scholarly journals A Spreadsheet Program For The Calculation Of Piping Systems And The Selection Of Pumps

2020 ◽  
Author(s):  
Craig W. Somerton
Keyword(s):  
Spreadsheet Program ◽  
Piping Systems ◽  
Selection Of

The TransAlta High-Energy Piping Program—A Five-Year History

2000 ◽  
Vol 123 (1) ◽  
pp. 65-69 ◽  
Author(s):  
Marvin J. Cohn,
Keyword(s):  
Creep Damage ◽  
Analytical Techniques ◽  
High Energy ◽  
Management Plan ◽  
Piping System ◽  
Engineering Consulting ◽  
Piping Systems ◽  
Creep Fatigue ◽  
Sustained Loads ◽  
Selection Of

In 1995, the High-Energy Piping Strategic Management Plan (HEPSMP) was initiated at TransAlta Utilities Corporation (TAU) for the three generating facilities. At that time, it was recognized that several of the piping systems were exhibiting signs of creep relaxation, with some hangers bottomed or topped out online and/or offline. Previous hanger adjustment attempts were not always adequate. The program workscope included: 1) hot and cold piping system walkdowns, 2) selection of high-priority girth weld inspection locations, 3) examination of critical weldments, 4) weld repairs where necessary, 5) adjustments or modifications of malfunctioning steam line hangers, and 6) recommended work for future scheduled outages. Prior to 1996, examination locations were limited to the traditional locations of the terminal points at the boiler and turbine, with reexaminations occurring at arbitrary intervals. Since the terminal points are not necessarily the most highly stressed welds causing service-related creep damage, service damage may not occur first at the pre-1996 examined locations. There was a need to maximize the safety and integrity of these lines by ensuring that the highest risk welds were identified and given the highest priority for examination. An engineering consulting company was selected to prioritize the highest risk weldments for each piping system. This risk-based methodology included the prediction and evaluation of actual sustained loads, thermal expansion loads, operating loads, multiaxial stresses, creep relaxation, and cumulative creep life exhaustion. The technical process included detailed piping system walkdowns and application of advanced analytical techniques to predict and rank creep/fatigue damage for each piping system. TAU has concluded that the program has met its objective of successfully prioritizing inspection locations. The approach has also resulted in reducing the scope and cost of reexaminations. Phases 1 and 2 evaluations and examinations have been completed for all units. Results of some of the important aspects of this program are provided as case history studies.

scholarly journals Biofilms and hygiene on dairy farms and in the dairy industry: sanitation chemical products and their effectiveness on biofilms – a review

2008 ◽  
Vol 26 (No. 5) ◽  
pp. 309-323 ◽  
Author(s):  
H. Vlková ◽  
V. Babák ◽  
R. Seydlová ◽  
I. Pavlík ◽  
J. Schlegelová
Keyword(s):  
Raw Materials ◽  
Dairy Industry ◽  
Dairy Farms ◽  
Physical Parameters ◽  
Model Studies ◽  
Piping Systems ◽  
Specific Contact ◽  
Number Of Microorganisms ◽  
Materials Used ◽  
Selection Of

Microbial biofilms which form on all types of surfaces of technological systems in the dairy industry and on dairy farms adversely affect the quality and safety of final products, i.e. both foodstuffs and raw materials used for their production. The fact that a number of microorganisms are alimentary pathogens, e.g. <I>Staphylococcus aureus</I> or <I>Listeria monocytogenes,</I> makes a serious problem directly affecting human health. Biofilms are usually formed by various species of microorganism, which protect each other against the effects of biocidal (antibacterial) agents and are resistant to these agents. The colonisation of surfaces of the open and closed piping systems, floors, waste, walls and ceilings of the production halls becomes a major problem in the selection of effective sanitation agents for their control. Based on the existing model studies, practical methods for testing the effectiveness of sanitation procedures should be evaluated, including the selection of biocides and comparison of the physical parameters of the sanitation procedures. Testing the effectiveness of the sanitation agents should be performed with the use of standardised tests, which consider microbial, structural, and chemical characteristics of the living microbial communities on specific contact surfaces in the food-processing industry.

Economic Sizing of Steam Piping and Insulation

1979 ◽  
Vol 101 (4) ◽  
pp. 427-433 ◽  
Author(s):  
W. J. Wepfer ◽  
R. A. Gaggioli ◽  
E. F. Obert
Keyword(s):  
Heat Transfer ◽  
Energy Content ◽  
Economic Value ◽  
Operating Costs ◽  
Pipe Diameter ◽  
Simple Method ◽  
Available Energy ◽  
Piping Systems ◽  
Insulation Thickness ◽  
Selection Of

This paper presents a simple method for the optimal economic selection of pipe size and insulation thickness for steam piping systems. The primary operating costs inherent in any such system are consequences of fluid-flow friction and heat transfer losses. Striving to conserve energy, the engineer is motivated to select large pipe diameters and insulation thicknesses. But how large should the pipe diameter be and how much insulation is necessary? The answer is simply to make that investment in piping and insulation which minimizes the sum of the capital and operating costs (friction and heat transfer). Thus it is imperative that the operating expenses be precisely evaluated. The key is the recognition that it is available energy which is the commodity of value—that it is necessary to assign an economic value (cost) to the steam based on its available energy content. Because friction and heat transfer destroy available energy, their respective costs can then be accurately assessed. As an example a bleeder steam line that delivers 55,300 lbm/hr (7 kg/s) at 93.8 psia (0.65 MPa) and 603 F (317 C) to a feedwater heater is analyzed to show the optimal nominal pipe diameter and insulation thickness to be 12 in. (30.48 cm) and 3.5 in. (8.89 cm), respectively.

Twenty Years After the Production of the First Heavy Water Drop in Romania: July 17th, 1988 – July 17th, 2008—Piping Systems

2008 ◽  
Author(s):  
Aurel M. Alessandrescu
Keyword(s):  
Heavy Water ◽  
Water Drop ◽  
Normal Pressure ◽  
Water Application ◽  
Pipe Expansion ◽  
Nominal Pressure ◽  
Piping Systems ◽  
Pipe Joints ◽  
Equipment System ◽  
Selection Of

1. Heavy Water application. 2. Heavy Water technology. 3. Isotope exchange installation- piping systems characterstics. 3.1. Piping systems characteristics: (a) crack-inducing corrosion in wet and gaseous hydrogen sulphide medium. (b) selection of a higher nominal pressure than the normal pressure for pipe classes. (c) minimization of flanged pipe joints. (d) provision of piping systems selfcompensation in case that lenticular pipe expansion loops can not be used. (e) use of spiral-wound gaskets for all the piping systems flanged connections. 3.2. Piping-equipment system interaction. 3.2.1. Severe limitation of the loads in the piping systems-equipments joints. 3.2.2. Use of constant elastic supports to protect the piping systems associated equipment nozzles. 3.3. Bearing range. 4. Today objectives: to extend the predicted service-life of the piping systems. 5. Nomenclature. 6. References.

Power Piping Grade 91 In-Service Cracks

2019 ◽  
Author(s):  
Marvin J. Cohn ◽  
Steve R. Paterson ◽  
Keith Rapkin ◽  
Charles Henley ◽  
Erick Liebl ◽  
...  
Keyword(s):  
Time Dependent ◽  
Piping System ◽  
Material Damage ◽  
Nondestructive Examination ◽  
Commercial Operation ◽  
Piping Systems ◽  
Grade 91 ◽  
Main Steam ◽  
Creep Regime ◽  
Selection Of

Abstract After a power piping system has begun commercial operation, it is recommended that the initial nondestructive examination (NDE) of the welds should be developed and executed to reveal possible fabrication and early service-related material damage. The identified indications and other possible anomalies should be thoroughly documented, evaluated, and dispositioned. Additional early service-related cracks may initiate and propagate several years after the first examination. This paper considers historical early service-related cracks in weldments of power piping systems operating in the creep regime. Factors that dominate these early service-related cracks are discussed in this paper. This paper provides a list of more than 20 historical examples of power piping Grade 91 material macrocracks (partial wall or through-wall) that were not present immediately after construction and propagated substantially in service. Five of the examples are discussed in more detail. The study only includes cases where propagating cracks were confirmed. It does not include examples where NDE reportable indications have not propagated in service to large macrocracks. Due to the time-dependent nature of these girth weld cracks, the results of this study may be used to assist in the selection of Grade 91 reexamination locations after the power piping system (e.g., main steam, hot reheat, high pressure, or intermediate pressure) has been several years in service.

