Magnetic Particle Inspection of Turbine Blades in Power Generating Plants

1992 ◽  
Author(s):  
Clement Imbert ◽  
Krishna Rampersad
Keyword(s):  
Preventive Maintenance ◽  
Gas Turbines ◽  
Power Plants ◽  
Magnetic Particle ◽  
Martensitic Stainless Steel ◽  
Turbine Blades ◽  
Magnetic Particle Inspection ◽  
Optimum Placement ◽  
Non Destructive ◽  
Defect Detectability

Modern societies expect and depend on regular, relatively uninterrupted, supply of electric power. Preventive maintenance is therefore vital for power generating plants. Non-Destructive Evaluation (NDE) is a significant element of the maintenance programme of power plants. Power plants use a wide variety of steam and gas turbines. Turbine failure can occur without warning and with disastrous results. Such failures are invariably caused by cracks. Such defects are readily detected by NDE techniques such as Magnetic Particle Inspection (MPI) if they are on or near the surface and accessible. This paper reports on the use of MPI in the examination of martensitic stainless steel turbine blades in power plants in Trinidad and Tobago so as to quantify the testing parameters and determine field strength in relation to defect detectability. Specific recommendations are made regarding the configuration and optimum placement of magnetizing coils for turbine blade inspection insitu and detached.

scholarly journals Effect of Temperature and Hold Time of Induction Brazing on Microstructure and Shear Strength of Martensitic Stainless Steel Joints

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1586 ◽  
Author(s):  
Yunxia Chen ◽  
Haichao Cui
Keyword(s):  
Stainless Steel ◽  
Shear Strength ◽  
Power Plants ◽  
Filler Metal ◽  
Martensitic Stainless Steel ◽  
Braze Alloy ◽  
Hold Time ◽  
Turbine Blades ◽  
Element Distribution ◽  
Effect Of Temperature

1Cr12Mo martensitic stainless steel is widely used for intermediate and low-pressure steam turbine blades in fossil-fuel power plants. A nickel-based filler metal (SFA-5.8 BNi-2) was used to braze 1Cr12Mo in an Ar atmosphere. The influence of brazing temperature and hold time on the joints was studied. Microstructure of the joints brazed, element distribution and shear stress were evaluated at different brazing temperatures, ranging from 1050 °C to 1120 °C, with holding times of 10 s, 30 s, 50 s and 90 s. The results show that brazing joints mainly consist of the matrix of the braze alloy, the precipitation, and the diffusion affected zone. The filler metal elements diffusion is more active with increased brazing temperature and prolonged hold time. The shear strength of the brazed joints is greater than 250 MPa when the brazing temperature is 1080 °C and the hold time is 30 s.

New Developments in High Temperature Materials 21 Project in Japan

2005 ◽  
Author(s):  
Hiroshi Harada ◽  
Junzo Fujioka
Keyword(s):  
High Temperature ◽  
Thermal Efficiency ◽  
Gas Turbines ◽  
Power Plants ◽  
Turbine Blades ◽  
Combined Cycle ◽  
Jet Engines ◽  
High Temperature Materials ◽  
Design Program ◽  
Temperature Capability

Following the Kyoto Conference on Climate Change (COP3) held in 1997, the improvement of thermal efficiency in power engineering systems is becoming a major issue. In High Temperature Materials 21 Project at NIMS, materials for turbine blades and vanes are being developed to improve the temperature capability and reduce the CO2 emission of industrial gas turbines (IGT) and jet engines. The target for Ni-base superalloys was set at 1100°C for 1000h creep rupture life under 137MPa to realize ultra-efficient combined cycle power plants and advanced jet engines. A high cost-performance single crystal (SC) superalloy TMS-82+ with 1075°C temperature capability has been developed and tested in a 15MW IGT. A 4th generation SC superalloy TMS-138 exhibiting 1080°C temperature capability has also been developed and tested in a 1650°C test jet engine. TMS-138 is to be applied in the Japanese eco-engine project for 50-seater jet airplanes. A further control of the interfacial dislocation network resulted in a 5th generation SC alloy TMS-162 with 1105°C temperature capability. A virtual gas turbine (VT), which is a combination of materials design program and system design program, is being developed and becoming a powerful tool as an interface between material scientists and system engineers. Using VT, air-cooled blades with our SC superalloys have been evaluated up to 1700°C gas temperature, and a substantial improvement in thermal efficiency of a combined-cycle power generation system has been indicated.

