Industrial experience

Although the present Good Workmanship approach actually gives conventional NDT methods the credit they deserve (their capabilities are well-used), there should nevertheless be a certainty beyond reasonable doubt that an accepted weld is fit for service. Many years of industrial experience have demonstrated that this certainty statistically exists. We are not doing things totally wrong. 

Industrial Experience While Pursuing the Elusive Cations of Carbon... 

O. L. Davies, The Design andMnalysis of Industrial Experiments, Longman, New York, 1978. 

Tb allium, which does not occur naturaHy in normal tissue, is not essential to mammals but does accumulate in the human body. Levels as low as 0.5 mg/100 g of tissue suggest thallium intoxication. Based on industrial experience, 0.10 mg /m of thallium in air is considered safe for a 40-h work week (37). The lethal dose for humans is not definitely known, but 1 g of absorbed thallium is considered sufficient to kHl an adult and 10 mg/kg body weight has been fatal to children. In severe cases of poisoning, death does not occur earlier than 8—10 d but most frequently in 10—12 d. Tb allium excretion is slow and prolonged. For example, tb allium is present in the feces 35 d after exposure and persists in the urine for up to three months. 

The most serious ha2ard of repeated exposure to chloroform inhalation is injury to the Hver and kidneys. Evidence indicates that in humans, repeated exposure to atmospheric concentrations well below the odor threshold may cause such injury. Industrial experience has shown that daily exposure to concentrations below 100 ppm may result in a variety of nervous system and alimentary tract symptoms, in the absence of demonstrable evidence of injury (39). Injury to the Hver is similar to but somewhat less severe than that caused by carbon tetrachloride. Kidney injury is usually associated with but less severe than Hver injury. 

When a reaction has many participants, which may be the case even of apparently simple processes like pyrolysis of ethane or synthesis of methanol, a factorial or other experimental design can be made and the data subjected to a re.spon.se. suiface analysis (Davies, Design and Analysis of Industrial Experiments, Oliver Boyd, 1954). A quadratic of this type for the variables X, Xo, and X3 is... 

When heavier refractories are required because of operating conditions, insulating brick is installed next to the shell and firebrick is installed to protect the insulating brick. Industrial experience in many fields of application has demonstrated that such a hning will success-billy withstand the abrasive conditions for many years without replacement. Most serious refractory wear occurs with coarse particles at high gas velocities and is usually most pronounced near the operating level of the fluidized bed. 

AICliE and CCPS would also like to express their appreciation to Arthur D. Little, Inc. for their contribution in preparing this book for publication. It is the collective industrial experience and know-how of the subcommittee members plus the experience and expertise of Arthur D. Little, Inc. that makes this book especially valuable to the process and design engineer. Dr. Georges A. Melhem was the Director-in-Charge of this project, for Arthur D. Little, Inc. Dr. Sanjeev Mohindra of Arthur D. Little, Inc. was the author and Christina Hourican handled the somewhat complex word processing for this project. 

The TLVs, as recommended and published by the ACGIH, refer to concentrations of airborne contaminants or levels of physical agents, and represent the conditions to which it is believed nearly all workers may be repeatedly exposed day after day without adverse effects. TLVs are based on the results of animal experiments, limited human experiments, some industrial experience and, when possible, a combination of all three. 

The frequency of an initiating event is usually based on industrial experience. If the process is new or rare, it may be estimated by a system model of the process steps (e.g., a fault tree) and using data from similar experience to give the probability of failure of the steps. Either of these estimates should consider the possibility of mitigating actions to prevent the hazard from having detrimental effects. 

Literature from industrial experience, especially individual case reports showing relationship between exposure to a chemical agent and specific adverse effects... 

Davies, O.L., 1979. The Design and Analysis of Industrial Experiments, 2nd edition. London Longman Group Limited. 

Mosleh, Kazarians, and Gekler obtained a Bayesian estimate of the failure rate, Z, of a coolant recycle pump in llie hazard/risk study of a chemical plant. The estimate was based on evidence of no failures in 10 years of operation. Nuclear industry experience with pumps of similar types was used to establish tire prior distribution of Z. Tliis experience indicated tliat tire 5 and 95 percentiles of lire failure rate distribution developed for tliis category were 2.0 x 10" per hour (about one failure per 57 years of operation) and 98.3 x 10 per hour (about one failure per year). Extensive experience in other industries suggested the use of a log-nonnal distribution witli tlie 5 and 95 percentile values as llie prior distribution of Z, tlie failure rate of the coolant recycle pump. 

Rules of thumb that have developed out of many years of industrial experience relating to downcomer sizing include ... 

Myers found only a slight decrease in efficiency with an increase in hole size. Industrial experience indicates that large holes of 14-in. and %-in. can be designed to operate as efficiently as a small hole, say Xe-in. 

Figures 9-21F and 21G (for Norton s IMTP packing only) can be up to 20% higher than industrial experience for the same Cj values at a flow parameter (FP) of 0.01 [82]. At an absolute colunrn pressure of 10 mm Hg or less, the pressure drop actual can be up to 30% lower than that read from the Figure 9-21F at the FP of 0.01 and the same Cg value [82]. The conclusion is that the generalized correlation, Figures 9-2IF and -21G always give a conservative design AP at operating pressures less than 70 mm Hg abs. Several other factors must be considered, such as variability of gas and liquid rates and densities or specific volumes.

