What is heat soaking in turbine?

The heat soak-back occurring in engines under post-shutdown conditions is a well-known phenomenon. This behavior is caused by the transmission of accumulated heat from hot parts or cavities during idle operation (such as turbines, contention rings, etc.) to colder ones (combustion chamber, injectors, etc.)

What is soaking time in turbine?

This is called as “soaking time” of a machine. Such soaking time will result in uniformity of temperature (equilibrium condition is acheived) of the “turbine internals”. Heat absorption is done at some “specified speed” of the machine say at 1000 -1200 rpm for 45 minutes in case of 110MW BHEL set.

What is overhauling of turbine?

The overhaul involves the complete disassembly, inspection, repair and reassembly of the turbine and the generator. Our professionals check all the quality parameters associated to this service and perform the service in the best possible.

What is hogging in steam turbine?

1) Hogging is when the turbine is shut down faster than normal or under trip conditions and the natural cooling of the rotor is not allowed to happen, usually happens when the barring system fails to start, the rotor bends in an upward motion in the middle and makes contact with the stator or casing thus allowing …

What is thermal soak back?

[‚thər·məl ′sōk‚bak] (engineering) A phenomenon whereby, due to the lag in propagation of temperature changes through insulating materials, the maximum temperature of a thermally protected structure may be reached a certain time after the protective coating has reached its maximum temperature.

What is critical speed of turbine?

Critical speed of the turbine is the rotor speed at which natural frequency of the assembled rotor (rotor shaft with discs, blades, shrouding strips etc in assembled condition) becomes equal to the operating speed. This is usually a expressed as a range (critical speed range). There are multiple critical speeds.

How hot is the steam in a steam turbine?

A steam turbine consists of stationary and rotating blades on an axle. High pressure steam enters the turbine. The steam can be anywhere from 200 °C to 400 °C. The stationary blades direct streams of high pressure steam onto the rotating blades, which turns the axle.

What is turbine maintenance?

Turbine repair and maintenance services provide maintenance, overhauls, and repairs to wind, gas, steam, and water turbines. Turbine repair and maintenance services may include troubleshooting, testing, inspection, disassembly and reassembly, maintenance, field or shop repair, and complete machine overhauls.

What is steam turbine and how it works?

In simple terms, a steam turbine works by using a heat source (gas, coal, nuclear, solar) to heat water to extremely high temperatures until it is converted into steam. The turbines are connected to a generator with an axle, which in turn produces energy via a magnetic field that produces an electric current.

Why ejector is used in turbine?

The main function of the ejector is to maintain the vacuum value in the condensation system of the turbine. According to this, main indicators of the efficiency, which influence the vacuum value in the condenser (pressure of the I stage and the length of the performance curve) are also connected with the reliability.

What is whirling speed of shaft?

Whirling speed or Critical speed of a shaft is defined as the speed at which a rotating shaft will tend to vibrate violently in the transverse direction if the shaft rotates in the horizontal direction. In other words, the whirling or critical speed is the speed at which resonance occurs.

What is meant by soaking time of a turbine?

This is called as “soaking time” of a machine. Such soaking time will result in uniformity of temperature (equilibrium condition is acheived) of the “turbine internals”. Heat absorption is done at some “specified speed” of the machine say at 1000 -1200 rpm for 45 minutes in case of 110MW BHEL set.

What is a steam turbine?

A turbine is a device that extracts the energy from a fluid flow and converts it to useful work. For a steam turbine, steam is the driving source of the energy. I will explain the concept of compounding via an analogy.

How is heat absorption done in a steam turbine?

Heat absorption is done at some “specified speed” of the machine say at 1000 -1200 rpm for 45 minutes in case of 110MW BHEL set. In such cases requisite amount of steam is admitted so as to maintain” constant speed “ say as 1000 rpm, for 45 minutes, till the other parameters will get stabilised (say differential expansion).

What is the GSS of a steam turbine?

Gland Sealing System (GSS) of a steam turbine – The steam turbine inlet pressure will be in Hundreds of Bar but when the steam exit , the pressure drops to either well below atmospheric pressure (Condensing Turbine) or at relatively lower pressure (Extraction turbine).