Plant components

AEBIL A New Acoustic Emission System for On-line Structural Integrety Monitoring of Critical Plant Components. 

Thermal power plant components operated at high temperatures (>500°C) and pressures, such as superheater headers, steamline sections and Y-junctions, deserve great attention for both operation safety and plant availability concerns. In particular, during plant operation transients -startups, shutdowns or load transients - the above components may undergo high rates of temperature / pressure variations and, consequently, non-negligible time-dependent stresses which, in turn, may locally destabilize existing cracks and cause the release of acoustic emission. 

After preliminary shop tests on different mockups (e.g. superheater and reheater headers and steamline pipe sections), since 1996 AEBIL systems have been installed and are at work on several power plant components. In particular, three different components have been monitored throughout 1997 (monitoring still under way at the time being) ... 

The "SIMON" Project ("On-line acoustic monitoring of structural integrity of critical power plant components operating at high temperatures") had a duration of 4 years (1.10.1993 -30.09.1997) the Project Consortium included CISE (Project Coordinator, I), MITSUI BABCOCK ENERGY (UK), HERIOT-WATT UNIVERSITY (IK), PROET / EDP (P) and ENEL (I). 

Assessing the effectiveness and reliability of Acoustic Emission (AE) in continuous, on-line monitoring of the structural integrity of critical thermal power plant components, such as steam headers and steamline sections, is the main objective of the work reported in this paper. This is part of the work carried within the BRITE - EURAM 6056 "SIMON" Project from 10.1993 to 9.1997 with the support of the EU Commission. The "SIMON" Project Consortium included CISE [I, coordinator], MITSUI BABCOCK ENERGY [UK] HERIOT WATT University [UK], PROET / EDP[P]andENEL[I],... 

F. Cattaneo, C. De Michelis, S. Ghia, G.M.Piana "AEBIL a new acoustic emission system for on-line structural integrity monitoring of critical power plant components" to be presented at the 7th European Conference on Non-Destructive Testing, Copenhagen, 26-29 May 1998. 

M. MAYOS, A. SCHUMM, C. SOORS, O. VAILHEN, E. FLEUET Application of the PACE system to the analysis of multitechnique NDT data on a power plant component -Review of Progress in QNDE, vol. 16B, eds. D. Thompson and D.E. Chimenti, Plenum, 1997, pp. 2175-2182. 

BE-5935 Inspection and maintenance of power plant components Mr. K. Lieven MrTGmbH... 

SP<249 Implementation of power plant component life assessment Dr. A. Jovanovic MPA Stuttgail... 

Due to the many problems concerning steam generators of nuclear power plants over the last decades, we developed our own inspection equipment and services. Next to this main activity, we provide inspections for nuclear power plants components such as thimbles, guide carts and baffle bolts. 

Produced from a.tura.1 Ga.s, Cost assessments of methanol produced from natural gas have been performed (13—18). Projections depend on such factors as the estimated costs of the methanol production faciUty, the value of the feedstock, and operating, maintenance, and shipping costs. Estimates vary for each of these factors. Costs also depend on the value of oil. Oil price not only affects the value of natural gas, it also affects the costs of plant components, labor, and shipping. 

The American Society of Mechanical Engineers (ASME) United Engineering Center 345 East 47th Street New York, NY 10017 The ASME Boiler and Pressure Vessel Code, under the cognisance of the ASME PoHcy Board, Codes, and Standards, considers the interdependence of design procedures, material selection, fabrication procedures, inspection, and test methods that affect the safety of boilers, pressure vessels, and nuclear-plant components, whose failures could endanger the operators or the pubHc (see Nuclearreactors). It does not cover other aspects of these topics that affect operation, maintenance, or nonha2ardous deterioration. 

In the simplest terms, a fault-tree for risk analysis requires the following information probabiUty of detection of a particular anomaly for an NDE system, repair or replacement decision for an item judged defective, probabiUty of failure of the anomaly, cost of failure, cost of inspection, and cost of repair. Implementation of a risk-based inspection system should lead to an overall improvement in the inspection costs as well as in the safety in operation for a plant, component, or a system. Unless the database is well estabUshed, however, costs may fluctuate considerably. 

Glass Plants Components Process Pipe Fitting HardirarefJoining and Adaption, Coming QVE Pipe, QVE Coming, New York, 1989 to 1992. 

III. Rules for Construc tion of Nuclear Power Plant Components IV Heating Boilers V Nondestructive Examination T. Rules for Care and Operation of Heating Boilers TI. Guidelines for the Care of Power Boilers... 

XI. Rules for Inservice Inspection of Nuclear Power Plant Components... 

ASME Code Sec. Ill Nuclear Power Plant Components This section of the code includes vessels, storage tanks, and concrete containment vessels as well as other nonvesseJ items. 

