The casing shape and construction details depend on whether it is a high pressure hp or low pressure lp casings. Schofield ge company schenectady, ny introduction the need to provide stateoftheart products for a diverse and everchanging market is the chal lenge facing steam turbinegenerator manufactur ers in the 90s. From our simulations it was obvious that the steam turbine tripped due to insufficient inlet oil pressure during the runup. Steam turbine a steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into useful mechanical work classification pressure compounded impulse turbine velocity compounded. Prior to supplying steam to the turbine, the steam supply pipelines have to be drained and heated up. To alleviate this pressure the dump valve begins to open and regulates the gland sealing steam system by dumping this excess pressure. It is an assembly which is used to prevent the leakage of steam, fluid or water between sliding or turning part of the machine elements. The turbine gland sealing system tgss prevents the escape of steam from the turbine shaft and casing penetrations and the glands of main steam stop and. Recent technologies for steam turbines fujielectric. Steam turbine blades look a bit like propeller blades but are made from highperformance alloys because the steam flowing past is hot, at high pressure, and traveling fast. Fire resisting fluid acknowledgements glossary bibliography biographical sketch summary steam turbines consist essentially of a casing to which stationary blades are fixed on the. Ethosenergy retractable seals provide a sealing system that have larger clearances during start up and shutdown drastically reducing the potential of a rub on the seals or bow in the rotor.
The steam turbines principle is that the steam energy is. Delivering cuttingedge turbine and generator technologies. A gland seal system can be as simple as a spray chamber, loop seal and a steam ejector or as complex as surface condensers, air blowers or vacuum pumps. While selecting a steam turbine as a driver for compressors or pumps for refinerypetrochemical industries. The steam turbine gland steam seal system is designed to keep steam from leaking out of the turbine and to prevent air from leaking into the turbine. Power systems as a steam turbine rotordy namicist, and six years at ge. Doosan delivering cuttingedge turbine and generator technologies 3. This cause was investigated in using 5 different scenarios. In a changing market where many steam turbines are moving away from base load into a cycling environment this is becoming more and more of a critical concern.
Steam program service evaluation for power generation. A shaft sealing system and method are disclosed for a high or intermediate pressure turbine section having a rotating member including a shaft and a stationary member surrounding the rotating member and defining a steam flow path. This masters thesis focuses on the design of steam condensate system of steam power plants. Gland sealing in steam turbines are labyrinth type seal, the objective is to seal the clearance between static and rotary part of turbine, in high pressure zone of turbine there is a tendency of high pressure steam leakage to the atmosphere and at. The condensing steam turbine is a conventional steam turbine in which the steam exiting the turbine exhaust is condensed to provide the maximum energy capture. Latest technologies and future prospects for a new steam. Differential expansion of steam turbine generators by chris james skf reliability systems turbine supervisory instrumentation modern vibration monitoring instrumentation systems are also specifically designed to perform critical measurements which are used in the control of large steam turbine generator trains. Nov 19, 2016 function of gland steaming in turbine operation. Three basic types of steam turbine are used to generate power as a byproduct of process or exhaust steamml. Overlooked gland seal can be big trouble power services.
Types of steam turbine an overview sciencedirect topics. Gland steam must have appropriate temperature and pressure which must be controlled during startup. Latest technologies and future prospects for a new steam turbine. In the efficient use of energy second edition, 1982. How does the steam turbine gland sealing system work. The steam turbines are widely used in power generation, refineries and petrochemical industries. Gland steam sealing system for steam turbine youtube. The shaft sealing system comprises at least one seal disposed about each of a first end and a second end of the. In a multistage steam turbine having a first rotating member including a shaft, a second stationary member surrounding said first member and defining a steam flow path having a highpressure inlet at one end of the turbine and a lowpressure outlet at its opposite end, a shaft sealing system adjacent the inlet and outlet ends of said turbine, comprising. Steam turbines for industrial applications ge power systems ger3706d 3 geared turbine generator sets complete packages can include turbine, gear, oil system and generator for quick installation turbine speeds selected to optimize lifecycle costs 15001800 rpm, 4pole generators for 5060 hz applications applications to. Harmonization of product lines the enhanced platform steam turbine design combines the advantages of all the established siemens industrial steam turbine product lines. As turbine exhaust is connected to a condenser which is operated below atm pressure so there are chances of air ingres or va.