Cognitive gadgets and cognitive priors

2019 ◽  
Vol 42 ◽  
Author(s):  
Gian Domenico Iannetti ◽  
Giorgio Vallortigara
Keyword(s):  
Cognitive Neuroscience ◽  
Selection Of

Abstract Some of the foundations of Heyes’ radical reasoning seem to be based on a fractional selection of available evidence. Using an ethological perspective, we argue against Heyes’ rapid dismissal of innate cognitive instincts. Heyes’ use of fMRI studies of literacy to claim that culture assembles pieces of mental technology seems an example of incorrect reverse inferences and overlap theories pervasive in cognitive neuroscience.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

Measurements of the Cape Astrometric Survey of the Southern Hemisphere

1978 ◽  
Vol 48 ◽  
pp. 515-521
Author(s):  
W. Nicholson
Keyword(s):  
Southern Hemisphere ◽  
Automatic Measuring ◽  
Measuring Machine ◽  
Final Selection ◽  
Selection Of

SummaryA routine has been developed for the processing of the 5820 plates of the survey. The plates are measured on the automatic measuring machine, GALAXY, and the measures are subsequently processed by computer, to edit and then refer them to the SAO catalogue. A start has been made on measuring the plates, but the final selection of stars to be made is still a matter for discussion.

Application of Improved Voltage Compensation in the SEM to Imaging of Organic Materials

1973 ◽  
Vol 31 ◽  
pp. 444-445
Author(s):  
P.J. Killingworth ◽  
M. Warren
Keyword(s):  
Electron Beam ◽  
Organic Materials ◽  
Operating Parameters ◽  
Low Density ◽  
Beam Diameter ◽  
Incident Electron Beam ◽  
Specimen Material ◽  
Voltage Compensation ◽  
Selection Of ◽  
Scanning Electron

Ultimate resolution in the scanning electron microscope is determined not only by the diameter of the incident electron beam, but by interaction of that beam with the specimen material. Generally, while minimum beam diameter diminishes with increasing voltage, due to the reduced effect of aberration component and magnetic interference, the excited volume within the sample increases with electron energy. Thus, for any given material and imaging signal, there is an optimum volt age to achieve best resolution.In the case of organic materials, which are in general of low density and electric ally non-conducting; and may in addition be susceptible to radiation and heat damage, the selection of correct operating parameters is extremely critical and is achiev ed by interative adjustment.

Selection and Preparation of Specific Tissue Regions For Tem Using Large Epoxy-Embedded Blocks

1973 ◽  
Vol 31 ◽  
pp. 324-325 ◽  
Author(s):  
P. M. Lowrie ◽  
W. S. Tyler
Keyword(s):  
Electron Microscopy ◽  
Anatomical Structures ◽  
Ultrastructural Studies ◽  
Transmission Electron ◽  
Microscopic Evaluation ◽  
Embedded Blocks ◽  
Specific Tissue ◽  
Definition Of ◽  
Areas Of Interest ◽  
Selection Of

The importance of examining stained 1 to 2μ plastic sections by light microscopy has long been recognized, both for increased definition of many histologic features and for selection of specimen samples to be used in ultrastructural studies. Selection of specimens with specific orien ation relative to anatomical structures becomes of critical importance in ultrastructural investigations of organs such as the lung. The uantity of blocks necessary to locate special areas of interest by random sampling is large, however, and the method is lacking in precision. Several methods have been described for selection of specific areas for electron microscopy using light microscopic evaluation of paraffin, epoxy-infiltrated, or epoxy-embedded large blocks from which thick sections were cut. Selected areas from these thick sections were subsequently removed and re-embedded or attached to blank precasted blocks and resectioned for transmission electron microscopy (TEM).

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