This standard is issued under the fixed designation B; the number 1 This test method is under the jurisdiction of ASTM Committee B08 on Metallic. ASTM B_机械/仪表_工程科技_专业资料。 Designation: B – 88 ( Reapproved ) Standard Test Method for Attribute Sampling. Purchase your copy of ASTM B – 88() as a PDF download or hard copy directly from the official BSI Shop. All BSI British Standards.
|Published (Last):||28 January 2004|
|PDF File Size:||7.43 Mb|
|ePub File Size:||8.54 Mb|
|Price:||Free* [*Free Regsitration Required]|
The number is compared to a maximum allowable. The permission to use test specimens and the requirements covering them and their use should be set forth in the applicable coating specication, purchase order, or other governing document.
If this number equals or exceeds the specified minimum, atsm inspection lot conforms to the requirements. If the test method is destructive, the sample size shall be that directed in 8. The specific plans selected are identified in B062 1- 3 of this test method.
ASTM B602 – 88(2016)
All other items are then drawn at a constant interval following the rst item. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend.
If every article in an inspection lot conforms to its requirements, every article in the sample will conform also. Also, Guide B describes wstm nature of attribute sampling plans and the several factors that must be considered in the selection of a sampling plan.
ASTM B – 88() Standard Test Method for Attribute Sampling of Metallic and Inorganic Coatings
Active view current version of standard. It is also necessary that the variation of the characteristic from article to article in a production lot be normally distributed see Appendix X2. The correct values are obtained by multiplying the tabulated values by: If it is less, the lot does not conform. NOTE 2—The nature of a destructive test can be such that the tested article can be reclaimed, for example by stripping and reapplying the coating.
The LQL is b6022 quality level that is considered to be barely tolerable. If the test method to be used is nondestructive, the sample size shall be that sstm in 8.
The specific plans selected are identified in Tables of this test method. There may be instances in which tighter or looser plans or ones that are more discriminating are desired. If the purchaser does not specify the level, Level II shall be used.
One of these Table 2 is considered to be standard and is the one that is followed unless the user of this method species either a higher quality level Table 1 or a lower one Table 3.
This standard does not contain the Military Standard’s requirement for tightened inspection when the quality history of a supplier is unsatisfactory.
When the incoming lots are of a good quality level, the average quality level of a series of lots will be even better when the rejected lots are screened and resubmitted. These are explained in Test Method B It is the n602 condition that can occur under rectifying inspection.
For b620 reason, there are no AQL, etc. The possibility exists that some of the uninspected articles are nonconforming. Bias can be avoided by numbering the articles, randomly selecting a group of numbers equal to the sample size, and inspecting the articles with the selected numbers. If the units have serial numbers, the serial numbers can be used.
Through the use of sampling plans, the risk of error is known and controlled.
If the sample is consistently a signicant part of the lot, the correct AOQL will be smaller than the tabulated value. The tables give the AOQL for each plan. At intermediate quality levels of incoming lots, the average quality level of a series of accepted lots will again be improved, but it will not be improved as much as in either of the above cases; and there will be an intermediate quality level where the degree of improvement is the least.
A number in parentheses indicates the year of last reapproval. Such lots will always be accepted. Screening is to be used only when required by the purchaser.
Sampling plans based on inspection by variables are given in Test Method B The AQL is the quality level that is considered to be acceptable. Screening of rejected lots will substantially increase the cost of inspection if the incoming lots are much worse than AQL quality. A random number from 1 to 24 is selected either from a table see A1.
The correct values are obtained by multiplying the tabulated values by the following equation: