Process control materials manufacturing

In-process quality control is the control exercised over starting materials and intermediates. Its importance stems from the opportunities that it provides for the examination of a product at the stages in its manufacture at which testing is most likely to provide the most meaningful information. The WHO Requirements and national authorities stipulate many in-process controls but manufacturers often perform tests in excess of those stipulated, especially sterility tests (Chapter 23) as, by so doing, they obtain assurance that production is proceeding normally and that the final product is likely to be satisfactory. Examples of in-process control abound but three of different types should suffice. 

As shown in Tables 6-8 the Indian GMP regulations consists of eight parts I, IA, IB, IC, ID, IE, IF, and II. Part I covers the general requirements of GMP. It is divided into 29 chapters, which deal with the requirements for personnel, premises, equipment, sanitation, production and process controls, materials, documentation, quality management, validation, reserve samples, recalls, complaints, and self-inspection. Parts IA to IE cover specific requirements for the manufacture of different dosage forms regarding premises, equipment, and methods. Part IA deals with the require-... 

Lawrence, J. M., Sozer, E. M., Stadtfeld, H., Simacek, R, Estrada, G., Don, R. and Advani, S. G., Use of sensors and simulations for process control to manufacture a feature based composite with resin transfer molding process . In Proceedings of the Society for the Advancement of the Material and Process Engineering (SAMPE), Long Beach, CA, 2000, pp. 146-155. 

Manufacturing, analytical, and quaUty control procedures are thus estabhshed. Specifications for taw and in-process materials, as well as for final products per USP/NF and in-house standards are also determined. Process and formula vaUdation assures that each technological procedure in manufacture accomplishes its purpose most efficiently, eg, blending times for powdered mixtures in tableting, and that each formula ingredient is present in optimal concentrations (12). Thus, it serves to ensure process control (qv), reproducibiUty, and content uniformity. 

The processes employed in manufacturing a ceramic are defined and controlled to produce a product with properties suited to a specific appHcation. Processing—microstmcture—property relationships are deterrnined by characterizing the ceramic raw materials, mixes, and the formed ceramic body intermittently during processing and after final thermal consoHdation. It is possible to modify and optimize processes to optimize properties and to identify and correct processing deficiencies when less than optimal properties are obtained. Examples of some process—microstmcture—property relations in advanced ceramics are outlined in Figure 4. 

Shear strength is measured via a simple single overlap shear specimen of standard dimensions (Fig. 9). In contrast to its simple appearance, the forces in a thin-adherend shear specimen can be quite complex due to the inherent offset loading of the specimen and subsequent bending in the substrates. The single overlap shear test is anything but a pure shear test, but the configuration is easy to manufacture, simple to test and is firmly entrenched in the industry as a primary examination technique for materials qualifications, inspection and process control. 

The purpose for which the analytical data are required may perhaps be related to process control and quality control. In such circumstances the objective is checking that raw materials and finished products conform to specification, and it may also be concerned with monitoring various stages in a manufacturing process. For this kind of determination methods must be employed which are quick and which can be readily adapted for routine work in this area instrumental methods have an important role to play, and in certain cases may lend themselves to automation. On the other hand, the problem may be one which requires detailed consideration and which may be regarded as being more in the nature of a research topic. 

With the passing of time and looking ahead these material and equipment variabilities continually are reduced due to improvement in their manufacturing and process control... 

Sec. 820.70 Production and process controls - Address production procedures and process controls, changes to the process, environmental controls, clothing and hygiene of personnel, prevention of contamination, suitability and layout of buildings, equipment qualification, maintenance, periodic inspection, and adjustment, removal of unwanted manufacturing materials from devices and automated (computer controlled) processes... 

Quality control tests or improvement of existing processes. Raw materials from various sources can be used in the manufacture of fine chemicals and pharmaceuticals. The raw materials can contain different impurities at various concentrations. Therefore, before the raw material is purchased and used in a full-scale batch its quality should be tested in a small-scale reactor. Existing full-scale procedures are subject to continuous modifications for troubleshooting and for improving process performance. Laboratory reactors used for tests of these two kinds are usually down-scaled reactors or reactors being a part of the full scale-reactor. 

Many materials are complex mixtures of multiple molecular species and components and each component can be in multiple chemical or physical states. Realtime determination of the components and their properties is important for the understanding and control of the manufacturing processes. This paper reviews a recently developed technique of 2D NMR of diffusion and relaxation and its application to identify components of materials. This technique may have further applications for the study of biological systems and in industrial process control and quality assurance. 

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