Search results
Results From The WOW.Com Content Network
For the best layout of C=0 vs Z1.4 Mil105 plans, see "Zero Acceptance Number Sampling Plans" by Nicholas L. Squeglia. There are advantages to statistically correct c=0 plans, such as low sample size. But very few people are qualified to "just find a plan that matches what they are doing" and know what their results actually mean in terms of AOQL.
A c=0 sample plan is one in which you do a certain number of samples . If you have zero failures (c) in those n samples, the test passes. If you have one or more failures, the plan fails. Basically, you stop sampling on the first failure.
Re: C=0 I am not sure that it comes from anything in particular. Generally speaking its meaning in sampling plans is as you stated "acceptance". It is the acceptance number or acceptance value used in the sampling plan. In "C=0" no defects can be found in the accepted sample size. In "C=1" one defect can be found, and so forth.
Can anyone offer any advice on this please? I'm working with a supplier on a project to manufacture a medical device for a client. I have suggested that the ANSI Z1.4 Zero Acceptance sampling plan should be used - I have suggested AQL 0.065 c=0, but the manufacturer has said that they normally use AQL 0.40 c=0.
Re: AS9100 Sampling Plan Requirements - 8.2.4 - Sampling Plans In principle, according to AS9100 Rev. C, you could even have an acceptance criteria other than C=0, if the product is noncritical. Looking at the table available here , I think that, in most cases, you could justify an AQL of 0.01%, but not an AQL of 10%.
We sell multiple parts to many different customers and use a C=0 sampling plan to inspect. One of our customers has asked us to use ANSI/ASQC Z1.4 General inspection Level II, Single Sampling, to inspect their parts. Rather than re-writing my internal procedures to accomodate this one...
For higher qty parts, say it is 100, we reference our AQL table to find out the qty of parts we should sampling if all sampling passed, we accept them all, if 1 sampling failed, we do 100% inspection for the whole 100 parts. Honestly, I have no idea how to find a table that would fit in our QSP, inspection plan, etc.
When using a C=0 sampling plan, @ target AQL, would you follow the normal sample plan but instead of utilizing the tables acceptance/rejection criteria to just use accept on failure at that sample? For example, for a sample letter G @ AQL 1.5 for single normal inspection the table would return a sample size of 32, with AC/RE of 1/2 respectively.
C=0 is the norm in aerospace supplies since, for aerospace applications, no lot sould be accepted with known defects. From AS9100 8.2.4: "... [font=Arial,BoldItalic]When the organization uses sampling inspection as a means of product acceptance, the plan shall be statistically valid and appropriate for use.
We use the C=0 Sampling plans at AQL %1.0 for in-process inspection. So for a lot size of 50000, the number of samples to be inspected is 74. Since 50000 is a large quantity and because we don't have enough confidence in our process, what we do is break that purchase order of 50000 into 10 lots, which is 5000 per lot.