When turbine is in service, superheated steam temperature above 540 degree celsius is admitted into the turbine. If one foot is stuck, an excessive differential reading ab will be observed between the sides. We are commissioning this turbine for the first time. These include the speed, vibrations, axial position and differential expansion of the turbo set. Thermal expansion of the shaft would be in an axial direction away from the. Steam turbine component characteristics, failure mechanisms, arrangements and applications steam turbines are fundamentally the same regardless of whether they drive a simple 500 shaft. To prevent rubbingtlamage, the axial differential expansion ofeach. Improvements of up to 30% were accounted to this measure. Nuclear and coal based thermal power plants together produce almost half of the worlds power. Steam turbines are one of the most versatile and oldest prime mover technologies still in general production used to drive a generator or mechanical machinery. Notes references module 2348 the turbine supervisory system. Rotor expansion with respect to the casing is differential expansion. Free ebooks gas turbine theory download free download gas turbine theory ebooks pdf download gas turbine theory ebooks pdf no wonder you activities are, reading will be always needed. This measurement is typically performed on larger steam.
A sleeve surrounds the distal part of the first rod on an. Print and download free steam turbine bingo cards or make custom steam turbine bingo cards. Reliability analysis for differential expansion of steam. Differential expansion is the difference between the thermal growth of the rotor and the thermal growth of the turbine case. Us8882449b2 innertoouter shell differential expansion. A common steam turbine has a thick, heavy, that is used to measure the thermal expansion of a steam turbine shell casing relative to the. Turbine supervisory instrumentation system which supervises turbine with the help of instruments. The measurement is commonly referred to as differential expansion and applies to various stages of. Vibration monitoring system for steam turbine turbine. Buzzbuzzbingo create, download, print, play, bingo. A consequence of excessive thermal expansion is rotor rubbing. The coefficient of thermal expansion is also often defined as the fractional increase in length per unit rise in temperature.
Print 2 pages of steam turbine bingo cards for free. A shell differential expansion detector and turbomachine including a detector are disclosed. The function of the steam turbine generator is to convert the thermal energy of the steam from the steam generator to electrical energy. The flow of steam through nozzles may be regarded as adiabatic expansion. The results from both calculations will be compared in order to determine if the ideal gas model leads to valid results. Request pdf differential expansion sensitivity studies during steam turbine startup in order to improve the startup flexibility of steam turbines, it becomes relevant to analyze their dynamic. Taking into consideration thermal expansion and dilatation measured from photogrammetry it is observed that the. Download a pdf with 2 free pages of bingo cards plus instructions and a randomized call sheet. Turbine efficiency is the ratio of actual work output of the turbine to the net input energy. A typical large steam turbine power generation unit will have a thick case, on the. Differential expansion measurements on large steam turbines one of the challenges facing instrumentation engineers in the power generation sector is the accurate measurement of shaft growth relative to casing on large steam turbines. Gas turbine combined cycle power plants 1st edition s. Purchase more randomly generated bingo card pages below. He showed that through the use of expansion turbines at city gates it is possible to.
The first rod further includes a proximal part within the housing. The primary purpose of a differential expansion monitor is to guard against axial rub between rotating and stationary parts. There are three primary areas in which temper ature response of the turbine components affect turbine operation. Casing expansion with respect to turbines foundation. Article pdf available in journal of engineering for gas turbines and power 1402 august 2017 with 408 reads. An increase in differential expansion may be caused by too fast a change in inlet steam temperature or due to too rapid change in steam flow to the turbine. Both the ends are supported on independent pedestals. Turbine supervisory instrumentation system tsi on large steam turbine generator applications. This system offers a high poweroutput by a very smallsized turbine. Steam turbine bingo cards to download, print and customize. Play steam turbine bingo in a browser or customize the events, free space, etc. Turbine gas expansion turbine turbinegenerator generator.
