Faulty design

It should be made clear that all the rates of rusting in the atmosphere just quoted, relate to average general penetration and take no account of pitting. Serious pitting of steel exposed to atmospheric corrosion is uncomm.on on simple test plates, but it may be necessary to allow for this in some practical cases, where local attack may be occasioned by faulty design and other factors. 

Problems with service experience include obtaining sufficient information on the actual conditions of service, finding that these conditions are much milder than the design conditions, or that the polymer formulation used has now been superseded. Life prediction cannot consider failures caused by poor workmanship, incorrect use or maintenance, or faulty design, particularly of joints, attachments or in the choice of neighbouring materials. Many failures in practice are due to degradation in processing, faulty assembly, or to abuse. 

Experienced incident investigators know that such specific failures are but the immediate causes of an incident, and that underlying each such immediate cause is a management system failure, such as faulty design or inadequate training.. . . ... 

The importance of packaging has already been mentioned in connection with the problem of oxidation. In most cases where a problem arises due to the faulty design of the packaging or the injudicious selection of component materials there is little that the perfumer can do other than to identify the true cause of the problem. 

Over the last 30 years, robotic systems to automate manual laboratory techniques have become available. More recently, robotic systems have evolved that operate unattended and are capable of high-throughput solid dosage-form analysis with an accuracy and precision equivalent to their corresponding manual techniques. These systems initially suffered from faulty design, frequent breakdown, poor user interface, and complex programming requirements, but to a great extent, these faults have been overcome. 

Failure analysis can be related to potential crack growth behavior to prevent fracture. Fracture is a crack-dominated failure mode. For fracture to occur, a crack must somehow be created, then initiate, and finally propagates. The prevention of any of these events will prevent fracture. Cracks can be considered elastic discontinuities that can come from a variety of sources such as internal voids or dirt, and/or surface scratch, embrittlement, or weld line. Cracks can be consequences of faulty design, poor processing, and/or poor handling of raw material, assuming material arrived clean (Figure 7.6). 

Since the mode of action and the dependence on environmental factors may be very different for different chromosome-breaking chemicals, there is always a risk of a possible chromosome-breaking effect being undetected as a result of faulty design of the experiment. There are chemicals which in plant materials act mainly, or exclusively, during late interphase and mitosis (see caffeine, section V, D see also Kihlman, 1966), whereas in other cases there has to be a period of DNA synthesis between treatment and fixation if any aberrations are to be found in mitotic cells. Such a dependence on DNA synthesis has been observed after treatments with alkylating agents (Evans and Scott, 1969) and maleic hydrazide (Evans and Scott, 1964 ... 

Modulation Noise. This noise is generated by scintillations or system modulations, and it is directly proportional to the signal level. It can be caused by refractive index fluctuations in very long-path atmospheric measurements and in astronomical measurements, or by faulty design in laboratory instrumentation. 

Ultrasonic monitoring shows thin walls for pipes, internals or vessels faulty ultrasonic instrument/[corrosion] /faulty design. Failure of supports, internals, vessels" [corrosion] /faulty design/unexpected stress or load. 

Knock out pots "Poor separation" [foamtng] /insufficient residence time/feed and exit nozzles at wrong location/faulty design. 

Entrained liquid in overhead gas sensor error/[entrainment GL]. Incomplete separation of oil from water faulty design of separator/residence time of liquid phases too short/liquid velocity in the decant phases too fast/Marangoni instabil-ities/liquid feed velocity too fast/poor distribution of liquid feeds/faulty location of exit nozzles for liquid phases/overflow baffle corroded and failure/interface level at the wrong location/faulty control of interface/no vortex breaker at water and heavy oil exit nozzles/liquid exit velocities too high/ emulsification]. ... 

Settlers Floe or particulates do not settle size different from design/density different from design/unanticipated turbulence or back eddies/liquid residence time too short/feed flowrate > design/incorrect design of inlet/faulty design of solids removal. Supernatant not clear [floe or particulates do not settle] /faulty design of overflow weirs/short circuiting. 

Poor catalyst stripping] insufHcient steam stripping flowrate/faulty flow controller on steam flow/faulty design of stripper/reactor temperature too low/faulty contacting between steam and catalyst/circulation rate too high/coarse particles. 

Impeller not in the continuous phase] phase ratio differs from design/faulty design/wrong direction of mass transfer. 

As noted in the introduction, it is important to identiiy the causes of fracture so that manufacturers, clinicians, and laboratory technicians can minimize the incidence of breakage. Identification of the mechanisms of fracture can help researchers can develop relevant testing procedures. Table 1 shows that there were multiple causes of failure including faulty design of the restoration, faulty preparation, or damage from clinician handhng or adjustments. There were no fracture mirrors, so all the fractures occurred at relatively low stress levels. 

For the above reasons, and as a faulty design of system components may lead to a reduced availability of a system, entail unwanted repair costs, or may lead to failures with consequences that can be detrimental or even catastrophic, it is important to take into account detection, diagnosis of possible abnormal system behaviour and... 

Beyond these causes, wear and tear during normal system operation, human operator errors, postponed maintenance, or a faulty design of a system component, or errors in the assembly of system components from different engineering domains may result in gradually or suddenly occurring faults with possibly disastrous consequences. 

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