Development and Implementation of Repair Processes for Refurbishment of W501F, Row 1 Turbine Blades

2001 ◽  
Author(s):  
Richard Curtis ◽  
Warren Miglietti ◽  
Michael Pelle
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Power Plants ◽  
High Efficiency ◽  
Turbine Blades ◽  
Combined Cycle ◽  
Cycle Basis ◽  
Repair Procedure ◽  
Crack Repair ◽  
Maintenance Requirements

In recent years, orders for new land-based gas turbines have skyrocketed, as the planning, construction and commissioning of new power plants based on combined-cycle technology advances at an unprecedented pace. It is estimated that 65–70% of these new equipment orders is for high-efficiency, advanced “F”, “G” or “H” class machines. The W501F/FC/FD gas turbine, an “F” class machine currently rated at 186.5 MW (simple cycle basis), has entered service in significant numbers. It is therefore of prime interest to owners/operators of this gas turbine to have sound component refurbishment capabilities available to support maintenance requirements. Processes to refurbish the Row 1 turbine blade, arguably the highest “frequency of replacement” component in the combustion and hot sections of the turbine, were recently developed. Procedures developed include removal of brazed tip plates, coating removal, rejuvenation heat treatment, full tip replacement utilizing electron beam (EB) and automated micro-plasma transferred arc (PTA), joining methods, proprietary platform crack repair and re-coating. This paper describes repair procedure development and implementation for each stage of the process, and documents the metallurgical and mechanical characteristics of the repaired regions of the component.

scholarly journals Effects of Damaged Rotor Blades on the Aerodynamic Behavior and Heat-Transfer Characteristics of High-Pressure Gas Turbines

Mathematics ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 627
Author(s):  
Thanh Dam Mai ◽  
Jaiyoung Ryu
Keyword(s):  
Heat Transfer ◽  
High Pressure ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Rotor Blade ◽  
High Speed ◽  
Power Plants ◽  
Thermal Stresses ◽  
Turbine Blades ◽  
Combined Cycle

Gas turbines are critical components of combined-cycle power plants because they influence the power output and overall efficiency. However, gas-turbine blades are susceptible to damage when operated under high-pressure, high-temperature conditions. This reduces gas-turbine performance and increases the probability of power-plant failure. This study compares the effects of rotor-blade damage at different locations on their aerodynamic behavior and heat-transfer properties. To this end, we considered five cases: a reference case involving a normal rotor blade and one case each of damage occurring on the pressure and suction sides of the blades’ near-tip and midspan sections. We used the Reynolds-averaged Navier-Stokes equation coupled with the k − ω SST γ turbulence model to solve the problem of high-speed, high-pressure compressible flow through the GE-E3 gas-turbine model. The results reveal that the rotor-blade damage increases the heat-transfer coefficients of the blade and vane surfaces by approximately 1% and 0.5%, respectively. This, in turn, increases their thermal stresses, especially near the rotor-blade tip and around damaged locations. The four damaged-blade cases reveal an increase in the aerodynamic force acting on the blade/vane surfaces. This increases the mechanical stress on and reduces the fatigue life of the blade/vane components.

scholarly journals Transpiration Air Protected Turbine Blades: An Effective Concept to Achieve High Temperature and Erosion Resistance for Gas Turbines Operating in an Aggressive Environment

1978 ◽  
Author(s):  
R. Raj ◽  
S. L. Moskowitz
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Power Plants ◽  
Erosion Resistance ◽  
Turbine Blades ◽  
Future Generation ◽  
Combined Cycle ◽  
Gaseous Fuels ◽  
Cooled Blade

The future generation is looking forward to the use of gas turbine inlet temperatures as high as 3000 F (1650 C) with attendant thermal efficiencies of from 40 to 50 percent in combined cycle electric power plants. In addition to the use of high temperature for improved efficiency, the national needs, due to scarcity of oil and natural gas, will heavily stress the use of coal as a fuel. The particulate from combustion of coal derived liquid and gaseous fuels, even after employing hot gas cleanup systems, may damage conventional turbine blades and thus reduce turbine life. This paper is intended to show how a transpiration-cooled blade can cope with both of the foregoing problems simultaneously. The fundamental aspects of the transpiration-cooled blade technology will also be explained. Experimental results using this design concept indicate that significant erosion resistance is feasible for gas turbine blading in the near future.

