Inspection Standards

Sampling standard

Quality inspection standards (AQL)

Ningbo Mini Tree (NMT) use the default ANSI/ ASQC Z1.4 as the quality acceptance criteria, sampling inspection of batches of products by using this method, the decision of the batches of the product is qualified, no need to test on the batch of products each of them, the sampling acceptance criteria are widely used all over the world.

Inspection sampling

Inspection sampling is used to determine whether to accept or reject a batch of goods. First of all, from a randomly selectedsample of a batch of goods, and to test the selected samples, and then accept or reject the batch of goods is determined according to the results of.

Batch / lot

Batch or batch of products is a collection of many products, its size, type, production conditions and time consistent sampleextraction, in the meantime, to determine the batch / lot whether the products met the acceptance criteria.

General sampling inspection standards

Sampling standard sampling method accurately represents the whole. For a given quantity of batches of products, improve the quality of sampling standard means increasing the sampling number.

Sampling standard general quality is divided into I, II and III level.

Ningbo Mini Tree (NMT) quality sampling standard default to IIlevel. But the specific selected sampling standard grade but alsoaccording to the customer required or authorized to conduct!

The number of samples

On the basis of the number of customer specified level and corresponding AQL standard sample of the actual quantity ofgoods corresponding extracted by.

The quality of the product acceptability criteria and classification of defects

In general, a defect is found in the inspection process is divided into three categories:

- a very serious defect (CRITICAL)

- severe defects (MAJOR)

- a slight defect (MINOR)

Very serious defect

Very serious defect refers to defects may result in personal safetyand health effects to the end user. Or this product completely without corresponding function.

Ningbo Mini Tree (NMT) and acceptance of the quality standardof very serious defect to zero by default.

Serious defect

Serious defects in order not to affect the security situation may cause the defect product availability function reduction orappearance was completely damaged.

Ningbo Mini Tree (NMT) and acceptance of the quality standard of serious flaws in the default value is 1.5. (specific to the customer specified level)

Slight defects

- slight defects will not damage the product normal use or deviate from the relevant standards.

The slight defect, quality standard is a kind of process defects.

Ningbo Mini Tree (NMT) and acceptance of the quality standard of minor defects in the default value is 4. (specific to the customer specified level)

How to determine the number of the sampling number and acceptance?

Assume that the tests were carried out on a batch of a total of 1000 products, on the basis of acceptance quality standard of G-II, the following table shows the sampling number should be 80.According to Critical 0, Major 2.5, Minor 4 quality acceptance standard, this batch of product defects standard acceptable for: the number of defects in a serious of 0, serious defects acceptable quantity is 3 pieces, the slight defect acceptable number of 7. If the randomly selected sample in the absence of serious defects found, serious defects of more than 3 pieces or slight defects in more than 7 pieces, the batch of products are rejected.