Showing papers by "Westinghouse Electric published in 2001"

Predictive maintenance display system

Abstract: A display system in which subsequent failures of plant equipment and plant systems are predicted to occur and in which the probability of failure before a specified date and the probability of failure after a specified date is determined and displayed and in which the calendar date is determined and displayed when the desired probability that the equipment not fail prior to the calendar date is specified The system includes an Equipment Failure And Degradation Module that determines the remaining equipment/system life; a Probability-of-Failure Predictor Module that determines the probability of the equipment/system failing prior to a specified date and the probability of the equipment/system failing after a specified date; and a Date-of-Failure Predictor Module that determines the calendar date that corresponds to a specified probability that equipment not fail prior to the date

Method and apparatus for cooling high temperature components in a gas turbine

Abstract: A combustion turbine having a compressed air cooling circuit that is connected to a nitrogen source. Compressed air is provided to the cooling circuit upon start-up and gradually switched to nitrogen cooling, as the nitrogen becomes available. Transition from compressed air to nitrogen cooling is supplied to the hottest components first in accordance with a pre-selected control scheme. Upon shutdown of the plant, the process is reversed.

Method and apparatus for automatic tissue staining

Abstract: A method and apparatus for specimen slide (710) preparation is disclosed. The method and apparatus of the present invention uses slide trays (700) that have receptacles for at least one specimen slide (710) and an associated reagent park (720). The specimen slide (710) and/or reagent pack (720) includes an identifier (420) that specifies a particular slide preparation protocol that should be followed. The method and apparatus reads the identifier (420) to determine the particular slide preparation protocol and then prepares the specimen slide according to the particular slide preparation protocol. The apparatus may obtain some or all of the reagents needed for the particular slide preparation protocol from the reagent pack (400).

Thermal barrier coating applied with cold spray technique

Abstract: A process (20) for applying a thermal barrier coating (51) to a turbine component (50) including the step (34) of depsoiting a bond coating layer (56) by a cold spray process. The layer of bond coating material may have different depths (80, 82) in different areas of the component (50), and it may have different compositions (60, 62) across its depth. The precise control afforded by the cold spray material deposition step allows the surface of the bond coating material layer to be formed with a predetermined surface roughness or with a plurality of micro-ridges (86) in order to optimize its bond to the ovelying ceramic insulating layer (52).

Thermal barrier coating having high phase stability

Abstract: A device (10) comprising a substrate (22) having a deposited ceramic thermal barrier coating layer (20) characterized by a microstructure having gaps (28) where the thermal barrier coating (20) consists essentially of a pyrochlore crystal structure having a chemical formula consisting essentially of An+2-xBm+2+xO7-y, where A is selected from the group of elements selected from La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and mixtures thereof; where B is selected from the group of elements selected from Zr, Hf, Ti and mixtures thereof; n and m are the valence of A and B respectively, and for -0.5 ≤ x ≤ 0.5, y = formula (I), and excluding the following combinations for x = 0, y = 0: A = La and B = Zr; A = La and B = Hf; A = Gd and B = Hf; and A = Yb and B = Ti. The preferred pyrochlore crystal structure is Sm2Zr2O7, which is stable over the range of operating temperatures of the device (10) up to at least above 1400 °C, and where the thermal barrier coating (30) can be deposited over a separate bottom fluorite thermal barrier coating.

Segmented thermal barrier coating and method of manufacturing the same

Abstract: A thermal barrier coating ( 18 ) having a less dense bottom layer ( 20 ) and a more dense top layer ( 22 ) with a plurality of segmentation gaps ( 28 ) formed in the top layer to provide thermal strain relief. The top layer may be at least 95% of the theoretical density in order to minimize the densification effect during long term operation, and the bottom layer may be no more than 95% of the theoretical density in order to optimize the thermal insulation and strain tolerance properties of the coating. The gaps are formed by a laser engraving process controlled to limit the size of the surface opening to no more than 50 microns in order to limit the aerodynamic impact of the gaps for combustion turbine applications. The laser engraving process is also controlled to form a generally U-shaped bottom geometry ( 54 ) in the gaps in order to minimize the stress concentration effect.

Apparatus and method for combusting low quality fuel

Abstract: A gas turbine (12) capable of combusting a low quality gaseous fuel having a ratio of flammability limits less than 2, or a heat value below 100 BTU/SCF. A high quality fuel is burned simultaneously with the low quality fuel to eliminate instability in the combustion flame. A sensor (46) is used to monitor at least one parameter of the flame indicative of instability. A controller (50) having the sensor signal (48) as input is programmed to control the relative flow rates of the low quality and high quality fuels. When instability is detected, the flow rate of high quality fuel is automatically increased in relation to the flow rate of low quality fuel to restore stability.

Modular resonators for suppressing combustion instabilities in gas turbine power plants

Abstract: A resonator module for a combustion turbine power plant, where the combustion turbine power plant defines a flow path. The resonator module includes a first member, an a second member. The first member has a size substantially smaller than the diameter of said flow path and a plurality of openings therethrough. The openings are in fluid communication with the flow path. The second member has a size generally equal to said first member. The second member is in a generally spaced relation to the first member and encloses a volume of gas between the first and second members.

Cooling structure and method of manufacturing the same

Abstract: A method of forming a cooling feature (28) on a surface (14) of a substrate (12) to protect the substrate from a high temperature environment The cooling feature is formed by first depositing a layer of a masking material (16) such as epoxy resin on the surface of the substrate A pattern of voids (18) is then cut into the masking material by a laser engraving process which exposes portions of the substrate surface A plurality of supports (20) are then formed by electroplating a support material onto the exposed portions of the substrate surface A layer of material is then electroplated onto the supports and over the masking material to form a skin that interconnects the supports Finally, the remaining portions of the masking material are removed to form a plurality of cooling channels (26) defined by the supports, skin and substrate surface An additional layer of material (42) may be deposited onto a top surface (50) of the cooling feature to provide additional thermal and/or mechanical protection

Physical and chemical determinants of colloid transport and deposition in water-unsaturated sand and Yucca Mountain tuff material.

Abstract: Colloid mobility was determined in a system consisting of quartz sand or crushed Yucca Mountain tuff, simulated groundwater (J-13), and hydrophilic latex particles. Water content (theta) and ionic strength (I; DI water, 0.1x, 1x, 10x groundwater dilution) were manipulated to define limiting conditions for colloid transport atthe Yucca Mountain site. Colloid transport, measured with a centrifuge method at relatively high theta (saturation >36% for sand, >62% for crushed tuff) in DI water, was equivalent to transport at 100% saturation measured with conventional columns. When variables were isolated, increasing I and decreasing theta resulted in a greater extent of colloid deposition; I was more important at higher theta; physical properties were more important at lower theta. I and theta had an interactive effect on colloid deposition whereby synergism was generally observed, especially for simulated groundwater (1x); antagonism was observed at 10x groundwater dilution. At 19% moisture saturation on the crushed tuff, a decreasing rate of colloid deposition was observed. This corresponded to a hydrodynamic condition of 79% immobile water where solute tracers were excluded from a fraction of the pore volume. This suggests that a portion of the favorable sites for deposition were associated with the excluded or immobile water domain and were not accessible to colloids.

Experimental study of crack growth in thin sheet 2024-T3 aluminum under tension-torsion loading

Abstract: To assess the viability of using a critical COD criterion for flaws in 2024-T3 aluminum experiencing tension stresses (SP) and torsion stresses (ST), the enclosed work presents (a) a complete set of measurements for critical COD during crack growth under nominal tension-torsion loading, (b) the evolution of crack path with crack growth and (c) crack surface shape as a function of loading. Data from this work will provide an important experimental database for use in assessing the predictive capability of advanced, three-dimensional, crack growth simulation tools. Results for COD during crack growth under tension-torsion loading indicates that the measured critical COD for tension-torsion loading is constant during crack growth. In addition, the value of COD measured using image correlation methods is approximately 8% larger than observed for in-plane tension-shear, with much of the increase apparently due to specimen deformations in the crack tip vicinity. In addition, crack path evolution data for the range of ST/SP considered in this work show that the crack experiences both tunneling and slant fracture during loading, with tunneling rapidly decreasing (a) as crack growth progresses for all ST/SP values or (b) as ST/SP increases. Furthermore, results indicate that tearing during tension-torsion loading always occurs in a manner so that the crack surfaces tend to interfere during growth. Finally, crack surface shape data indicates that, with the exception of a small secondary transition, the direction of crack growth remains stable along a straight line oriented along the initial fatigue crack direction for the range of ST/SP being considered.

Convergent and divergent points in catabolic pathways involved in utilization of fluoranthene, naphthalene, anthracene, and phenanthrene by Sphingomonas paucimobilis var. EPA505.

Abstract: Catabolic pathways for utilization of naphthalene (NAP), anthracene (ANT), phenanthrene (PHE), and fluoranthene (FLA) by Sphingomonas paucimobilis EPA505 were identified. Accumulation of catabolic intermediates was investigated with three classes of Tn5 mutants with the following polycyclic aromatic hydrocarbon (PAH)-negative phenotypes; (class I NAP(-) PHE(-) FLA(-), class II NAP(-) PHE(-), and class III FLA(-)). Class I mutant 200pbhA had a Tn5 insertion within a meta ring fission dioxygenase (pbhA), and a ferredoxin subunit gene (pbhB) resided directly downstream. Mutant 200pbhA and other class I mutants lost the ability to catalyze the initial dihydroxylation step and did not transform NAP, ANT, PHE, or FLA. Class I mutant 401 accumulated salicylic acid, 2-hydroxy-3-naphthoic acid, 1-hydroxy-2-naphthoic acid, and hydroxyacenaphthoic acid during incubation with NAP, ANT, PHE, or FLA, respectively. Class II mutant 132pbhC contained the Tn5 insertion in an aldolase hydratase (pbhC) and accumulated what appeared to be meta ring fission products: trans-o-hydroxybenzylidene pyruvate, trans-o-hydroxynaphylidene pyruvate, and trans-o-hydroxynaphthyl-oxobutenoic acid when incubated with NAP, ANT, and PHE, respectively. When mutant 132pbhC was incubated with 1-hydroxy-2-naphthoic acid, it accumulated trans-o-hydroxybenzylidene pyruvate. Class III mutant 104ppdk had a Tn5 insertion in a pyruvate phosphate dikinase gene that affected expression of a FLA-specific gene and accumulated a proposed meta ring fission product; trans-o-hydroxyacenaphyl-oxobutenoic acid during incubation with FLA. Trans-o-hydroxyacenaphyl-oxobutenoic acid was degraded to acenaphthenone that accumulated with class III mutant 611. Acenaphthenone was oxidized via incorporation of one molecule of dioxygen by another oxygenase. 2,3-Dihydroxybenzoic acid was the final FLA-derived catabolic intermediate detected. Analysis of PAH utilization mutants revealed that there are convergent and divergent points involved in NAP, ANT, PHE, and FLA utilization by S. paucimobilis EPA505.

Thermal barrier coating system for turbine components

Abstract: A composite thermal barrier coating system includes a first composite thermal barrier coating over a portion of a substrate, and a second deposited thermal barrier coating over edge portions of the substrate. The first composite coating is relatively thick and preferably includes friable graded insulation comprising an abradable honeycomb metallic structure filled with high thermal expansion ceramic hollow spheres in a phosphate bonded matrix. The second deposited edge coating is relatively thin and preferably comprises an electron beam physical vapor deposited thermal barrier coating comprising ZrO2 and Y2O3. The friable graded insulation may be manufactured to thicknesses in excess of current thermal barrier coating systems, thereby imparting greater thermal protection. Superior erosion resistance and abrasion properties are also achieved. The composite thermal barrier coating system is useful on combustion turbine components such as ring seal segments, vane segment shrouds, transitions and combustors.

Transient liquid phase bonding repair for advanced turbine blades and vanes

Abstract: A method of repairing gas turbine engine components is provided. The method includes removing the damaged portion and fabricating an insert to match the removed portion. The insert is precision machined and crystallographically matched to the original component, and then bonded to this component using transient liquid phase bonding techniques and suitable heat treatment.

Enhanced dielectric strength mica tapes

Abstract: A flexible insulating tape (16) contains a flexible backing (18) and a mica or mica-like silicate matrix (20) with insulating resin (17) and intercalated metal ions (12) between the matrix (2) where the resin (17) and the ions (12) are intimately disposed next to the mica (20).

Considerations for the weldability of types 304L and 316L stainless steel

Abstract: The susceptibility of austenitic stainless steels to the formation of two distinct weld defects, solidification cracking and lack of penetration, is related to the chemical composition of the base and filler material. The propensity for cracking is determined primarily by the solidification mode and the amount of residual tramp elements such as phosphorous and sulfur. High sulfur levels can lead to weld centerline cracking and heat affected zone (HAZ) cracking while very low sulfur levels (less than ∼50 ppm) in types 304L and 316L are associated with lack of penetration weld defects and a distinct loss in puddle control during fusion welding. A calculated Creq to Nieq ratio of 1.52 to 1.9 is recommended to control the primary mode of solidification and prevent solidification cracks in type 304L while the Creq/Nieq ratio of 1.42 to 1.9 is recommended for type 316L stainless steel. A lower limit of 50 ppm sulfur is recommended to avoid possible lack of penetration. These ranges should be validated by welding trials for specific weld processes and applications.

Dead reckoning pedometer

Abstract: A system to determine the location of a person within a structure utilizes a magnetometer, magnets, pressure sensors and a CPU to calculate the length and direction of each step. The data may be displayed to the wearer, preferably on a map or floorplan and may be broadcast to persons outside the structure.