The use of electrochemical protection in the chemical industry started about 20 years ago, which is somewhat recent, compared with its use for buried pipelines 40 years ago. Adoption was slow because the internal protection has to be tailored to the individual plant, which is not the case with the external protection of buried objects. Interest in internal protection came from the increasing need for greater safety for operating plants, increased demands for corrosion resistance, and larger plant components. While questions of its economy cannot generally be answered (see Section 22.6), the costs of electrochemical protection are generally less than the cost of equivalent and reliable coatings or corrosion-resistant materials. 

WASH-1400 did not analyze seismic events, but if they had, the risk they assessed would have been larger. Earthquake analysis was part of the FSAR for licensing a plant and had been practiced for some time before the RSS. This analysis included earthquake frequencies from historical records, ground-coupling models to estimate the intensity and frequency spectrum of the acceleration, and spring-mass models to estimate the forces on plant components under the... 

Failure frequencies of structures, equipment, and piping are related to their acceleration which is related to the ground-motion of the plant s foundation (e.g., the peak ground acceleration). For PSA, it is useful to present the seismic hazard at the site as a family of hazard curves with different nonexceedence-probability levels (Figure 5.1-3). By selecting various values of the peak ground acceleration, the acceleration and forces on the plant components may be obtained as described in the following. 

The fragility analysis evaluates the conditional fraction of failure of plant structures and equipment as a function of ground motion. The seismically initiated failure of plant components is expressed in terms spectral acceleration at 5.0 Hz which is between the fundamental frequency of the... 

Typical events that are considered are fire, explosion, ship collision, and the failure of pressurized storage vessels for which historical data established the failure frequencies. Assessment of consequences was based partly on conservative treatment of past experience. For example ilic assessment of the number of casualties from the release of a toxic material was based on past histoiy conditioned by knowledge of the toxicology and the prevailing weather conditions. An altemati. e used fault trees to estimate probabilities and identify the consequences. Credit is taken in this process for preventative measures in design, operation, and maintenance procedures. Historical data provide reliability expected from plant components and humans. 

Drago, J. P. et al., In-Plant Reliability Database for Nuclear Plant Components Interim Data Report, The Pump Component, ORNL, December 1972. 

Borkowski, R, J. et al, The In-Plant Reliability Databa.se for Nuclear Plant Components Interim Report - The Valve Component. ... 

Drago, J. P., Borkowski, R. J., Pike, D. H., and Goldberg F. F. The In-Plant Reliability Data Base for Nuclear Power Plant Components Data Collection and Methodology Report. NUREG/ CR-2641, ORNL/TM-9216, January 1985. 

Tils In-Plant Reliability Data Base lor Nudear Plant Components... 

Fienemann, M. and C. Mason. Nuclear Plant Component Nomenclature Hierarchy for Failure and Repair Reporting. SAI/NY-R-81-4, 1981. 

The plant components selected should be of proven design supported by strong reference installations. Modem trends are moving towards reduction in manning levels, and the use of central computer control and supervisory systems also ensures maximum efficiency of plant operation. 

Griskin et reported that there is no apparent effect of steam pressure on the rate of oxidation of Cr-Ni steels at temperatures between 600°C and 650°C at 10.1-20.2 MPa. Similar observations for Cr-Mo and Cr-Mo-V steels between 500°C and 600°C have been made by Wiles" . She compared low-alloy steel samples exposed to 101 kPa steam with power plant components that had operated for up to 150000b in steam at 17.25 MPa and found no significant difference in the oxidation rates (Fig. 7.11). 

Corrosion of condensate lines is a serious problem. It is compounded where both oxygen and carbon dioxide are present because it causes considerable quantities of hematite (Fe203) to develop. Corrosion of other boiler plant components, such as FW heaters, adds more metals to the mix, and corrosion debris typically includes iron, copper, nickel, zinc, and chromium oxides. 

Some herbs are standardized for several active constituents, while others are standardized to a single active ingredient. St. John s wort is standardized to contain 0.3% hypericin, whereas ginkgo is standardized to contain 24% flavone glycosides and 6% ter-pene lactones. However, standardizing an herb product to one or more plant component(s) that are identifiable by assay may be incorrect. Many herbalists believe that the whole plant contributes to the efficacy and that there are many unknown active compounds in each plant [6]. 

TES-based systems are usually economically justifiable when the annualized capital and operating costs are less than those for primary generating equipment supplying the same service loads and periods. TES is often installed to reduce initial costs of other plant components and operating costs. Lower initial equipment costs are usually obtained when large durations occur between periods of energy demand. Secondary capital costs may also be lower for TES-based systems. For example, the electrical service equipment size can sometimes be reduced when energy demand is lowered. 

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