Defective batches, reworking

If a product defect is discovered or suspected in a batch, consideration should be given to checking other batches in order to determine whether they are also affected. In particular, other batches which may contain reworks of the defective batch should be investigated. 

Preparation is usually the highest volume single process in a mill thus economics and pollution control greatly favor continuous rather than batch preparation processes [53]. Preparation is also critical to everything that happens later in the mill so the quality of preparation influences the overall quality of work. Latent defects introduced during preparation cause all manner of reworks, off-quality and other problems [54],... 

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