Short and Brown in reference 172 found no net penalty against the single tube coefficient in a single row 20 tubes high. Belh concurs that this is home out in industrial experience, and current design practice is to assume that the average coefficient for the entire tube bank is the same as for a single tube. ... 

FPN No. 1) It is important that the authority having Jurisdiction be familiar with recorded industrial experience as well as with standards of the National Fire Protection Association, the American Petroleum Institute, and the Instrument Society of America that may be of use in the classification of various locations, the determination of adequate ventilation, and the protection against static electricity and lightning hazards. 

Recent industrial experience for alloys in waste incineration plants has indicated the superiority of nickel-base alloys compared with iron-base and iron-containing alloys as would be expected from the previous discussion of the volatility of chlorides. Nickel-base alloys with no addition of iron and relatively high chromium contents have significantly improved performance in these applications (see Tables 7.33 and 7.34.) . 

The most efficient washing of the hydroxide was achieved applying a three-step process using an ammonium carbonate solution as the first step, followed by an ammonia solution, and water as the final step. This washing process brings about a ten-fold reduction in the concentration of fluorine compared with laboratory and industrial experience, in which a 2-4 fold reduction in the fluorine content of tantalum or niobium hydroxides following a one-step washing process was obtained. 

Different procedures for the precipitation, washing and thermal treatment of hydroxides result in different fluorine contamination levels in the final products - tantalum and niobium oxides. Laboratory and industrial experience confirms some correlation between the initial concentration of fluorine in the dried hydroxides and the fluorine content in the final oxides obtained after appropriate thermal treatment. For instance, it is reported in [499] that if the initial concentration of fluorine in niobium hydroxide equals A%, then the fluorine content in the final niobium oxide can be estimated according to the thermal treatment temperature as follows ... 

Potassium heptafluorotantalate, K2TaF7, precipitates in the form of transparent needles. The precipitated particles must not be too fine, since fine powder usually promotes co-precipitation and adsorption of some impurities from the solution. Even niobium can be adsorbed by the surface of K2TaF7 developed during precipitation, as shown by Herak et al. [535]. On the other hand, the precipitation of large K-salt crystals should not be strived for either. Laboratory and industrial experience indicates that excessively large crystals usually contain small drops of solution trapped within the crystals. This occluded solution can remain inside of the crystal until drying and will certainly lead the hydrolysis of the material. 

Similarly, although the benefit of good industrial experience cannot be underestimated, service company representatives who lack appropriate technical qualification will always be limited in their ability to fully interpret analytical results and trends and provide authoritative recommendations. 

The authors wish to thank CITRIMUSA (Murcia, Spain) for their collaboration in the industrial experiments, and Novo Nordisk Ferment Ltd. (Dittingen, Switzerland) for their support in enzymatic preparation. 

The general assessment indicates that the pharmaceutical industry experiences problems with transparency of dmg registration in two out of the 10 countries— Cypms and Uganda. The main problems cited involve communication between the DRA and the industry regarding clarity of procedures and adequacy of official explanations for the rejection of an application. In Cypms, the Dmg Council also raised issues concerning the fairness of treatment of foreign versus domestic industry, and the arbitration of contradictory quality analysis results provided by different laboratories, both belonging to the Dmg Council. 

So far, no scientific extrapolation has been published on the cost savings for the chemical industry when using micro reactors. Industrial experience is also not known at least, it has not been communicated. Thus, one is boimd to rely on expert opinions given in the press and trade press. Mostly these come from suppliers of the technology, aiming to convince industry of the benefits of their systems, by prognosis of a return on investment. Considering the pharmaceutical R D efforts of the order of US 50 billion worldwide, CPC/Mainz sees a potential for an increase in profit of more than US 15 billion if micro reactors are implemented consequently [246]. 

The views expressed here are my own, and they are based upon 17 years of industrial experience, 12 of which were in research management, so they should prove representative, as they are driven by a common set of pressures present in the current industrial climate. The three basic questions that I address are... 

The third chapter deals with leuco derivatives of the oxazine, thiazine, and phenazine dyes, and is written by Tran Van Thien, who has had many years experience in photoimaging at the 3M Research Center, Harlow. His industrial experience in leuco dyes has enabled him to produce a collation of material impossible to find elsewhere in a single review, and again recipes for the synthesis of representative examples abound. Consideration is also given to the numerous applications of these molecules in thermal and photo-imaging systems. 

It should be emphasized that qualitative consequence screening should only remove from further consideration those buildings where there is significant industry experience to support the assessment. In Example 5 cited above, a long and successful operating history exists to support the... 

Both industry experience and research work indicate that postweld heat treatment (PWHT) of chromium-molybdenum steels in hydrogen service improves resistance to high temperature hydrogen attack. The PWHT stabilizes alloy carbides. This reduces the amount of carbon available to combine with hydrogen, thus improving high temperature hydrogen attack resistance. 

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