All about the turbine, WHAT IS A TURBINE:-A turbine is a turbo machine with at least one moving part called a rotor assembly, which is a shaft or drum with blades attached. Moving fluid acts on the blades so that they move and impart rotational energy to the rotor. WHY TURBINE IS USED? , turbine introduction, turbine components involved in turbine , working of turbine, DIFFERENT PARTS OF TURBINE, CASING:-mild steel , steel and molybdenum steels , chromium steels. , NOZZLE, ROTORS:-HP ROTOR B) LP ROTOR C) IP ROTOR. , BLADES, FIXED BLADES, BEARINGS, CONTROL VALVE, CONCLUSION, turbine use , images of different components of turbine

1. INTRODUCTION
• WHAT IS A TURBINE?:-
A turbine is a turbo machine with at least one moving part called a rotor
assembly, which is a shaft or drum with blades attached. Moving fluid acts on the
blades so that they move and impart rotational energy to the rotor.
• HOW TURBINE WORKS?
Simply stated, a wind turbine works the opposite of a fan. Instead of using
electricity to make wind, like a fan, wind turbines use wind to make electricity.
The wind turns the blades, which spin a shaft, which connects to a generator and
makes electricity.
• WHY TURBINE IS USED?
Wind turbines convert the kinetic energy in the wind into mechanical power. This
mechanical power can be used for specific tasks (such as grinding grain or
pumping water) or a generator can convert this mechanical power into electricity.

2. • DIFFERENT PARTS OF TURBINE:-
1. CASING
2. NOZZLE
3. ROTOR
A)HP ROTOR
B) LP ROTOR
C) IP ROTOR.
4. BLADES
5. FIXED BLADES
6. BEARINGS
7. CONTROL VALVE.

3. 1)CASING:-
The HP casing are large structures that contain steam at the temperature and
pressure corresponding to the exit of the hot gas path - and if there is an inner
cylinder it must handle steam at the maximum temperature and pressure. Always
both the outer casing (shell) and the inner cylinder are made of the same material
to avoid a thermal mismatch. As the material depends on the design of the turbine.
Needless to mention, the best material is most expensive so the material is always
selected according to the need.
In present the material used to manufacture HP Casing is depend upon the
temperature limit. The temperature limit of 2Cr-Mo steels is 566°C whereas
9CrMoVNb all go up to 600°C and 12Cr steels is limited to 620°C. For higher
temperatures, nickel based alloys are required.
In olden days the HP casing is made of mild steel , steel and molybdenum
steels , chromium steels.

4. 2) NOZZLE:-
• It is chiefly used for producing a large velocity steam jet. In other words, its chief
use is to produce a jet of steam for the purpose of driving steam turbines. The
function of a nozzle in an impulse turbine is to admit steam to the active or
moving parts of the turbine .
• A nozzle is a device designed to control the direction or characteristics of a fluid
flow (especially to increase velocity) as it exits (or enters) an enclosed chamber or
pipe. A nozzle is often a pipe or tube of varying cross sectional area, and it can be
used to direct or modify the flow of a fluid (liquid or gas) .
• The commonly used nozzle is manufactured by brass, stainless steel, cast iron,
bronze, tungsten carbide, nickel, silicon carbide, super alloys, titanium,
nickel alloys, tantalum. The nozzles are also made from Teflon materials like
the PTFE, from Kynar (PVDF).
• In olden days the Nozzle is generally made up of Nickel ,Stainless Steel, Cast
Iron and Titanium.

5. 3)ROTORS:-
• A) HP ROTOR:-
• B)LP ROTOR:-
• C) IP ROTOR:-
• HP ROTOR:-
High temperature rotors are required to have a combination of creep strength,
rupture strength and ductility. Creep is a high temperature phenomenon and
traditional design methods involve the selection of materials which provide the
required creep strength and creep rupture ductility during the required design life.
This is conferred by rotors manufactured from forged Chromium Molybdenum
Vanadium steel (Cr Mo V), a ferritic material which provides the best possible
creep properties. While the best possible creep properties are required on HP
rotor forgings, the HP problem is simplified by modest dimensions of HP rotors.
In olden days the Hp rotors are just made up of the stainless steel , Vanadium steel
, Mild steel.
• LP ROTOR:-

