Proven engineering practices

Wherever possible, stractmes, systems and components important to safety shall be designed according to the latest or currently applicable approved standards shall be of a design proven in previous equivalent applications and shall be selected to be consistent with the plant reliability goals necessary for safety. Where codes and standards are used as design rales, they shall be identified and evalirated to determine their applicability, adequacy and sufficiency and shall be supplemerrted or modified as necessary to ensure that the final quality is commensirrate with the necessary safety function. 

Where an improven design or feature is introduced or there is a departure from an established engineering practice, safety shall be demonstrated to be adeqrrate by appropriate supporting research programmes, or by examination of operational experience from other relevant appUcations. The developmerrt shall also be adeqrrately tested before being bronght into service and shall be monitored in service, to verily that the expected behavionr is achieved. 

In the selection of eqiripment, consideration shall be given to both spirrious operation and unsafe failttre modes (e.g. failure to trip when necessary). Where failure of a structure, system or componerrt has to be expected and accommodated by the design, preference shall be given to eqiripmerrt that exhibits a predictable and revealed mode of failure and facilitates repair or replacemerrt. 

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Proven engineering practices (3.6-3.8) Operational experience and safety research (3.9) Safety assessment (3.10-3.12)... 

The requirements for management of safety (Section 3 in Ref [1]) address the issues which relate to proven engineering practice, operating experience and safety research. 

The basis for the safety assessment shall be data derived from the safety analysis, previous operational experience, results of supporting research and proven engineering practice. 

General technical principles Proven engineering practices Quality assurance Human factors Safety assessment and verification Radiation protection Operating experience and safety research ... 

Criterion 9. Proven engineering practices Scope to address materials selection, fabrication, installation, examination, and testing. 

Rules of thumb, also known as heuristics, are statements of known facts. The word heuristics is derived from Greek, to discover or to invent, so these rules are known or discovered through use and practice but may not be able to be theoretically proven. In practice, they work and are most safely applied by engineers who are familiar with the topics. Such rules are of value for approximate design and preliminary cost estimation, and should provide even the inexperienced engineer with perspective and whereby the reasonableness of detailed and computer-aided design can be appraised quickly, especially on short notice, such as a conference. 

The SVBR-75/100 project has been devised using a conservative approach. This presumes to use the primary and secondary circuit design and operation parameters already proven in practice, the mastered technologies of fuel and structural materials, and those principal engineering solutions regarding the equipment components and the reactor scheme that have been verified by operating experience. 

Sound design engineering practices including proven designs, proper materials selection, and appropriate manufacturing methods... 

Simplified models that do not make a priori assumptions about one or more dominant resistances are often of the 1-D macrohomogeneous type. The 1-D assumption is similar to that in mass transfer-based models. The assumption of macrohomogeneity, based on work by Newman and Tobias [50], has proven useful in battery and fuel cell electrode modelling. It implies that the microstructure of the electrode is homogeneous at the level of the continuum equations governing mass transfer, heat transfer, and current conduction in the electrode (Eqs. (l)-(7) and (33)-(37)). This type of model can exploit solutions available in chemical reaction engineering practice and has been elaborated by several researchers in that field [51-55],... 

It should be clear that a complete FMEA approach is not practical for the evaluation of production facility safety systems. This is because (1) the cost of failure is not as great as for nuclear power plants or rockets, for which this technology has proven useful (2) production facility design projects cannot support the engineering cost and lead time associated with such analysis (3) regulatory bodies are not staffed to be able to critically analyze the output of an FMEA for errors in subjective judgment and most importantly, (4) there are similarities to the design of all production facilities that have allowed industry to develop a modified FME.A approach that can satisfy all these objections. 

Plate design, like most engineering design, is a combination theory and practice. The design methods use semi-empirical correlations derived from fundamental research work combined with practical experience obtained from the operation of commercial columns. Proven layouts are used, and the plate dimensions are kept within the range of values known to give satisfactory performance. 

API standards are published to facilitate the broad availability of proven, sound engineering and operating practices. These standards are not intended to obviate the need for applying sound engineering judgment regarding when and where these standards should be utilized. The formulation and publication of API standards is not intended in any way to inhibit anyone from using any other practices. 

To develop an alternative MIEC cathode not only the ex situ properties, e.g., cr, TEC, /), and k, but also the electrocatalytic activity, structural and chemical stability, and Cr-tolerance must be considered. Beyond testing in small SOFC button cells, the viability of new cathode materials must ultimately be proven in large-scale stack cells under practical current and temperature gradients. The issues involved in the development of cathode materials for large-scale stacks are significantly more complex than those in the small button cells briefly reviewed in this chapter. However, this does provide serious challenges as well as opportunities for materials scientists and engineers in the development of commercially viable ITSOFCs. 

The practicality and environmental consequences of many sequestration techniques have not yet proven from an engineering or scientific aspect. Sequestration still requires much research and development before generating large volumes of hydrogen from coal and sequestering the C02 produced. C02 sequestration on a massive scale would need to be permanent to be practical. 

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