Degradation Evaluation of the Gas Turbine Hot-Gas-Path Component

2005 ◽  
Vol 297-300 ◽  
pp. 2266-2271
Author(s):  
Jine Sung Jung ◽  
S.Y. Chang ◽  
Keun Bong Yoo ◽  
Gee Wook Song ◽  
Min Sung Kang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Gas Turbine ◽  
Coating Layer ◽  
Interdiffusion Zone ◽  
Hot Gas ◽  
Impact Tests ◽  
Path Component ◽  
Coating Layers ◽  
Degradation Evaluation

Degradation of the gas turbine hot-gas-path components, the 1st stage blades and vanes, serviced for a period was evaluated by measuring the mechanical properties. For this, tensile and impact tests on these gas turbine parts were performed. Microstructure of the substrate and coating layers were also observed. The mechanical properties of the serviced blades were degraded by about 30% comparing with those of unused ones. In terms of the microstructure, the dissolution of the secondary g’ phase and subsequent coarsening of precipitates were observed in the substrate. And the interdiffusion zone near the coating layer was disappeared.

Degradation Evaluation of the Gas Turbine Hot-Gas-Path Component

2005 ◽  
pp. 2266-2271
Author(s):  
Jine Sung Jung ◽  
S.Y. Chang ◽  
Keun Bong Yoo ◽  
Gee Wook Song ◽  
Min Sung Kang ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Hot Gas ◽  
Path Component ◽  
Degradation Evaluation

scholarly journals Microstructure of Joint between Stranded Wire and Substrate Welded by Ultrasonic Welding

2019 ◽  
Vol 9 (3) ◽  
pp. 534 ◽  
Author(s):  
Chihiro Iwamoto ◽  
Keisuke Yamauchi ◽  
Kazuki Motomura ◽  
Yoichi Hashimoto ◽  
Kensuke Hamada
Keyword(s):  
Mechanical Properties ◽  
Cross Sections ◽  
Coating Layer ◽  
Ultrasonic Welding ◽  
Efficient Technique ◽  
High Quality ◽  
Cu Substrate ◽  
Coating Layers ◽  
Microscopy Techniques

In order to improvement electronic and mechanical properties, welding between stranded wires and terminals is important. However, welding methods to obtain high-quality joints using stranded wires are still limited. In this report, we applied ultrasonic welding to join a Cu stranded wire to a Cu substrate. Cross-sections of the weldments were taken and observed by several microscopy techniques to elucidate the weldability and soundness of the joints. After ultrasonic welding, each wire in the stranded wire was joined together at the region where the stranded wire was joined to the substrate without any defect. Each wire was welded through the Ag coating layer, and the stranded wire and the substrate was also welded through the outermost coating layers. It was found that ultrasonic welding is an efficient technique for producing high quality joints without any defect at the interface.

Degradation Assessment of Gas Turbine Hot Gas Path Components

2016 ◽  
Vol 1133 ◽  
pp. 376-380
Author(s):  
Ahmad Afiq Pauzi
Keyword(s):  
Gas Turbine ◽  
Fuel Mixture ◽  
Operating Conditions ◽  
Research Project ◽  
Damage Mechanisms ◽  
Damage And Failure ◽  
Hot Gas ◽  
Failure Risk ◽  
Path Component ◽  
Damage Processes

Hot gas path component consists of components designed to burn air-fuel mixture in combustion section and provide hot gasses to the turbine section where mechanical power is produced. The aim of this research project is expected to improve the current practices of managing degradation of hot gas path components. Understanding the damage mechanisms is of great interest in reducing the damage and failure risk. In this research, a study was conducted on F-Class type gas turbine hot gas path components assembly. It involved extensive examination and testing of the components which had been in operations for 24,000 hours since the last shutdown. Various factors such as installation, operating conditions, hardness and material of constructions were also investigated. This paper reports the initial findings of the study of hot gas path components degradation. It describes the damage observed on the affected areas of the components and proposes the factors that contribute to the damage processes. Potential solutions for mitigating the damages are also discussed.

Development of Risk-Based Maintenance Software for Gas Turbines

2007 ◽  
Author(s):  
Tomoharu Fujii ◽  
Terutaka Fujioka ◽  
Chris Ablitt ◽  
Julian Speck ◽  
Brian Cane
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Damage Mechanism ◽  
Risk Assessments ◽  
Inspection Planning ◽  
Risk Matrix ◽  
Hot Gas ◽  
Path Component ◽  
Software Risk ◽  
Maintenance And Inspection

Risk-based maintenance software has been developed to perform risk-based maintenance and inspection planning on gas turbine hot gas path components. The software allows the user to easily prepare a risk matrix, plotting every active damage mechanism for each hot gas path component. Based on the result of the risk assessments the components can be ranked, allowing inspection plans to be focused and prioritized and aiding the user to identify the most appropriate and effective risk mitigating activity within the software. Risk assessments are performed on a component-by-component basis, with the software’s scope including all combustor and turbine hot gas path components. The software also contains comprehensive help documents to aid the user in identifying and assessing peculiar damage mechanisms and prescribing the most effective inspection methods for gas turbines.