An improved sealing system allows more sealing strips per blade row for both moving and stationary. In this article, we will discuss steam turbine basic parts. Steam turbine gland seal is a major constituent element of a turbine, which has a direct bearing on the steam leakage of a turbine seal, and thus affects the thermal efficiency of a steam turbine. Also small amounts of condensate form in steam pipelines due to radiation heat loss. The reason for these specific scenarios was to determine the impact that each of these components sealing surface would have on the oil pressure. A gland seal system can be as simple as a spray chamber, loop seal and a steam ejector or as complex as. The first question faced by the design engineer is which standard steam turbine as to be selected either api 611 or api 612. The dry gas may be air such as dehydrated instrument air, or. In its simplest form, a steam turbine consist of a boiler steam generator, turbine, condenser, feed pump and a variety of auxiliary devices.
Overlooked gland seal can be big trouble power services group. During startup and lowload operation, the sealing steam distribution header has two sources of steam supply. Major milestone of doosan steam turbine 1904 first steam turbine system rateau skoda works czech. Dec 03, 2015 the steam turbine gland steam seal system is designed to keep steam from leaking out of the turbine and to prevent air from leaking into the turbine.
To sealing turbine before pulling condensate vacumn before start up, gland sealing steam is extracted from the live steam system or auxiliary steam systeam and decreased both pressure and temperature pressure. Thats one reason why steam turbines were quickly adopted for powering ships, where space was very limited. The shaft sealing system comprises at least one seal disposed about each of a first end and a second end of the shaft. This is important, for if the low pressure end is primarily sealed with the high pressure end seal leaking off steam, exhaust end packings may not get much. The sst compact turbogenerator serves a range of upto kw is designed to expand natural gas in pressure regulating stations as a direct driving turbine in pipe installation. The normal sealing steam pressure of a condensing turbine is about 34 psig.
In general, a steam turbine is a rotary heat engine that converts thermal energy contained in the steam to mechanical energy or to electrical energy. A gland sealing steam supply system according to claim 6, wherein said system further includes a gas turbine, and a waste heat recovey boiler used for recovering heat of a waste gas from said gas turbine and having a highpressure steam generating portion consisting of an economizer, a highpressure steam generator and a superheater, and a low. With a gas turbine the quantity of fuel fed is closedloop controlled e. Most industrial installations are in the range 15 mw e. Nov 25, 2019 a steam turbine is also much more compact than a steam engine. General electric systems technology manual chapter 2. Water contamination of steam turbine lube oilshow to avoid it 53 in the writers opinion, the best way of coping with this problem is to install a dry gas purge at the bearing housing seals. These are manufactured for outputs from 50 kw e to 30 mw e. Kwu turbine sealing ring what is the full form of a. To provide over pressure protection for the reactor vessel and reactor coolant system.
Shaft sealing of steam turbines general electric company. The sealing system also prevents the air from going inside the turbine when the exhaust casing is under vacuum this is particular for condensing type steam. Dec 18, 2015 place the gland sealing steam system in service. Temperatures of about 1,000 degrees fahrenheit and pressures of about 3,500 pounds per square inch is reached by steam. Main oil pump to be opened bearing, sealing rings, rotor, impeller etc, to be checked.
Simultaneously, gland steam system is started to prevent air inleakage. For low and moderate inlet steam pressure up to 120 bar, a single shell. Ger3705 ge steam turbine design philosophy and technology. 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. Complete governing system and protection equipment to be cleaned and checked. This dumped gland sealing steam and any leak off steam from the lower pressure glands is not wasted but piped under. A typical turbine governing system has two unloaders one activated by low condenservacuum. Labyrinth packing an overview sciencedirect topics. Turbine is turned by steam turbine shaft turns due to high pressure of steam pushing against series of giant turbine blades.
This is the type of steam turbine that will be used in a bottoming cycle chp plant in which waste heat or energy from an industrial process is used to raise steam to generate electricity. The gland sealing steam system provides lowpressure steam to the turbine gland in the final sets of labyrinth packing. Steam turbine basic parts mechanical engineering site. In case of turbines with cooling water preheating and lowpressure lp. Unlike with reciprocating engines, for instance, compression, heating and expansion are.
Pdf simulation of speed steam turbine control system. A higher sealing steam pressure is recommended at the outset to assist the outboard seals to begin breakin. What is steam turbine description and characteristics. Steam turbine advanced sealing system mda turbines. Information technology means it is related to computers. Function and system layout the two functions of the turbine glands and seals are. Hydraulic control systems in gas and steam turbines. For understanding the gland sealing system first we have to understand why it is required so there are two main reason. Ger3706d steam turbines for industrial applications. C61207 this standard specifies the minimum requirements for. Pengantar fungsi utama gland sealing mengurangi kebocoran uap, khususnya pada celah shaft mengurangi intrusi udara ke dalam. Condensate is generated when fractions of extracted steam from the turbine transfer heat to feedwater in the feedwater heaters. All steam turbines have the same basic parts, though theres a lot of variation in how theyre arranged. They can be used like a low pressure body of a two casing turbine, or like a stand alone turbine for low pressure steam conditions.
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