Leakage solid particle erosion moisture erosion steam path deposits. Steam turbine blade and method for manufacturing same by akio sayano et al, kabushiki kaisha toshiba, issued december 17, 2009. However, bending can cause impact between stationary and. Hydraulic control systems in gas and steam turbines. The turbine glands are sealed with labyrinth packing when the exhaust steam is led to the vacuum condenser. A steam turbine package is made up of several components systems including the following. Steam turbine gland seal control system westinghouse. Jul 23, 2017 gland steam sealing system for steam turbine ap nam. Pdf simulation of speed steam turbine control system. To prevent air from entering into the turbine casing, sealing steam is led to the turbine glands.
Function and system layout the two functions of the turbine glands and seals are. As turbine exhaust is connected to a condenser which is operated below atm pressure so there are chances of air ingres or va. 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. A high pressure steam turbine having a sealing gland where the turbine rotor penetrates the casing of the turbine. The three areas covered in this guide are the main steam turbine, the steam seal system, and the lube oil system. Guardian packing rings can be installed in the hp, ip, lp turbine sections along with all gland seal areas in any steam turbine. Prior to supplying steam to the turbine, the steam supply pipelines have to be drained and heated up. Describes the control system for a steam turbine in a modern power plant. An industrial steam turbine experiences performance deterioration over time. Turbine shaft glands are sealed with auxiliary steam supplied by an electro hydraulically controlled seal steam pressure control valve. The gland sealing system is designed to supply steam to seal the turbine shaft glands at all operating conditions and to extract leakoff steam from the glands.
Turbine gland seal steam system free download as word doc. Us4793141a gland sealing steam supply system for steam. It also covers the related lube oil systems, instrumentation, control systems, and auxiliary equipment. A steam turbine gland seal control system for a steam turbine driving an electrical generator which supplies power to a load after main circuit breakers are closed, and in which the gland is self sealing by steam in the turbine after said closing, comprising. Boiler supply steam is used until there is sufficient pressure in the cold reheat circuit to supply the gland sealing steam. Unlike some packing designs, guardian packing rings maintain a positive radial seal during shutdown, turning gear, startup, and unit operation. Wagner, general electric company, issued may 11, 1982. Steam turbine rotors bend during operation, but the bearing and supports are designed to keep the static and dynamic forces under control. Find gland sealing system steam turbines related suppliers, manufacturers, products and specifications on globalspec a trusted source of gland sealing system steam turbines information. Turbine gland seal steam system turbine steam scribd. You face the ongoing need to enhance reliability, avoid unplanned outages, reduce maintenance costs and improve unit responsiveness not possible with your legacy system.
The gland sealing steam system provides lowpressure steam to the turbine gland. Simultaneously, gland steam system is started to prevent air inleakage. Gland steam sealing system for steam turbine ap nam. Fire resisting fluid acknowledgements glossary bibliography biographical sketch summary steam turbines consist essentially of a casing to which stationary blades are fixed on the. The tutorial is introduced by discussing the basics of steam turbine systems including the. A steam turbine gland seal control system for a steam turbine driving. Gland steam sealing system for steam turbine youtube. How does the steam turbine gland sealing system work. Dec 18, 2015 place the gland sealing steam system in service. The rate of the deterioration is influenced by the turbine design, the steam quality, and the way the turbine is operated. For understanding the gland sealing system first we have to understand why it is required so there are two main reason. Ger3705 ge steam turbine design philosophy and technology.
Ovation turbine control replacements include speed and load control, rotor stress and automatic turbine startup and sequencing as well as complete mechanical and hydraulic. Overlooked gland seal can be big trouble power services group. 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. The gland sealing steam system provides lowpressure steam to the turbine gland in the final sets of labyrinth packing. Basically, it is possible to equip the gas turbine with two fuel systems, namely natural gas and fuel oil. Thus for a gland with a given number of restrictions, there is an associated pressure ratio that produces the maximum leakage through the gland. This assists the labyrinth packing in sealing the turbine to prevent the entrance of air from reducing or destroying the vacuum in the associated condenser. I failed the gland sealing system test at my large steam turbine field engineering training, so ill have to go look at my manual to answer the rest of your questions.
Describe the main components in turbine systems including lubricating oil systems, steam and water seal systems and hydraulic power units and discuss irregular operations within a system identify the locations of the turbine supervisory instrument and describe their functions describe the steam turbine control concepts. Speed control system turbine gland seal the turbine glands. Gland steam must have appropriate temperature and pressure which must be controlled during startup. Under certain conditions the gland is sealed by an auxiliary steam supply, and under other conditions the gland is self sealed by turbine inlet steam.
Steam turbine a steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into useful mechanical work. Main root causes for performance deterioration are. Turbine sealing system gland sealing labyrinth seal turbine self sealing duration. The function of the gland steam condenser is to maintain a subatmospheric pressure at the outermost leakoff belt of the glands and thereby prevent the leakage of steam from the glands into the turbine hall, where it would condense on the walls and plant. This system also prevents air leakage into the low pressure turbine glands. Labyrinth packing an overview sciencedirect topics. These requirements include basic design, materials, fabrication, inspection testing, and preparation for shipment.
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