How do you warm up a steam turbine?

1. Crack open the steam supply isolating valve and warm up the steam pipe to the turbine stop valve.
2. Crack open the main stop valve sufficient only to admit steam to the turbine casing, via the nozzles for warming through purpose.

What material is used in turbine casing?

A material used for the casing is 1Cr-1Mo-1/4V low carbon alloy cast steel or 11Cr-1Mo-V-Nb-N cast steel. From the standpoint of exhaustion of fossil fuel such as petroleum, coal and so on and energy saving, it is required to improve the efficiency of a thermal power plant.

What is Casing in steam turbine?

Steam turbines consist essentially of a casing to which stationary blades are fixed on the inside and a rotor carrying moving blades on the periphery. The rotor is fitted inside the casing with the rows of moving blades penetrating between the rows of fixed blades.

What is warming through a steam turbine?

Open the manoeuvring valve bypass or ‘warming through’ valve, if fitted. This allows a small quantity of steam to pass through the turbine and heat it. Raising a small vacuum in the condenser will assist this warming through. The vacuum can now be raised to its operational value and also the gland steam pressure.

How long does it take to warm up a steam turbine?

They should be warmed up and cooled down slowly to minimize the differential expansion between the rotating blades and the stationary components. Large steam turbines may require approximately five to nine hours to warm up.

Which type of material is used for casing?

Casing is typically made from carbon steel, but as the primary structural component of the well the grade of steel used to make the casing, and the specifications of the finished material, are very important.

How are turbine casings made?

A method for producing a turbine casing for a rotating machine is provided. The casing is manufactured by a casting process, and is cast in two casing halves which are separated by a parting plane which passes axially through the turbine casing.

Why casing is used in turbine?

The present invention provides a turbine casing which allows that part of the casing which forms the outer wall of the main flow duct to remain reasonably concentric and hence enables control of the leakage past the turbine rotor tips.

Why steam is used in turbine?

While using steam turbines the efficiency increases rapidly than the other turbines. Because of the high pressure and high kinetic energy, steam turbines are mostly used. As steam contains thermal energy, high pressure is obtained for running the turbines, to generate electricity.

What are the two main types of steam turbines?

Two types of steam turbines must be considered, condensing and noncondensing.

How is thermo mechanical analysis of steam turbine casing?

So that problems such as stress corrosion, cracking and fatigue of steam turbine casing, In this work the thermo mechanical analysis of steam turbine casing will be established by finite element method. In this work the temperature and stress distributions for turbine inner casing were calculated by finite element analysis.

How are the blades of a steam turbine arranged?

Each row of fixed nozzles and moving blades is called a stage. The blades rotate on the turbine rotor and the fixed blades are concentrically arranged within the circular turbine casing. In all turbines the rotating blade velocity is proportional to the steam velocity passing over the blade.

How is the steam ring attached to the casing?

The casing is that portion of the turbine that either supports or supported by the bearing housings. The steam ring is attached to or is a part of the casing. All casing joints have metal to metal sealing surfaces no strings or gaskets are used.

What do you need to know about single stage turbine casing?

1.1 Single Stage Turbine Casing Single stage turbine casings are two piece casings. The casing consists of the upper half and the lower half the lower half casing houses both the inlet and exhaust connections. The bearing housings are either cast integrally with or bolted to the lower half casing.