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.
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If only a few articles in an inspection lot are nonconforming, the sample probably will indicate that the lot is acceptable; but there is a small probability that the sample will indicate that the lot is unacceptable.
This may be done by placing the units in racks or trays where the positions in the racks are numbered. You may experience issues viewing this site in Internet Explorer 9, 10 or One of these Table satm 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.
ASTM B – 90() Standard Test Method of Variables Sampling of Metallic and Inorganic Coatings
Often in such cases test specimens are coated along with the articles and are used to represent them in the destructive tests. Learn more about the cookies we use and how to change your settings. There may be instances in which tighter or looser plans or ones that atm more discriminating are desired.
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Variables plans are applicable when a test yields a numerical value for a characteristic, when the specification asym a numerical limit on the characteristic, and when certain statistical criteria are met. This last plan utilizes smaller samples and so reduces the cost of inspection but with a sacrice in the ability to distinguish between acceptable and unacceptable lots.
Screening of rejected aatm will substantially increase the cost of inspection if the incoming lots are much worse than AQL quality.
The same sampling plan that was used when the lot was rst inspected shall be used for the b02 of the screened lot. Last previous edition approved in as B — 88 They may be replaced with conforming articles. Formation of Inspection Lot 7. Therefore, basic to any sampling inspection plan is the willingness of the buyer to accept lots that contain some nonconforming articles.
ASTM B – 88() Standard Test Method for Attribute Sampling of Metallic and Inorganic Coatings
There may be cases in which destruction of even these smaller quantities is undesirable. An alternative is rectifying inspection in which rejected lots are screened and used. If one or more of these conditions are not met, a variables plan cannot be used. A table of random numbers Table A1. If only a few articles in an inspection lot are nonconforming, the chances are that the sample will indicate that the lot is acceptable; but there is a small chance that the sample will indicate that the lot is unacceptable.
When incoming lots are of a poor quality level, the average quality of a series of accepted lots will again be good because many of the incoming lots will be rejected and upgraded. ASTM B rp Take the rst two digits in each group of ve digits.
The possibility exists that some of the uninspected articles are nonconforming. For example, if a sample of 50 articles drawn in accordance with Table 2 is found to contain two defectives with respect to thickness and a third one with respect to appearance, the inspection lot is acceptable because although three articles were defective no more than two, the acceptance number, were defective with respect to a single requirement. The resubmitted lot shall be inspected only for the characteristics for which it was rejected.
These are explained in Test Method B Variables plans are applicable when a test yields a numerical value for a characteristic, when the specication imposes a numerical limit on the characteristic, and when certain statistical criteria are met.
ASTM B602 – 88(2016)
The articles are numbered 1 through b60 Screening is to be used only when required by the purchaser. The larger the sample, the smaller this risk but the larger the cost of inspection.
Additional plans that may serve these needs are given in Guide B The larger the proportion of nonconforming articles in an inspection lot, the more likely it will be that the sample will indicate that the lot is unacceptable.