Screening of algal strains for metal removal capabilities

Abstract: Eight algal species were tested for their ability to remove five toxic metalsduring 30-min exposures to single-metal (1 mg L-1) solutions at pH7. Efficacy of metal bioremoval varied according to algal species and metal. Al+3 was best removed by the thermophilic blue-green alga(cyanobacterium) Mastigocladus laminosus, Hg+2 and Zn+2 by the thermophilic and acidophilic red alga Cyanidiumcaldarium, and Cd+2 by C. caldarium and the green alga Scenedesmus quadricauda. All of these alga/metal combinations resultedin >90% metal removal. However, none of the eight algal speciesremoved more than 10% of Cr+6. Results indicate that some toxicmetals are more readily removed than others are by algae and that selectionof appropriate strains could potentially enhance bioremoval of specificmetals from wastewater at neutral pH.

Remote controlled inspection vehicle utilizing magnetic adhesion to traverse nonhorizontal, nonflat, ferromagnetic surfaces

Abstract: A remote controlled inspection vehicle provides interchangeable modules, permitting the vehicle to be easily configured to perform a wide variety of tasks. The vehicle includes at least one frame module having a pair of drive modules on either side. Each drive module includes a continuous track surrounding a permanent magnet, and is dimensioned and configured to pivot around its longitudinal axis. The frame modules are dimensioned and configured to be hingedly secured to other frame modules, end effectors including various sensors for performing inspections, and tail units to assist in placing the vehicle in the desired environment.

Method of manufacturing small profile medical devices

Abstract: A method of manufacturing medical devices of a size sufficiently small to be passed through the vasculature of the body, and more particularly through the small vessels of the brain. The method includes the steps of laser cutting a pattern of apertures in the surface of a tubular workpiece, radially compressing the tubular workpiece to reduce the outer dimensions of the workpiece and heat setting the reduced diameter workpiece to form the very small medical device.

Self-repairing metal oxides

Abstract: The oxidation of Cu, Zr, and alloys forming chromia, alumina, and zirconia was studied in a closed reaction chamber in O2 gas near 20 mbar. Information on the position of oxide growth has been gained from the 18O/SIMS technique. Rates of O2 dissociation on metal oxides, Au, and Pt have been evaluated from measurements in labeled O2. The experimental results indicate that hydrogen in the metal substrates induces increased metal-ion transport in internal oxide surfaces during oxidation, which leads to increased oxide growth at the oxide–gas interface. Experiments also show that oxides of rare-earth metals (REM) and Pt catalyze the dissociation of O2. An increased rate of O2 dissociation can lead to increased transport of oxygen ions in the oxides and increased oxide growth at the substrate–oxide interface. A balanced transport of metal and oxygen ions in metal oxides that leads to oxide growth at both the metal–oxide and at the oxide–gas interface is found to be favorable for the formation of protective oxides with good adherence to the metal substrate. Depending on the original proporation of metal–to–oxygen ion transport in the oxide, an addition of hydrogen will increase or decrease the oxidation kinetics. In analogy, an addition of REM will increase or decrease the oxidation kinetics, depending on the original proportion of metal-to-oxygen ion transport.

Ceramic matrix composite having improved interlaminar strength

Abstract: A ceramic matrix composite material (10) having a plurality of interlaminar stitches (16) as shown in figure. The stitches are formed by directing laser energy into the material to melt and recast zones of the material in a direction transverse to the layers of reinforcing fibers (12). The stitches not only improve the interlaminar strength of the material, but they also increase the through-thickness thermal conductivity of the material, thereby reducing thermal-induced stresses. The zones of recast material (18) may define holes (20) extending at least partially through the thickness of the material. The holes may be filled with a filler material (24), thereby mitigating any adverse loss-of-area effect created by the holes.

Railway locomotive brake controller

Abstract: An integrated locomotive braking and ECP braking control on a lead locomotive for implementing braking effort on all locomotives in a manner relative to braking effort applied on ECP freight cars. On the lead locomotive, a data interface can be established between an head-end-unit and a brake controller. The head-end-unit can electrically signal each ECP freight car to carry out braking commands. The integrated brake control can include a CPU, as part of either the brake controller or the head-end-unit, which can be programmed to provide braking effort on the lead locomotive relative to the braking effort applied on the ECP freight cars. The braking on the lead locomotive is implemented by the brake controller by controlling the independent brake relative to the braking effort commanded on the ECP freight cars. The independent brake on non-ECP trailing locomotives is connected to the lead locomotive independent brake via a standard independent brake pneumatic connection. As a result, the same braking effort applied on the lead locomotive via the independent brake is automatically implemented on the non-ECP trailing locomotives via the independent brake pneumatic connection such that all locomotives are braked relative to braking on the ECP freight cars.

