A Repair Alternative for Worn Square-Base Compressor Vanes

2004 ◽  
Author(s):  
Rodger O. Anderson ◽  
Fred T. Willett
Keyword(s):  
Gas Turbines ◽  
Field Experience ◽  
Root Cause ◽  
Sliding Motion ◽  
Alternative Approach ◽  
The World ◽  
Industrial Gas Turbines ◽  
Classic Solution ◽  
Over Time

Square base compressor vanes are a simple time-tested design and are in use in hundreds of large industrial gas turbines throughout the world. The square base of the vane fits inside a carrier slot machined into the compressor casing. Over time, the motion of the vane base, during operation and due to start-stop cycles, results in wear of both the vane base and the compressor casing. The classic solution to this wear problem is vane replacement and extensive repair of the casing either by welding or remachining and adding a patch ring. The square base compressor vane design is described, along with exemplary evidence of the wear problem. An alternative to the expensive repair is presented. The alternative approach addresses the root cause of the wear, i.e., the sliding motion at the vane base–casing interface. The vane contact is modeled with and without the solution to show, analytically, the benefit of the alternative approach. Successful field experience is also presented and discussed.

scholarly journals Tworzenie wspólnego ciała, czyli o przetwarzaniu terenu wśród boliwijskich Moré

2021 ◽  
Author(s):  
Paweł Chyc
Keyword(s):  
Field Experience ◽  
Field Research ◽  
Narrative Structure ◽  
Analytical Form ◽  
Research Process ◽  
The Other ◽  
Language Family ◽  
The World ◽  
Over Time

The aim of this anthropological essay is to present the emotional and intellectual processes accompanying me over the years of field research among the Bolivian Moré, who belong to the Chapacura language family. The narrative structure is twofold: addressing both topics and issues that motivated me intellectually to do the research, and the attitudes of Moré themselves, as well as conceptual categories around which their narratives seem to focus. Some passages of this essay take a more analytical form, as I focus on the impor- tance of unpredictable events, the context, and the transformation of field experience over time during the research process. I conclude that both sides of the fieldwork encounter face the task of getting to know the Other. Each gets to know the Other in a particular way through conceptual categories and ways of acting that result from their current way of being in the world.

Environmental Performance of Industrial Gas Turbines

1974 ◽  
Author(s):  
R. H. Johnson ◽  
Colin Wilkes
Keyword(s):  
Air Pollution ◽  
Carbon Monoxide ◽  
Environmental Performance ◽  
Gas Turbines ◽  
Hydrocarbon Fuel ◽  
Industrial Society ◽  
Oxides Of Nitrogen ◽  
The World ◽  
Industrial Gas Turbines ◽  
Power Needs

At this point in time, everyone is “for the environment” and this is true the world world over because the atmosphere is shared by peoples of all nations. Air pollution from hydrocarbon fuel combustion, both worldwide and local, is discussed by reviewing known measurements of contaminants. Application of gas turbines by industry is one way to provide power needs for attaining and maintaining an industrial society. Environmental performance of industrial gas turbines with respect to exhaust emissions and environmental impact is presented for oxides of nitrogen, hydrocarbons, carbon monoxide, particulate matter and visible smoke. Results of recent abatement efforts are also presented together with estimates of potential improvements to show the place of the industrial combustion turbine in a world with growing concern for environmental improvement.

Flexible Spacers Compressor Stator Blades for Heavy Industrial Gas Turbines Model 7EA

2003 ◽  
Author(s):  
Steve Ingistov
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Field Experience ◽  
Axial Compressor ◽  
Heavy Duty ◽  
Combustion Gas ◽  
Mechanical Integrity ◽  
Industrial Gas Turbines ◽  
Last Stage

This paper describes efforts to upgrade the mechanical integrity of axial compressor stator blades. The blades under discussion are part of an axial compressor of a heavy duty industrial Combustion Gas Turbine (CGT) made by GE, frame No. 7, model EA. The axial compressor stator blades, in the later stages of compression, are kept in required position by spacers or shims shaped to match the root profile of the blades. These spacers/shims may be as thick as 1/4 of an inch and as thin as 1/32 of an inch. These spacers/shims tend to wiggle out of the slots and eventually liberate themselves from the stator. This paper introduces a proposed solution to minimize liberation of the spacer/shims by introduction of flexible spacers/shims. This paper also describes field experience with loss of the stator blades in the last stage of compression, due to aerodynamic disturbances.

