Clothing-manufacturing process control system

Foreign contamination is typically first discovered by quality control checks of the finished product or by the loss of the web for film processes. If a melt filtration system is installed downstream of the extruder, the larger size particles will be collected. After the contaminants are collected they must be analyzed for composition. Some types of contaminants are easily identified using a microscope or hand lens and include paper and cloth fibers, dirt, and metal fragments. Other contaminants such as gels or foreign resins are not as easily identified, and their identification often requires advanced analytical procedures. Many resin manufacturers offer these types of services to their customers. After the contaminant is identified, the source must be determined and then eliminated. Elimination of the source can be simple for common contaminants but can be a challenge for contaminants that exist at a very low level. 

Membrane processes are used to filter liquids. Instead of conventional filter materials (e.g. filter cloth, filter candles,) microporous membranes are employed with molecular size pores. First the industry had to learn how to manufacture membranes with controlled pore sizes. To optimise the filtration capacities specific filter structures had to be designed in which the liquid followed well defined flow patterns on one side of the membrane. Many different systems were developed for the varied applications, all having their advantages and also disadvantages, i.e. plate modules, tubular modules, spiral wound membranes, etc. Research and development in this field is far from being exhausted. Today membrane systems are available which are sufficiently resistant to chemical, mechanical and thermal stress. They are produced from plastic... 

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