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Steam turbines account for more than half of the world’s electricity production in power plants around the world and will continue to be the dominant force in electricity power generation for the foreseeable future. The enhancement of steam turbine efficiency is increasingly important as the urgency to reduce CO2 emissions into the atmosphere is a problem at the forefront of power production. Increasing efficiency in steam turbines, and other components of power plants, will help meet the growing demands for electricity worldwide while reducing harmful greenhouse emissions.

Steam turbines are used in coal-fired, nuclear, geothermal, natural gas-fired, and solar thermal power plants. Also, steam turbines are increasingly needed to stabilize fluctuating power demands from solar and wind power stations as renewable energy sources grow worldwide. The current emphasis on steam turbine development is for increasing efficiency, mainly by increasing steam turbine capacity, as well as increasing operational availability, which translates to rapid start-up and shut down procedures.

The efficiency of steam turbines increases with increasing inlet temperature and inlet pressure; however, limits are imposed in the case of Small to Medium sizes steam turbines due to the limited steam flows and thus the related boiler design parameters. There are many methods to improve the thermal efficiency of a steam cycle, in the case of small to medium size steam turbines, but a balance must be reached between efficiency improvement and economical costs with each design. It is also important to consider the complexity owing to increasing steam pressure and temperature beyond a reasonable level.

Usually, it pays in terms of overall all cost-benefit if the inlet pressures and temperature are in the range of about 67 bar and 495 deg C for Steam Turbines of capacity range up to 5 MW. This is considered to be a sweat spot towards reasonable investment cost on one hand and the efficiency on other.

Certain Steam Turbine technologies are intrinsically superior in terms of efficiency compared to others. Reaction Steam Turbine technology offers better efficiency than impulse steam turbine technology. However, there are other limitations when such technology is applied to Industrial Steam turbines with varying steam flows. Hence a balance between the selection of turbine technology is very important to ensure a practical steam turbine installation in the small to medium range.

Turtle Turbines manufactures steam turbines considering all these aspects while configuring the basic steam turbine design. This has resulted in a balanced Steam Turbine design that provides the best in its class efficiency without compromising the operational challenges in Industrial Steam Turbines.

Turtle Turbines is one of the most reputed Steam Turbine Manufacturers In India.

An effective way to increase energy efficiency is to recover waste heat. The process industry mainly consumes two types of energy. Fossil fuel to generate process heat and electric energy to drive motors and for use in specific process steps. Waste heat can also be used to generate steam, which can be used to drive mechanical processes or generate electricity. Hence cogeneration facilities are designed to use one energy resource to create both heat and electricity. Steam Turbines play a very important role in waste heat recovery applications. Steam Turbines are very essential to generate the power in waste heat recovery process because it generates power within 25% of the cost of the grid / utility power cost.
In the waste heat recovery process, the energy and cost-saving potential are closely linked to the flow of heat in the plant in most cases. Waste heat recovery is basically used to try to recover maximum amounts of heat in the plant and reuse it as much as possible, instead of just releasing it into the atmosphere. Waste heat recovery steam generators can be used to generate steam for district heating or factory processes or to drive a steam turbine to generate more electricity.
Turtle Turbines supplies steam turbines for Waste Heat Recovery also. For more information please visit turtleturbines.com

Turtle Turbines is one of the most reputed Steam Turbine Manufacturers In India.

The modern Steam Turbine was invented in 1884 by Charles Parsons and in 1980 Carl G. P. de Laval designed a high-speed small reaction turbine that worked at about 40,000 rpm. De Laval then developed Single Stage impulse turbine that used converging-diverging nozzles. C.E.A. Rateau developed the first multistage steam turbine. At about the same time Charles Curtis developed the Velocity-compounded impulse turbine.

As the century passed, many people recognized the potential of a steam turbine. Nowadays many reputed brands are available in the market to manufacture steam turbines for commercial use. Various industry-specific standards for example API 611 and API 612 standards are used in the Oil and Gas Industry. The advancement in the technology of Thermodynamics, Aerodynamics, Fluid Dynamics, Metallurgy, and New manufacturing techniques has made modern turbines more reliable.

Turtle Turbines is one of the premier Steam Turbine Manufacturers in India. At Turtle Turbines, we manufacture efficient, Reliable, Robust, and Intelligent Turbines bringing the Technology to a new level.

Turtle Turbines is one of the most reputed Steam Turbine Manufacturers In India.