Hot-Gas-Path Life Extension Options for the V94.2 Gas Turbine

2000 ◽  
Author(s):  
Gerhard Bohrenkämper ◽  
Herbert Bals ◽  
Ursel Wrede ◽  
René Umlauft
Keyword(s):  
Power Plant ◽  
Service Life ◽  
Gas Turbine ◽  
Power Plants ◽  
Combined Cycle ◽  
Life Extension ◽  
Hot Gas ◽  
Maintenance Program ◽  
Path Component ◽  
Strategic Options

Gas turbine and combined cycle power plants are typically designed for a service life of over 30 years. If operated at base load in continuous duty, the gas turbine hot-gas-path components for example in a combined-cycle power plant need repair and replacement according to the maintenance program several times during plant life. Most of the hot components would reach the end of their service life, e.g. 100,000 equivalent operating hours (EOH), after 10 to 12 years. As this is well before the end of the overall plant service life defined in the power plant concept, such plant applications therefore necessitate life extension measures enabling to continuing operation beyond 100,000 EOH. This paper presents strategic options for hot-gas-path component life entension.

Measurement of mechanical properties of multilayer waterborne coatings on wood by nanoindentation

Holzforschung ◽  
2019 ◽  
Vol 73 (9) ◽  
pp. 871-877 ◽  
Author(s):  
Yan Wu ◽  
Jiamin Wu ◽  
Siqun Wang ◽  
Xinhao Feng ◽  
Hong Chen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cell Walls ◽  
Coating Layer ◽  
Intact Cell ◽  
Bonding Mechanism ◽  
Thickness Direction ◽  
Waterborne Coatings ◽  
Coating Layers ◽  
Wood Surfaces ◽  
Coating Layer Thickness

AbstractWaterborne coatings are widely used for environmental protection. However, they lead to many defects and lower the mechanical properties when applied to wood surfaces. To address this challenge, the effects of multilayer waterborne polycrylic coatings on the mechanical properties of southern pine cell walls were investigated by nanoindentation. The experimental results indicated that the coating layers significantly reduced the elastic modulus (Er) and hardness (H) values than the wood cell walls. TheErandHvalues measured along the coating layer thickness direction increased significantly as the distance of the indents to the wood surface decreased. Intact cell walls adjacent to or away from the coating layers had higherErandHvalues than partial ones. This study will also be useful in helping to understand the bonding mechanism at the interface between coatings and wood cell walls.

scholarly journals Deformation mechanics of sputtered copper layers during nanoindentation tests

2020 ◽  
Vol 14 (1) ◽  
pp. 6504-6513
Author(s):  
M. A. A. Afripin ◽  
N. A. Fadil ◽  
M. Nasir Tamin
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Constitutive Equation ◽  
Coating Layer ◽  
Peak Load ◽  
Load Level ◽  
Hardening Behavior ◽  
Rate Dependent ◽  
Deformation Mechanics ◽  
Coating Layers

The mechanical properties of the thin sputtered copper layer on the SiO2-coated silicon substrate is needed as part of the requirements in quantifying the reliability of the Through-Silicon Via (TSV) interconnects. In this respect, two different Cu coating layers, each from the different sputtering process, are examined. A series of nanoindentation tests are performed on the Cu coating layer samples with indenter speeds ranging from 80 to 400 nm/s, and the indentation depths of 320 nm. The properties of elastic modulus, hardness and the hardening behavior of the Cu coating layers have been quantified. Results show that the coating with higher contamination of C at 8.41 wt. % displays a significant hardening and a peak load level, as reflected in the measured nanoindentation load-displacement curves. However, insignificant effect of the applied probe displacement speeds up to 400 nm/s on the resulting properties of the coating is registered. The Johnson-Cook constitutive equation adequately describes the strain rate-dependent hardening behavior of the Cu coating layer.