Generally in a steam turbine the rear support of the steam turbine or the rear side of the casing is fixed. In an embodiment, the shell differential expansion detector device includes a housing. Although the application of differential expansion and rotor expansion have much in common, it is important to understand the difference between the two measurements. Bhatia, in advanced renewable energy systems, 2014. Differential expansion sensitivity studies during steam.
Differential expansion on a turbine is the relative. Each time it starts, the turbine after rolling about 2 or 3 hours differential expansion reach to its limit 1mm, and turbine trips, we have scyncronizing and reaching to 20mw during this 3 houres. Steam turbine casing front side is generally free and slide on the front side bearing pedestal. Steam turbines startups 1 principles of steam turbines startups. Pdf integrated approach for steam turbine thermostructural. As seen in figure 5, the turbine generator was aligned in cold condition. Anchor point is always located near high temperature end to minimize the differential expansion. The case expansion measurement typically uses two lvdts one on each sliding foot to ensures that the case is growing equally on each side.
Turbine loading leads to positive expansion, while unloading results in negative differential. Hence, it is necessary to maintain the highpressure turbine hpt, intermediatepressure turbine ipt, and lowpressure turbine lpt differential expansions within the predetermined limits. Ifthe difference is ex cessive, some axial clearances inside the turbine can close. Steam turbines lie at the heart of these power plants. Gas turbine expansion joint profile cold to cold flange configuration. Turbine efficiency is a strong function of the blade speed ratio vtct0 and a weak function of pressure ratio, usually with high efficiency located at a large pressure ratio and a high flow rate. The expansion joint 100 includes a flange attached to a turbine duct 120 and a plurality of plates 170 attached to the exhaust duct 140 and extending toward the flange. The real values of critical speeds should be measured at. Friction exists between the steam and the sides of the nozzle. Therefore, the expansion will be calculated using an ideal gas model and a real gas one. Maintenance and overhaul of steam turbines wgp42 05. Steam turbine differential expansion amp maintenance forums. In the case of excessive differential expansion, metaltometal contact may occur.
Differential expansion sensitivity studies during steam turbine startup article in journal of engineering for gas turbines and power 86 september 2015 with 437 reads how we measure reads. Based on the premise that the probability distribution of random parameters has been known, the differential expansion of steam turbine is analyzed by saddlepoint. Pdf use of expansion turbines in natural gas pressure. More details on the turbine research project pyrotak. Request pdf differential expansion sensitivity studies during steam turbine startup in order to improve the startup flexibility of steam turbines, it becomes. The highpressure and intermediatepressure turbines are usually on a single shaft, driving a single.
Rotor expansion with respect to turbines foundation. The casing temperatures and rotorstator differential expansion, measured. It is not only to fulfil the duties that you need to finish in deadline time. A turboexpander, also referred to as a turboexpander or an expansion turbine, is a centrifugal or axialflow turbine, through which a highpressure gas is expanded to produce work that is often used to drive a compressor or generator because work is extracted from the expanding highpressure gas, the expansion is approximated by an isentropic process i. However below, similar to you visit this web page, it will be so enormously simple to get as capably as download guide kwu turbine manual. Can gulen phd 1992, rensselaer polytechnic institute, troy, ny, pe, asme fellow, has 25 years of mechanical engineering experience covering a wide spectrum of technology, system, and software design, development gtpromaster, thermoflex, assessment, and analysis, primarily in the field of steam and gas turbine combined cycle 109fbss, igcc 207fb, hsystem process and power plant. Turbine efficiency an overview sciencedirect topics.