Advanced Particle Control for Coal-Based Power Generation Systems

1989 ◽  
Author(s):  
Steven J. Bossart
Keyword(s):  
Power Generation ◽  
Gas Turbine ◽  
Gas Turbines ◽  
High Speed ◽  
Particle Deposition ◽  
Power Plants ◽  
Turbine Blades ◽  
Combined Cycle ◽  
Department Of Energy ◽  
Power Generation Systems

The Morgantown Energy Technology Center (METC) of the U.S. Department of Energy (DOE) is actively sponsoring research to develop coal-based power generation systems that use coal more efficiently and economically and with lower emissions than conventional pulverized-coal power plants. Some of the more promising of the advanced coal-based power generation systems are shown in Figure 1: pressurized fluidized-bed combustion combined-cycle (PFBC), integrated gasification combined-cycle (IGCC), and direct coal-fueled turbine (DCFT). These systems rely on gas turbines to produce all or a portion of the electrical power generation. An essential feature of each of these systems is the control of particles at high-temperature and high-pressure (HTHP) conditions. Particle control is needed in all advanced power generation systems to meet environmental regulations and to protect the gas turbine and other major system components. Particles can play a significant role in damaging the gas turbine by erosion, deposition, and corrosion. Erosion is caused by the high-speed impaction of particles on the turbine blades. Particle deposition on the turbine blades can impede gas flow and block cooling air. Particle deposition also contributes to corrosive attack when alkali metal compounds adsorbed on the particles react with the gas turbine blades. Incorporation of HTHP particle control technologies into the advanced power generation systems can reduce gas turbine maintenance requirements, increase plant efficiency, reduce plant capital cost, lower the cost of electricity, reduce wastewater treatment requirements, and eliminate the need for post-turbine particle control to meet New Source Performance Standards (NSPS) for particle emissions.

Successful Power Limit Increase Testing of SGT5/6-2000E Gas Turbines on the Basis of Si3D Turbine Blading

2014 ◽  
Author(s):  
Martin G. Stapper ◽  
Simon I. Kliesch ◽  
David P. Holzapfel
Keyword(s):  
Mass Flow ◽  
Power Output ◽  
Gas Turbines ◽  
Power Plants ◽  
Essential Feature ◽  
Turbine Blades ◽  
Ambient Temperatures ◽  
Higher Power ◽  
Power Limit ◽  
Turbine Blading

One of the most innovative solutions for making SGTx-2000E gas turbines more competitive and more cost-effective is the Si3D upgrade product. The profile of the Si3D turbine blades and vanes is aerodynamically optimized. Based on this new Si3D design optimization, a Power Limit Increase (PLI) upgrade was developed in close cooperation with customers. The Power Limit Increase upgrade is a change of the engines rating which allows operating the engine at a higher maximum electrical power output. The PLI not only shows a much higher power output of up to 16 % but also a significant increase in efficiency at low ambient temperatures — especially for district heating power plants. In 2011/2012 at a Finnish SGT5-2000E an opportunity arose to carry out an extensive program of measurements for testing and validating how the power limit can be increased in parallel with the blading upgrade (no compressor modification). The essential feature of this campaign was a non-intrusive stress measurement of blade vibration by means of optical probes. The campaign was successfully completed, and the Finnish customer is able to take advantage of optimized winter operation. The main benefit is operation of the engine at base load, especially at very low ambient temperatures with a higher power output and efficiency potential. On the basis of these encouraging results, Siemens prepared a fleet release for a power limit increase of all SGT5-2000E gas turbines with Si3D airfoils in stages 1 to 4 from 173 MW to 186 MW (with compressor mass flow increase) or even up to 196.5 MW. In addition, a second opportunity arose 2013 to execute the similar test campaign in the USA for the 60 Hz Si3D turbine blading with a compressor mass flow increase. Thereby not only the same test equipment was used, but several additional investigations had to be done prior to the test campaign. This publication describes details of the technical evaluation and conversions required to perform these tests and accomplish an increase of the power limit of the SGTx-2000E fleet.