Development of Diagnostic Tools for Real Time Assessment of Gas Turbine Hot Gas Path Component Temperatures: A Preliminary Study

2002 ◽  
Author(s):  
Carlo Carcasci ◽  
Bruno Facchini ◽  
Francesco Grillo ◽  
Erio Benvenuti ◽  
Gianni Mochi
Keyword(s):  
Gas Turbine ◽  
Evaluation System ◽  
Information Needs ◽  
Effective Means ◽  
Operating Conditions ◽  
Design Stage ◽  
Diagnostic Tools ◽  
Hot Gas ◽  
Path Component ◽  
Wide Range

This paper outlines a part of the work under way at GE Oil and Gas – Nuovo Pignone to develop advanced diagnostic tools to evaluate gas turbine hot gas path components life on the basis of actual operating data continuously recorded by remote monitoring systems. The system aims at correlating component metal temperatures and stresses as a function of operating performance data measured through standard machine instrumentation. Monitored data is processed by a new inverse-cycle algorithm to evaluate gas-path temperatures and pressures. The generated gas path information needs then to be correlated to metal temperatures and stresses with precision suitable for input to algorithms evaluating creep, oxidation and hot corrosion damage. Typically, calculations of gas path data to metal temperatures and stresses are performed at the design stage for a limited number of critical operating conditions by using complex and sophisticated CFD and structural/thermal analysis computer codes. For applications to diagnostic, direct use of such tools for any monitored sets of data would be impracticable. On the other hand, they represent the most effective means for assessing hot gas path component temperatures with adequate accuracy, particularly on last generation engines with substantial turbine blade and nozzle cooling. The approach chosen and described herein consists in extensively using high level design tools over a wide range of turbine operating conditions and use the results to produce equations and maps linking field monitored data to component temperatures suitable for easy implementation into a life evaluation system. In the paper major aspects of the above work are reviewed and synthesized, and significant steps in the first application to a turbine first stage cooled blade are illustrated.

Cracking at the fold in double layer coated paper: the influence of latex and starch composition

TAPPI Journal ◽  
2019 ◽  
Vol 18 (2) ◽  
pp. 93-99
Author(s):  
SEYYED MOHAMMAD HASHEMI NAJAFI ◽  
DOUGLAS BOUSFIELD, ◽  
MEHDI TAJVIDI
Keyword(s):  
Mechanical Properties ◽  
Double Layer ◽  
Starch Content ◽  
Single Layer ◽  
Double Layers ◽  
Coated Paper ◽  
Coated Papers ◽  
Coating Layers ◽  
Scanned Images ◽  
Packaging Paper

Cracking at the fold of publication and packaging paper grades is a serious problem that can lead to rejection of product. Recent work has revealed some basic mechanisms and the influence of various parameters on the extent of crack area, but no studies are reported using coating layers with known mechanical properties, especially for double-coated systems. In this study, coating layers with different and known mechanical properties were used to characterize crack formation during folding. The coating formulations were applied on two different basis weight papers, and the coated papers were folded. The binder systems in these formulations were different combinations of a styrene-butadiene latex and mixtures of latex and starch for two different pigment volume concentrations (PVC). Both types of papers were coated with single and double layers. The folded area was scanned with a high-resolution scanner while the samples were kept at their folded angle. The scanned images were analyzed within a constant area. The crack areas were reported for different types of papers, binder system and PVC values. As PVC, starch content, and paper basis weight increased, the crack area increased. Double layer coated papers with high PVC and high starch content at the top layer had more cracks in comparison with a single layer coated paper, but when the PVC of the top layer was low, cracking area decreased. No measurable cracking was observed when the top layer was formulated with a 100% latex layer.

Effect of toughened polyamide-coated carbon fiber fabric on the mechanical performance and fracture toughness of CFRP

2021 ◽  
pp. 002199832199945
Author(s):  
Jong H Eun ◽  
Bo K Choi ◽  
Sun M Sung ◽  
Min S Kim ◽  
Joon S Lee
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Photoelectron Spectroscopy ◽  
Mechanical Performance ◽  
Epoxy Composites ◽  
Scanning Calorimetry ◽  
Internal Damage ◽  
Impact Tests ◽  
Flexural Tests ◽  
The Impact

In this study, carbon/epoxy composites were manufactured by coating with a polyamide at different weight percentages (5 wt.%, 10 wt.%, 15 wt.%, and 20 wt.%) to improve their impact resistance and fracture toughness. The chemical reaction between the polyamide and epoxy resin were examined by fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray photoelectron spectroscopy. The mechanical properties and fracture toughness of the carbon/epoxy composites were analyzed. The mechanical properties of the carbon/epoxy composites, such as transverse flexural tests, longitudinal flexural tests, and impact tests, were investigated. After the impact tests, an ultrasonic C-scan was performed to reveal the internal damage area. The interlaminar fracture toughness of the carbon/epoxy composites was measured using a mode I test. The critical energy release rates were increased by 77% compared to the virgin carbon/epoxy composites. The surface morphology of the fractured surface was observed. The toughening mechanism of the carbon/epoxy composites was suggested based on the confirmed experimental data.

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