Materials Keep Pace With Industrial Gas-Turbine Needs

1961 ◽  
Author(s):  
Harry B. Gayley
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Field Experience ◽  
Material Data ◽  
Disk Material ◽  
Data Field ◽  
Study Programs ◽  
Industrial Gas Turbines ◽  
Turbine Design ◽  
Industrial Gas Turbine

Reliability and improvements in industrial gas turbines are closely related to the materials study programs which are conducted in support of the turbine design. The studies at the author’s company are described with presentation of blade and disk material data. Field experience as related to materials evaluations are described, with particular emphasis on returning parts to service. Materials now available when fully evaluated, through the program described, will permit metal temperatures 100 degrees F higher than currently used.

Strategy for Selecting Optimised Technologies for Gas Turbine Air Inlet Filtration Systems

2011 ◽  
Author(s):  
Stephen D. Hiner
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Fuel Quality ◽  
Air Filtration ◽  
Air Inlet ◽  
Filtration System ◽  
The World ◽  
Maintenance Requirements ◽  
Specific Challenge ◽  
Over Time

With continuous advances in gas turbine technology, wider breadth of fuel quality burnt and ever growing expectations of; longer life, higher efficiency and reduced maintenance requirements, the filtration of the air entering the gas turbine (GT) has never been more important to meeting its operational requirements. Gas turbines are used throughout the world in an ever increasing diversity of application and environment. This presents a number of challenges to the air filtration system, that require unique solutions for each subset of environment specific challenge, gas turbine platform technology and fuel quality being burnt. This paper discusses the importance of air filtration to a modern GT and how this has changed over time and it’s shifting operational requirements. It explores the challenges facing the air filtration system presented by the different; environments, GT technologies and fuel quality. The paper details what approaches and filtration technologies are currently used to address these challenges, with strengths and weaknesses explained as appropriate, to finally present a strategy for specifying an optimized filtration system to meet the challenges of the modern GT.

Nozzle Cracking in Gas Turbines

2000 ◽  
Author(s):  
Manuchehr Shirmohamadi ◽  
Shawn Bratt ◽  
Difei Wang ◽  
Ahmad Ganji ◽  
Rob Neville
Keyword(s):  
Gas Turbines ◽  
Low Cycle Fatigue ◽  
Economic Costs ◽  
Root Cause ◽  
Cyclic Stresses ◽  
Primary Mechanism ◽  
Industrial Gas Turbines ◽  
Cracking Mechanisms ◽  
Original Equipment Manufacturers ◽  
Operating Cycles

Cracking of 1st stage nozzles occurs routinely in industrial gas turbines. Such cracking, which sometimes is observed after only a few operating cycles, leads to short intervals between overhauls and expensive repairs or replacements of the nozzle sections. Despite the enormous economic costs associated with nozzle cracking; mechanisms, root causes, and optimum mitigation of such cracking has not been convincingly determined. In fact, some original equipment manufacturers (OEM) consider nozzle cracking as a “fact of life” and have only issued recommendations for their monitoring and replacements. The objective of this work was to identify the mechanisms and the root causes for the 1st stage nozzle cracking of a Frame-3 gas turbine. In this project, we measured, monitored, modeled, and analyzed the temperature and stress response of the nozzles during actual operating practices. This work concluded that the primary mechanism of such cracking is low cycle fatigue caused by high cyclic stresses. The major source of these high stresses was determined to be related to thermal and pressure shocks caused by transonic events which occur during the unit startups. This work offers recommendations to mitigate such cracking and a testing program to verify the root cause.

Geoffrey Bertram Robert Feilden CBE. 20 February 1917 – 1 May 2004

2005 ◽  
Vol 51 ◽  
pp. 135-148
Author(s):  
Kelvin Bray ◽  
Alexander Moulton
Keyword(s):  
Gas Turbines ◽  
High Reliability ◽  
Prime Mover ◽  
Remote Operation ◽  
The World ◽  
Industrial Gas Turbines ◽  
Innovative Work ◽  
Scientists And Engineers

Bob Feilden will be remembered by scientists and engineers around the world for his innovative work on industrial gas turbines which became, in the Ruston Type TAgas turbine, a prime mover of choice for all those who wanted high reliability and automatic or remote operation.