scholarly journals Experimental Evaluation of the Effects of Structural Changes on the Vibration Properties of CK35 Steel

2021 ◽  
Vol 15 (2) ◽  
pp. 53-57
Author(s):  
Navid Moshtaghi Yazani
Keyword(s):  
Power Plants ◽  
Structural Changes ◽  
Natural Frequencies ◽  
Turbine Blades ◽  
Damping Coefficient ◽  
Jet Engines ◽  
Modal Test ◽  
Long Run ◽  
Ferrite Structure ◽  
Non Destructive

Abstract The microstructure of some components which operate in high-temperature conditions (e.g. boiler components, turbine blades used in gas power plants, jet engines and reactors) is subjected to changes in long run, which leads to a degradation in the mechanical properties of these components and consequently, reduces their lifecycle. Therefore, it is so useful to detect the changes in the microstructure of these parts during their operation, employing an easy, fast and non-destructive method to determine their remaining life. In this study, we evaluate the effects of the microstructural changes on natural frequencies and the damping coefficient of CK35 steel, employing the experimental modal test. We aim to use the method for power plant components, if it has significant effects. To do so, we applied spheroidization heat treatment on CK35 steel samples having a primary structure of ferrite-pearlite for 24 and 48 hours. Then, we carried out the experimental modal test on samples having different metallurgical structures, but with the same dimensions and weights. According to the findings, the spherical ferrite-carbide particles in the ferrite structure increase the natural frequencies and damping coefficient. These tests show that the structural changes in this type of steel result in slight changes in the values of natural frequencies; however, it significantly changes the damping frequencies.

Advanced Blading for Last Stages of Heavy Duty Gas Turbines: A Joint German Action

1992 ◽  
Author(s):  
U. Pickert ◽  
K. H. Keienburg ◽  
R. Bürgel ◽  
K. Schneider
Keyword(s):  
Gas Turbines ◽  
Turbine Blades ◽  
Current Status ◽  
Destructive Testing ◽  
Gas Turbine Blades ◽  
Material Component ◽  
Property Data ◽  
Static And Dynamic Loads ◽  
Component Property ◽  
Non Destructive

Large stationary gas turbine blades are highly stressed by static and dynamic loads. In 1986, ABB and Siemens/KWU initiated an R&D-program to develop large blades of Ni-base superalloys with higher operating capability. The aim of the program is to develop with main suppliers new manufacturing routes and non-destructive testing methods for measuring residual stresses as well as to generate with institutes the relevant material/component property data. So far — scheduled end of the program in mid 1993 — new manufacturing routes are established which allow a higher stressing of blades. The current status and future outlook will be highlighted.

scholarly journals Development of a new type of automatic magnetic particle inspection wall-climbing robot

2021 ◽  
Vol 13 (9) ◽  
pp. 168781402110473
Author(s):  
Jun Liu ◽  
Hanlin Yu ◽  
Linbo Mei ◽  
Bo Han
Keyword(s):  
Steam Turbine ◽  
Crack Detection ◽  
Magnetic Particle ◽  
Turbine Blades ◽  
Simulation Software ◽  
The Body ◽  
Working Environment ◽  
Climbing Robot ◽  
Magnetic Particle Inspection ◽  
Steam Turbine Blades

In the paper, a permanent magnet adsorption wall-climbing robot using magnetic particle detection technology for crack detection is introduced, which solves the problems of low efficiency of traditional manual detection and long detection time. According to the working environment of the detection system and the detection functions that need to be completed, the body structure of the robot is designed, the overall size of the robot is smaller than the distance between two steam turbine blades, so it can achieve the crack detection function of large steam turbine blades, and the stability and force analysis of the robot are carried out, and the adsorption conditions that meet the conditions of no sliding and overturning are obtained. In the paper, we use the magnetic circuit method to design a miniature excitation device for robotic applications and use the simulation software Ansoft-Maxwell to verify its feasibility. In the final experiment, it can be shown that the robot designed can achieve a series of functions such as magnetic particle inspection and image acquisition. There is a good prospect for the inspection of turbine blades.

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