Statistical Analysis Tools, Techniques and SPC 0
QMMike SPC Software for MAC computers Statistical Analysis Tools, Techniques and SPC 2
Marc SPC based Dashboards - By Steve Prevette (November 2017) Statistical Analysis Tools, Techniques and SPC 1
H SPC Work Instructions (WI) Statistical Analysis Tools, Techniques and SPC 2
S Doubts about SPC taken in Machining - Part has +-0.01 Tolerance Statistical Analysis Tools, Techniques and SPC 5
A Short Term vs. Long Term SPC Study - Where is Cp and Cpk Defined Statistical Analysis Tools, Techniques and SPC 8
E SPC for Dummies - The correct meaning of all the graphs Statistical Analysis Tools, Techniques and SPC 3
Tagin Can/should SPC be applied to Computer Assembly and Software Imaging? Statistical Analysis Tools, Techniques and SPC 8
P Recommendations on SPC Software or Excel SPC add-in(s) Quality Assurance and Compliance Software Tools and Solutions 6
A Not all characteristics follow a Normal Distribution - How do you do SPC Chart Capability, Accuracy and Stability - Processes, Machines, etc. 5
T SPC in Insurance Back Office Operations Service Industry Specific Topics 4
C SPC for Particulate Alert/Action Levels Statistical Analysis Tools, Techniques and SPC 3
E SPC Production - Getting Cpk and Ppk Statistical Analysis Tools, Techniques and SPC 8
M SPC with many data points from one dimension Statistical Analysis Tools, Techniques and SPC 16
Q Mixed data collection (SPC) for different mold cavities Statistical Analysis Tools, Techniques and SPC 2
M How to Start SPC from the ground up! Statistical Analysis Tools, Techniques and SPC 8
bobdoering Available SPC and Metrology Consultants Paid Consulting, Training and Services 0
I SPC on Cyclic Data Statistical Analysis Tools, Techniques and SPC 10
S SPC Card for One Sample Size - Customer requires for all critical dimensions Statistical Analysis Tools, Techniques and SPC 8
R Quality Management & SPC Manufacturing and Related Processes 1
B Is SPC data For Special Characteristics always required? TS 16949 clause 8.1 ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 2
S How to Start SPC in a Shaft Grinding Section Statistical Analysis Tools, Techniques and SPC 1
A I-MR SPC used for Inspection Statistical Analysis Tools, Techniques and SPC 7
E SPC data from multiple Excel files Statistical Analysis Tools, Techniques and SPC 5

Similar threads

Top Bottom