Remote spray coating of nuclear cross-under piping

Abstract: A machine (10) that can clean and spray coat the inside of a hollow pipe (14) can contain a support bar (16) and associated motors (6 and 8) with a moveable carriage (12) which mounts a thermal spray coating device (28) and/or an abrasion cleaning/profiling head (30) where a programmable controller external to the pipe is capable of controlling the motors (6 and 8).

Studies on the surface chemistry of oxide films formed on IN-738LC superalloy at elevated temperatures in dry air

Abstract: The oxidation behavior of IN-738LC was studied to develop high-temperature materials for low cost and highly efficient turbine systems The present study was undertaken to investigate the kinetics and the surface chemistry of the oxide films formed during isothermal oxidation of IN-738LC superalloy in the temperature range 1123–1223 K in dry air The oxidation kinetics followed the parabolic law The activation energy of oxidation was 264 kJ mol−1 The scaling process is controlled mainly by the diffusion of chromium ions through the intermediate chromia layer in the scale The surface morphology and the oxide phases of the scale were characterized by SEM, XRD, and EDS studies XRD analysis revealed the presence of NiO, NiAl2O4, NiCr2O4 spinel, Al2O3, and Cr2O3 on the top-scale surface The scale surface and cross section were further characterized using X-ray photoelectron spectroscopy (XPS), which revealed the presence of NiO, Ni2O3, NiAl2O4, Al2O3, and TiO2 on the top-oxide surface The chromia layer was found to be underneath the top scale The chromia layer also contains NiCr2O4 and NiAl2O4 spinels along with Al2O3 Application of XPS was found to be successful to understand the oxide-scale chemistry in terms of the oxide-growth mechanism of IN-738LC at elevated temperatures

Pre-segmented squealer tip for turbine blades

Abstract: A turbine blade having a pre-segmented squealer tip is provided. The segment or slots in the squealer tip are located in regions of maximum stress, and reduce cracking of the squealer tip and propagation of cracks into the airfoil. The slots are preferably filled with a corrosion resistant material which is more ductile than the base alloy.

Demonstration of Active Control of Combustion Instabilities on a Full-Scale Gas Turbine Combustor

Abstract: This paper presents the results of an investigation of active control of combustion instabilities in a natural gas, high-pressure, full-scale gas turbine combustor that was retrofitted with an Active Control System (ACS). The combustor test rig simulates the geometry, inlet airflow distribution, and pressurization of a can-type combustor that exhibits dynamic flame instabilities at some off-design operating conditions. Two essential features of the investigated ACS are 1) a real-time mode observer that identified the frequencies, amplitudes and phases of the dominant modes in the pressure signal and 2) a fast response servo valve that can modulate a large portion of the gaseous fuel. Two active control configurations were studied. In the first configuration, the actuator was mounted on one of two premixed fuel stages, and in the second configuration it was mounted on the inlet to the stabilizing diffusion stage. In both configurations, the ACS damped combustion instabilities, attenuating the dominant mode by up to 15dB and reducing the overall broadband noise by 30-40%. NOx emissions were also reduced by approximately 10% when control was applied. Finally, this study demonstrated the importance of having a fast multiple-mode observer when dealing with complex combustion processes with inherently large time delays.Copyright © 2001 by ASME

Spring applied parking brake assembly having a manual quick release feature

Abstract: A spring applied parking brake assembly for a railroad vehicle braking system is provided for an automatic application of the parking brake in the absence of an air source. The spring applied parking brake assembly comprises a cylindrical casing containing a piston assembly. The piston assembly is mounted for longitudinal movement within the casing upon the application and/or removal of pneumatic pressure to the piston assembly. The piston assembly is associated with a force transfer lever of the braking system so as to apply a force to this force transfer lever upon longitudinal movement of the piston assembly. At least one spring member is provided within the cylindrical casing. This spring member applies a constant force to the piston assembly such that longitudinal movement of the piston assembly automatically occurs upon removal of pneumatic pressure to the braking system, causing the piston assembly to retract within the casing and the force transfer lever to rotate in a direction to initiate a brake application. Thus, once the train is removed from the train consist and the air supply for the pneumatic braking system has been disconnected, the brakes of the train are automatically applied. A manual quick release system is also provided which allows the parking brake to be released during shunting operations or anytime that it is desirable to move the vehicle in the absence of air.