Cogeneration means combined heat and power (CHP). Cogeneration is defined as the sequential generation of two different forms of useful energy from a single primary energy source. It produces electricity and thermal energy at high efficiencies using a range of technologies and fuels. Cogeneration used for many years all over the globe across different industries in several forms like steam boilers and steam turbines, gas turbines, reciprocating engines, and heat recovery systems. In Cogeneration, the fuel is used first to drive the prime mover to generate electricity and produce heat. The heat is then used to boil water and generate steam. Some of the steam is used to support a process while the remaining steam is used to drive a steam turbine to generate additional power.
Cogeneration is very efficiently helpful by using waste heat recovery technology to capture wasted heat associated with electricity production. Cogeneration systems typically achieve total system efficiencies of 60 to 80%. For micro-cogeneration systems, the main output is heat, with some electricity generation, at a typical ratio of about 6.1 for domestic appliances.
In the case of steam turbines, cogeneration technologies widely commercialized include extraction and backpressure steam turbines. The capital cost to build a cogeneration plant and the size of the plant required to demand a constant load 24/7 for viability and financial advantages, but the main advantage of this type of cogeneration is the long plant life for the steam turbines due to low wear and tear. In steam cogeneration systems the fossil fuels mostly used are coal, oil, and natural gas.
Cogeneration is likely to be most attractive because the requirement of demand for both steam and power is balanced which is consistent with the range of steam. And also power output ratios that can be obtained from only suitable cogeneration. Cogeneration is also most likely to be attractive for a single plant or group of plants that has sufficient demand for steam and power to permit economies of scale to be achieved. Cogeneration also helps peaks and troughs in demand can be managed or, in the case of electricity, adequate backup supplies can be obtained from the utility company.
The ratio of heat to the power required by a site may vary during different times of the day and seasons of the year. Importing power from the grid can make up a shortfall in electrical output from the cogeneration unit and firing standby boilers can also satisfy additional heat demand.
Turtle Turbines is one of the most reputed Steam Turbine Manufacturers In India. Turtle Turbines has been in the business of supplying Steam Turbines for Cogeneration and Micro Cogeneration. Turtle Turbines has supplied numerous Steam Turbine Cogeneration plants across India, South East Asia, and African Countries.

A governor is the component of the steam turbine control system that regulates the rotational speed in response to changing load conditions. The governor output signal manipulates the position of the steam inlet valve or nozzles which in turn regulates the steam flow to the turbine. The governing of the turbine is necessary as a turbine is directly coupled to an electric generator which is required to run at a constant speed under all fluctuating load conditions
In a steam turbine, there are three types of governors are used.
Throttle Governing of Steam Turbine
Nozzle Control Governing Of Steam Turbine
Bypass Governing of Steam Turbine.
Throttle Governing of steam turbine
In this governing system, the pressure of the steam turbine is reduced at the Turbine entry thereby decreasing the availability of energy. In this method, steam is pass through the restricted passage thereby reducing its pressure across the governing valve. The flow rate is control through a partially opened steam turbine control valve. Throttle governing is used for small turbines. Its cost is less and it has a simple mechanism. In throttle governing the steam is throttled whenever the load falls below the design load to maintain turbine speed constant. In this system, a centrifugal governor is driven from the main shaft of the turbine by belt or gear arrangement. A control valve is used to control the direction of oil flow.
Nozzle control governing steam turbine
Nozzle control governing of steam turbine is basically used for part-load condition. Some sets of nozzles are grouped together and each group of the nozzle is supplied steam controlled by valves.
Bypass governing of steam turbine
The bypass line is provided for passing the steam from the first stage nozzle box into a later stage where work output increases. This bypass steam is automatically regulated by the lift of the valve which is under the control of the speed of the governor for all loads within its range.

The rotor is statically and dynamically balanced when it is assembled with blades. Each bladed disc is individually balanced prior to assembly for built-up rotors.
Static balance means that the weight is evenly disposed around the axis of the shaft. It can be checked by rolling the rotor on horizontal knife-edge supports.
Dynamic balance means that the moments of the out-of-balance weights along the axis about either bearing add up to zero. This is checked by spinning the rotor on resilient bearings, detecting the vibration, and adding or subtracting weights until the vibration is negligible.

A modern balance machine allows for high-precision balancing and, to a significant part, removes the trial-and-error methods of the past.
Rotors are normally balanced at low speed and weight adjustments are made in two convenient planes, one at each end of the rotor. This adjustment may be by varying screwed plugs in tapped holes, or by adding balance weights at specific circumferential positions. Tee slots are machined circumferentially in the periphery of the rotor front and rear half-coupling flanges to permit the weights to be positioned and retained.

The aim of balancing is to reduce the amplitude of vibration to a tolerable level, which can be taken to be about 25 /mi at the bearing pedestals.
As rotors become larger and more flexible, it is increasingly important to understand their modal behavior so that balancing can ensure smooth running over the speed range.

