Power Plant Construction and QA/QC

Section 3.1 & 2 – Steam Turbine Fundamentals and Design

Engineering Technology Engineering Technology DivisionDivision

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Section 3.1 – Steam Turbine Fundamentals

Overview

• Hero Reaction Turbine – 120 B.C.

• First Practical Turbine – 1884, C. Parsons

• First Power Plant – 7.5 kw – 1890

• Reaction, Impulse and Velocity-Compounded

• Reheat Steam – 1930’s

• Last 100 years Turbine is the key element in generating electricity

• Turbines run Generators, Pumps, Fans, etc.

• Today up to 1,500 MW

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Section 3.1 – Steam Turbine Fundamentals

Overview

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Section 3.1 – Steam Turbine Fundamentals

Fundamentals

Coal, Natural Gas, Nuclear, Biofuel,

Waste Fuel

Energy TransferEnergy Transfer

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Section 3.1 – Steam Turbine Fundamentals

Reaction Turbines

Newton’s third law of motion – For every action Newton’s third law of motion – For every action there is an equal and opposite reaction.there is an equal and opposite reaction.

Narrowing Steam Path Narrowing

Steam Path

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Section 3.1 – Steam Turbine Fundamentals

Impulse Turbines

Steam / Gas Flow

Fixed Vanes

Moving Blades

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Section 3.1 – Steam Turbine Fundamentals

Reaction – Impulse Comparison

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Section 3.1 – Steam Turbine Fundamentals

Velocity-Compounded Turbine

Velocity compounding is a form of staging which by dividing the work load over several stages results in improved efficiency and a smaller diameter for the blade wheels due to a reduction in Ideal blade speed per stage.

Inlet PressureInlet Pressure

Inlet Inlet VelocityVelocity

P =1

V

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Section 3.1 – Steam Turbine Fundamentals

Turbine Components - Blades

Reaction

Impulse

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Section 3.1 – Steam Turbine Fundamentals

Turbine Diaphragms

Diaphragms contain the fixed bladesDiaphragms contain the fixed blades

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Section 3.1 – Steam Turbine Fundamentals

Steam Turbine Casing

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Section 3.1 – Steam Turbine Fundamentals

Turbine Rotor

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Section 3.1 – Steam Turbine Fundamentals

Turbine Shaft and Casing Seals

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Section 3.1 – Steam Turbine Fundamentals

Turbine Types

Straight HPStraight HP

Tandem HPTandem HP

Tandem LPTandem LP

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Section 3.1 – Steam Turbine Fundamentals

Turbine – Multiple Sets

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Questions?

Section 3.1 – Steam Turbine Fundamentals

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Section 3.2 – Steam Turbine Design

Overview

Classification by;

• Type – Reaction or Impulse

• Steam Temperature and Pressure

• Configuration – Compound, Tandem Compound, Cross Compound

• Reheat

• Output – MW

• Structural Elements

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Section 3.2 – Steam Turbine Design

Turbine Design - Basics

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Section 3.2 – Steam Turbine Design

Materials

• Blades

• Stainless Steel – 403 & 422 (+Cr)

• 17-4 PH steel (+ Ti)

• Super Alloys

• Rotor

• High “Chrome – Moley” Steel – Cr-Mo-V

• Low “Ni Chrome Steel – Ni-Cr-Mo-V

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Questions?

Section 3.2 – Steam Turbine Design