Measurement and Control Technology

For reasons of rationalization and safety modern chemical plants are automated to such an extent that they can be operated with a minimum of personnel. Today an automated plant, regardless of its size, requires a permanent staff consisting of only five shift workers  

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Coils, rewind rollers for radio and videocassettes, stereo cassette parts, tape decks... Precision parts for measurement and control technology. .. 

The selection of the right crystal holder thus plays an important role in all measurements with quartz oscillators. Various crystal holder designs are recommended for the different applications with or without shutter, bakeable for UHV, double crystal holder or crystal six as well as special versions for sputter applications. In addition to these important and more mechanical aspects, the advances in measuring and control technology and equipment features will be discussed in the follovi/ing. 

The necessary basic knowledge is provided in Chapter 2 The Chemical Production Plant and its Components. It deals vhth important subdisciplines of technical chemistry such as catalysis, chemical reaction engineering, separation processes, hydrodynamics, materials and energy logistics, measurement and control technology, plant safety, and materials selection. Thus, it acts as a concise textbook vhthin the book that saves the reader from consulting other works when such information is required. A comprehensive appendix (mathematical formulas, conversion factors, thermodynamic data, material data, regulations, etc.) is also provided. 

To ensure safety, a series of additional measures was required e.g., a largely flangeless construction and reduced-pressure mode of operation of the waste-gas system to avoid leaks installation of a process measuring and control technology with emphasis on safety and construction of an additional exhaustion system on the spinning machines for manual operating procedures. 

Figures 4.2 (a) and (b) show the sequence of the procedure, indicating the points where decisions governing step-by-step action are made. Depending on plant definition, in simple cases a component-oriented analysis may suffice, one which is complete once the determination is made whether requirements specified for components and their design correspond. In many instances the analysis used will be the one which takes into account the materials employed, process parameters, and measuring and control technology. This analysis is indicated when new technical processes are used, when particularly complex interactions are considered, when a higher risk potential exists in the plant, or when economic reasons favor such a course. In a subsequent step the analysis can be in-depth, to the point of the determination of the logic system structure. This will be necessary when particularly detailed results are required or when a transition to a quantitative analysis must be created. Quantitative analysis presumes an adequate data base.

Piping and Instrumentation Symbols Used in Flow Schemes (Table 6) Symbols Used in Measuring and Control Technology... 

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