Unesco eolss sample chapters thermal power plants steam turbine components and systems r. The pyrotechnic ignited, indirect turbine drive with reduction gearing is used for the pyrotak emergency door system. Differential expansion sensitivity studies during steam turbine. The engine extracts chemical energy from fuel and converts it to mechanical energy using the gaseous energy of the working fluid air to drive the engine and propeller, which, in turn, propel the airplane. Differentialrotor expansion sti vibration monitoring inc. Dec 18, 2015 impulse steam turbineimpulse steam turbine on impulse turbine a thermal expansion take place only in theon impulse turbine a thermal expansion take place only in the nozzles and static energy is converted to the kinetic energynozzles and static energy is converted to the kinetic energy there is no pressure different at inlet and outlet of. Steam turbines are being started based on operating instructions developed by turbine manufacturers and constituting an integral part of startup instructions of a steam unit. The plate 170 and the flange include a gap 210 between them, the gap 210. The exact definition varies, depending on whether it is specified at a precise temperature true coefficient of thermal expansion or or over a temperature range mean coefficient of thermal expansion or.
The steamhas a very high velocity at the end of the expansion, and the enthalpy decreases as expansion takes place. Jaroslav, 2004 2 analysed the performance of expansion turbine in natural gas pressure reduction stations. Gas turbine exhaust expansion joints, diverter and damper. Monitoring differential expansion is critical during a turbine cold startup. Differential expansion the change in axial clearances between the machine rotor and casing caused by thermal changes. Vibration monitoring system for steam turbine free download as powerpoint presentation.
Differential expansion on a turbine is the relative measurement of the rotors axial thermal growth with respect to the case. Intermediatepressure turbine an overview sciencedirect topics. To avoid differential expansion at the connecting flanges for example, it is recommended that compatible materials be used for these areas to prevent inducing. Tutbineaxial differential expansion iscoveredinmodule 23411. Sensonics technical note ds1220 differential expansion. Fundamentals of gas turbine engines introduction the gas turbine is an internal combustion engine that uses air as the working fluid. The reliability analysis for differential expansion of steam turbine is discussed extensively. The operating instructions describe the order of executing startup actions and provide the values of operating parameters that should be maintained during startups. Chaplin encyclopedia of life support systems eolss both of these have double casings with the exhaust steam circulating in the annular space between the casings as in the case of the high pressure turbine. Differential expansion monitoring measures the change in axial clearances between the machine rotor and casing caused by thermal changes inherent in most machines. Due to the varying temperature gradients during startup, the speed at which the turbine can start is constrained by thermal stresses and differential expansion. Severe problems encountered in gas turbine applications for the subject equipment are mostly traceable to stress buckling caused by differential expansion of components, improper insulation, unsuitable or incompatible mechanical design of features. Turbine lifting oil and jacking oil pumps in service tg engaging sequence engaging solenoid valve will be on. Above 600 rpm rotor relative vibrations should be monitored.
Steam turbine thermal modeling for improved transient. The studies performed serve as a base towards further understanding the differential expansion during start and establishing future clearance control strategies during turbine transient operation. In order to improve the startup flexibility of steam turbines, it becomes relevant to analyze their dynamic thermal behavior. What is differential casing expansion in steam turbine.
An expansion joint 100 for use between a turbine duct 120 and an exhaust duct 140 is provided. The exact definition varies, depending on whether it is specified at a precise temperature true coefficient of thermal expansion or or over a temperature range. Impulse steam turbineimpulse steam turbine on impulse turbine a thermal expansion take place only in theon impulse turbine a thermal expansion take place only in the nozzles and static energy is converted to the kinetic energynozzles and static energy is converted to the kinetic energy there is no pressure different at inlet and outlet of. The turbine supervisory instrumentation or tsi includes those measurements which monitor the behavior of the rotor train assembly.
One the threshold is exceeded, automatic trip of turbine takes place. What is differential or relative expansion in steam. Aug 04, 2018 heloo friends welcome to power plant guruji. Expansion joint hose flexible hose s h s d f s t ds straight line pipe battery limit line electronic serial heat trace side by side topbottom onetomany traced line multilines mid arrow multilines elbow ystrainer diverter valve ytype strainer rotary valve bursting disc expansion joint 2 pneumatic control pneumatic binary signal line. Rotor expansion on a turbine is the absolute measurement of the rotors axial thermal growth with respect to the turbines foundation. The ultimate state equation of differential expansion of steam turbine is proposed according to stressstrength interference theory.