Sampling and Lot Testing
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Description: Sampling and lot testing help ensure the overall quality of a batch of incoming materials by testing a small subset and using statistical analysis to infer the quality of the entire lot. This process is crucial for ensuring the consistency and reliability of the materials.
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Process Detail:
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Define Sampling Plan: Determine the appropriate sampling plan based on the expected quality of the materials. Commonly used standards like AQL (Acceptable Quality Level) will define how many units should be tested from a larger lot. For example, you may test 5% of a shipment or select a fixed number of units for testing.
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Perform Lot Tests: Perform functional, mechanical, or electrical tests on the selected samples. For instance, if testing ICs, you might test their input/output properties and voltage levels, while for capacitors, you might check their capacitance and ESR (equivalent series resistance).
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Analyze Results: If the results from the sample pass the required specifications, the whole lot is considered acceptable. If any samples fail, the entire lot should be rejected or further investigated for possible defects. Detailed records of test results should be maintained for traceability.
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Statistical Analysis: Based on the testing results, perform a statistical analysis to determine if the lot meets the required quality standards. This step helps in making data-driven decisions about whether to accept or reject the materials.
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