High reliability

Our experiences with the software developed within the ANDES project have shown that CBR is a helpful methodology for use in the interpretation of NDT data from field inspections. Because CBR systems can adapt to new situations they can cope with inspection of varying constructions in varying conditions. However, because CBR systems learn from classifications made by the operator this means that they will not be very useful for completely automatic interpretation. Fortunately, most of the NDT inspection requires the presence of an operator because of the required high reliability. 

Fligh-tech ceramics withstand great mechanical stresses even thin structures and sharp edges are feasible with high reliability. This allows connecting the HT cables reliably to the ceramic part of the tubes directly. Many available resin systems bond easily to ceramics. 

High reliability. Many things can go wrong with a steam tracing system but, very few of the potential problems lead to a heat tracing failure. Steam traps fail, but they usually fail in the open position. 

Description The spiral-plate heat exchanger (SHE) may be one exchanger selec ted primarily on its virtues and not on its initial cost. SHEs offer high reliability and on-line performance in many severely fouling seiwices such as slurries. 

Alternating-Current Squirrel-Cage Induction Motors These motors are by far the most common constant-speed drives. They are relatively simple in design and therefore both low in cost and highly reliable. Representative prices are shown in Fig. 29-1 for various speeds and horsepowers. 

Design eriteria must inelude high reliability and availability. 

The foregoing demonstrates that modern digital devices offer highly reliable, state-of-die-art microprocessor technology that controls turbomachinery strings, monitors operating data, stores data for subsequent evaluation, communicates to odier systems, and can expand with future technologies. 

Component reliability will vary as a function of the power of a dimensional variable in a stress function. Powers of dimensional variables greater than unity magnify the effect. For example, the equation for the polar moment of area for a circular shaft varies as the fourth power of the diameter. Other similar cases liable to dimensional variation effects include the radius of gyration, cross-sectional area and moment of inertia properties. Such variations affect stability, deflection, strains and angular twists as well as stresses levels (Haugen, 1980). It can be seen that variations in tolerance may be of importance for critical components which need to be designed to a high reliability (Bury, 1974). 

Meeker, W. Q. and Hamada, M. 1995 Statistical Tools for the Rapid Development and Evaluation of High Reliability Products. IEEE Transactions on Reliability, 44(2), 187-198. 

It is hoped that this material will give the reader an appreciation for the many different factors that interact to cause a compressor installation to be successful or a failure. It is sincerely hoped that when all the various aspects are critically addressed that any proposed installation will achieve the high reliability that a user may expect. 

That is, highly important but highly reliable passive components have a high Birnbaum Importance. To overcome this problem. 

Risk Reduction Factors Coutrol/ rator responses. Alarms, Control system response. Manual anti automatic ESD, Fire/gas detection system Sa/ety System Responses Relief valves. Depressurization system. Isolation systems, High reliability trips. Back-up systems... 

High reliability items and single-point failure items... 

The requirements within the product specification need to be expressed in terms that can be verified. Hence you should avoid subjective terms such as good quality components , high reliability , commercial standard parts , etc. as these requirements are not sufficiently definitive to be verified in a consistent manner. (See the later section on Design acceptance criteria and Part 2 Chapter 2 on Clarifying standards of acceptabili-fy-)... 

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