Larger LP and generator rotors with essential speeds below running speed are overseeded and, if necessary, balanced in a vacuum chamber in the fully-bladed condition, where they may be run without being overheated owing to windage.

Rotors are run in bearing bushes and pedestals as closely as possible to simulate site conditions in the vacuum chamber and the high-speed pit. Measurement of journal or pedestal vibration is possible, and balancing can be done at precisely controlled speeds anywhere in the range required. The vibration margin provided by the balancing standards obtained during factory testing must be sufficient to accommodate site conditions.

Turtle Turbines balances its Rotors using the best the class technology from Schenk Germany to stringent ISO Grades.

Heat rate is defined as the total amount of energy required to produce one-kilowatt hour (kWh) of electricity by electric generators or power plants that convert fuel into heat and into electricity. The heat rate is equal to the (input energy) / (output energy). Steam Turbine heat rate is the ratio of total heat rate energy utilized in the steam turbine divided by electricity generation through the steam turbine. Heat rate is one measure of the efficiency of electrical. Turbine heat rate tells the cyclic efficiency of the steam turbine as well as the thermal efficiency of the power plant.

If the heat rate is less then the cyclic efficiency of the Rankine cycle is more and thermal efficiency is also higher in the thermal power plant. Different data is measured in thermal power plants like flow, pressure, and temperature of main steam, cold reheat steam, hot reheat steam, and feed water to calculate turbine heat rate. Cold reheat steam flow needs to be calculated from the heat balance diagram.
It is the input rate required for generating unit power. The heat rate can also be described as the ratio of thermal inputs to electrical Output. The lower the heat rate higher the efficiency of a steam turbine. In a thermal generating system, incoming and outgoing energy typically exist in the same value or unit. The formula of heat rate is Rh = Ws x c x ∆T.
Heat rate is also important for boiler performance because net heat rate permits a better comparison of units using steam-driven components to those using electrical motors, as the steam used to drive large components is typically less expensive than electricity. But it robs the steam turbine of some capacity.
A heat rate is the inverse of efficiency. A lower heat rate is better. Heat rate is used to define the efficiency of a steam turbine.

The steam turbines are used in oil and gas, distillery, chemical plants, food processing industry, or in industries where the steam is a by-product. While operating the steam turbine at maximum load, different losses of steam occur in a steam turbine. The turbine uses every single bit of heat drop produced by steam. But practically turbine work done is much less than the isentropic heat drop of steam used. Because at the time of operation some internal losses occurred. Practically 100% gross efficiency is not possible for any turbine. When the turbine works some factors have reduced the output of the turbine, known as the losses in a steam turbine.
Following are the major losses that occur in a steam turbine.
Admission losses, Leakage losses, Nozzle Friction losses, Blade losses, Wheel Friction losses, losses due to Mechanical friction, Residual Velocity loss, losses in regulating valves, loss due to wetness of steam, Governing losses, Exhaust losses, Radiation and convection losses, Losses due to moisture, Carryover losses.
Leakage loss – Leakage loss occurs between the shaft, bearings, nozzles, and stationary diaphragms.
Windage losses – windage loss occurs when moving rotor blades come in contact with inactive steam then there is a move of energy as of blade to steam.
Nozzle Losses – When fluid is transferring from convergent to divergent or reverse then its momentum might be lost. Pressure losses occur when fluid flows from convergent to divergent. Head losses that occur in nozzles are due to pipelines.
Friction losses occur due to the flow of steam through nozzles on moving and stationary blades.
Blade friction loss – It is due to steam gliding over the blades and friction on the surface of the blades.
Wheel friction loss – When steam passes through the rotating turbine wheel, it produces some resistance on the turbine wheel.
Losses due to mechanical fraction – This loss is for turbine bearing. It is due to the shaft and wheel bearing and also the regulating valve of the turbine. This loss may be reduced by proper lubrication of the moving parts of the turbine.
Loss in regulating valves – Before entering the steam to the turbine, it passes through the boiler’s stop and regulating valve. Steam gets throttled in these regulating valves and as a result, steam pressure will be less than the boiler pressure at the entry of the turbine.
Loss due to wetness of steam – It is due to the moisture present in the turbine. When steam passes through the lower stage of the turbine, it becomes wet. At the lower stage, the velocity of water and steam are different and will not form a homogeneous mixture. That’s why the velocity of water particle is less than that of steam and water particle has to be dragged with the steam and some part of the kinetic energy of steam is lost.
Governing loss – This loss is due to the throttling of the steam at the main stop valve of the governor.
Turtle Turbines designs and manufactures Steam Turbines with required attention towards reducing the internal losses, thus our Steam Turbines deliver the highest efficiency in their class. . Turtle Turbines provide solutions for all types of failures in a steam turbine. For more information please visit https://turtleturbines.com