Globalization and interconfessional communications

2001 ◽  
pp. 13-17
Author(s):  
Serhii Viktorovych Svystunov
Keyword(s):  
21St Century ◽  
Global Economy ◽  
Modern World ◽  
The World ◽  
Target Set ◽  
Almost All ◽  
Over Time ◽  
Rapid Appearance

In the 21st century, the world became a sign of globalization: global conflicts, global disasters, global economy, global Internet, etc. The Polish researcher Casimir Zhigulsky defines globalization as a kind of process, that is, the target set of characteristic changes that develop over time and occur in the modern world. These changes in general are reduced to mutual rapprochement, reduction of distances, the rapid appearance of a large number of different connections, contacts, exchanges, and to increase the dependence of society in almost all spheres of his life from what is happening in other, often very remote regions of the world.

The Values and Norms of Islam

2010 ◽  
Vol 1 (1) ◽  
pp. 1-19
Author(s):  
Ahmed Akgunduz
Keyword(s):  
Islamic Law ◽  
Legal Theory ◽  
The Other ◽  
Moral Norms ◽  
Simple Fact ◽  
Value System ◽  
Legal Norms ◽  
Islamic Legal Theory ◽  
The World ◽  
Over Time

AbstractIslamic Law is one of the broadest and most comprehensive systems of legislation in the world. It was applied, through various schools of thought, from one end of the Muslim world to the other. It also had a great impact on other nations and cultures. We will focus in this article on values and norms in Islamic law. The value system of Islam is immutable and does not tolerate change over time for the simple fact that human nature does not change. The basic values and needs (which can be called maṣlaḥa) are classified hierarchically into three levels: (1) necessities (Ḍarūriyyāt), (2) convenience (Ḥājiyyāt), and (3) refinements (Kamāliyyāt=Taḥsīniyyāt). In Islamic legal theory (Uṣūl al‐fiqh) the general aim of legislation is to realize values through protecting and guaranteeing their necessities (al-Ḍarūriyyāt) as well as stressing their importance (al‐ Ḥājiyyāt) and their refinements (taḥsīniyyāt).In the second part of this article we will draw attention to Islamic norms. Islam has paid great attention to norms that protect basic values. We cannot explain all the Islamic norms that relate to basic values, but we will classify them categorically. We will focus on four kinds of norms: 1) norms (rules) concerned with belief (I’tiqādiyyāt), 2) norms (rules) concerned with law (ʿAmaliyyāt); 3) general legal norms (Qawā‘id al‐ Kulliyya al‐Fiqhiyya); 4) norms (rules) concerned with ethics (Wijdāniyyāt = Aḵlāqiyyāt = Ādāb = social and moral norms).

Use of Phosphatidylcholine in the Treatment of Localized Fat Deposits. Results and expectations

2017 ◽  
Vol 68 (7) ◽  
pp. 1438-1441 ◽  
Author(s):  
Sorin Berbece ◽  
Dan Iliescu ◽  
Valeriu Ardeleanu ◽  
Alexandru Nicolau ◽  
Radu Cristian Jecan
Keyword(s):  
World Health Organisation ◽  
Normal Weight ◽  
World Health ◽  
Basic Substance ◽  
Physical Exercises ◽  
Fat Deposits ◽  
The World ◽  
The Common ◽  
Global Health Problem ◽  
Over Time

Obesity represents a global health problem. According to the latest studies released by the World Health Organisation (WHO), 1.7 billion currently in excess of normal weight individuals, of which approx. 75% are overweight (body mass index - BMI 25 to 30). The common form of excess adipose tissue manifestation in overweight individuals is localized fat deposits with high (abdominal) or low (buttocks and thighs) disposition. Although the overweight can be corrected relatively easy by changing behavioral habits or food, a constant physical exercises program or following a diet food are not accessible to all through the efforts of will, financial and time involved. Several methods have been studied and tested over time to eliminate more or less invasive fat deposits with varying efficacy and adverse effects. Chemical lipolysis using phosphatidylcholine as the basic substance was initially used in hypercholesterolemia and its complications and was rapidly adopted in mesotherapy techniques for the treatment of fat deposits. This study reveals the results obtained using Dermastabilon on a sample of 16 patients, the time allocated to treatment and discomfort being minimal, and rapid and notable results. There were no side effects.

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