6. ◦ For low temperature rotors, the main requirements are relatively high tensile
strength combined with high toughness.
◦ The 3.5Ni Cr Mo V monobloc rotor forging is currently used . The
manufacturing facilities a the complication of shrink fits in the case of built-up
rotornd forging technology required for the manufacture of monobloc rotor
forgings of very large size and weight are fully able to meet the designers
requirements. No limitations are identified for the forgings of 2-pole 900 MW
units currently under consideration. Ni Cr Mo V steel containing up to 3.5% Ni
has been used for both shafts and discs for built-up LP rotors and is the first
choice to achieve the tensile properties necessary for large rotors. . Alloy
steels are used for tensile strength and weldability.
◦ Since LP rotors may run at temperatures not much in excess of ambient, the
provision of safeguards against the danger of brittle fracture is important. The
use of materials for discs, shafts and monobloc rotors of the lowest possible
fracture appearance transition temperature (FATT) and subject to stringent
non-destructive testing and fracture mechanics assessment provides the
necessary framework for the safe operation of LP turbines. 3.5% Ni Cr Mo V
steel has a low value of FATT. In the water-quenched and tempered condition,
and with careful control of composition, high tensile properties can be matched
with a FATT well below ambient temperature and a consequential high fracture
toughness.
• IP ROTOR:-
The IP rotor poses a much more serious problem, especially in turbines employing
a reheat cycle. Full steam temperature is encountered on discs at the IP inlet
stages, which have larger diameters and blades than equivalent stages on the HP
rotor exposed to steam at the same temperature. Both at the rim and the bore, the

7. stresses are such that steam cooling may be necessary, even with steels having the
best creep properties.
The requirement for good creep strength and the necessary proof strength in
conjunction with a rotor forging of heavy section is achieved on current rotors by
the use of ICr IMo 0.25V steel alloy.
In olden days the IP Rotor is just made up of the mild steel .
4) BLADES:-
Turbine blading alloys are chosen for their ability to provide properties particular
to the mechanical and environmental service which they must endure.
One of the first considerations of LP blading, for example, is the ability to resist
corrosion and scaling in fast-flowing wet steam. This generally rules out low alloy
steel and blades are made from either stainless steel or titanium alloys. A second
requirement is adequate tensile strength to resist steady centrifugal and bending
stresses. Strength without ductility is not desirable; ductility is needed to
accommodate stress peaks and concentrations. Ductility also is needed to resist
rubbing, and, in the case of shrouded blades, to permit the peening of tenons to
secure the shroud. Impact strength is also necessary, since contact with foreign
objects is sudden. Water slugs can produce impact loading.
Modern turbine blades often use nickel-based super alloys that incorporate
chromium, cobalt, and rhenium. Aside from alloy improvements, a major
breakthrough was the development of directional solidification (DS) and single
crystal (SC) production methods Ceramics and ceramic-metal mixes. Nickel-
based super alloy, outside air is circulated through channels inside of the turbine
blades. For lower pressure turbine blades iron-based super alloy or even stainless
steel. The metals used for turbine blades are often grown as a single crystal.

8. 5) FIXED BLADE:-
Fixed blades redirect the steam after it flows from a moving blade (which is
attached to a moving spinning rotor). The steam flows through one row of moving
blades then is redirected using a fixed blade to the next row of moving blades.
This occurs to the steam as it goes from row to row of blades ultimately using up
most of the steams energy. Eventually the steam that is left over is either
condensed or is used for an auxiliary purpose .
Fixed blades are as shown above in the picture .There are two methods of
constructing the stationary nozzle blading. Built-up blades, machined from the
solid, are used for nozzle plates and steel diaphragms, whilst cast-in blades,
formed from steel plates embedded into cast iron diaphragms, are used where
temperatures are below 230°C.
Fixed blades are made of nickel-based super alloys that incorporate chromium,
cobalt, and rhenium. Aside from alloy improvements, a major breakthrough was
the development of directional solidification (DS) and single crystal (SC)
production methods Ceramics and ceramic-metal mixes. Nickel-based super
alloy,
6)BEARINGS:-

9. A turbine rotating at high rpm will generate axial thrust. A bearing prevents this
axial thrust from developing into axial motion. Steam turbine is one of the most
popular mode of energy manufacturing. Bearings are one of the most important
components that assist the smooth functioning of the turbines.
Two bearings normally support each section of the turbine shaft, although, with
solid couplings, some designs only use one bearing between cylinders in order to
save length and bearing losses. Plain white metal journal bearings are invariably
used because of their high loading capacity, reliability and absence of wear due to
hydro dynamically generated films of lubricating oil.
The white metal surface is either cast into a mild steel liner to form a bearing
shell, which is supported in the bearing body, or cast directly into the bearing
body itself.
7)CONTROL VALVE:-
Steam inlet valves perform one of two functions, protection or control.
Steam inlet control valves regulate the flow and/or the pressure of steam through
the turbine. Their position, from closed to fully open, is determined by the turbine
electronic controlled.
Materials used in the manufacture of steam turbine valve components have to
withstand many stress cycles of steam flow, pressure and temperature changes.
Operating pressures and temperatures have increased for new power plants in both
sub critical and ultra critical units .

10. • CONCLUSION:-
1. After performing this micro project we get the detailed knoweldge about
materials which is used in the past and in the present modern turbines .
2. We also get that why this materials used.
3. The materials choose to manufactured the turbine and turbine parts are
generally according to the conditions and the properties of the material.