Table of Contents
Definition and introduction of boiler:
Electric and steam boilers, such as those of ancient trains and ships, were used to power transportation.
The first models were called “Scotch Marine,” and some of the first fire tube boilers were made of stainless steel tubes that were welded together.
The same boiler is closed from which the steam is made in the same way as in
Fire tube: water is surrounded by a tube, and hot gas flows in the tube and
Water pipe: Hot gases are trapped in the pipe, and water flows through the pipe.
Definition of boiler:
In the closed container, the fluid (mostly water) is heated until it is boiled to reach high-pressure vapor.
Boilers are used in power plants to produce steam.
They are used in power plants where turbines are used to generate electricity.
The fuel used in this can be classified into three categories.
Wood, coal, briquettes (a molded block of coal dust), petroleum coke, and rice husks.
LDO (light diesel oil), furnace oil.
LPG (Liquefied Petroleum Gas), LNG (Liquefied Natural Gas), and PNG (Piped Natural Gas) can be used for this purpose.
Principle and Operation of Boiler:
In the evaporator, the thermal energy of the tube gases moves through the liquid through convection. The fuel consumed in the heater is used as air gas.
These pipe gases bypass the enclosure in a curved or cylindrical form of combustion. The heat of the atmospheric gases is escaping from the hot water.
Operation principles of boiler:
The boiler is simply an exchange where the water is heated as hot water, and the flue gases are heated as hot water. The flow of heat is transferred from the water to the cold by convection, which is the force of the water.
• The can is half full. Fuel is consumed, and air gases flow over the support. These gases heat the water and make it hot.
• This steam is drawn from the cylinder above the support. The water supply is provided by a valve that keeps the boiler pressure constant.
• As air pressure rises or water density rises, boiler pressure drops. That is, if the intake rate is high, as opposed to the exhaust air, the weight of the heater increases. And the pressure is controlled with the help of oil and water.
Classification of boilers:
Boilers are mainly classified as shell and water tube boilers.
Shell and tube boilers:
Shell and tube boilers are personal. Tubular boilers for motorcycles; Machine These long hot metal tubes are placed in water. Fire tube boiler tubes usually have a small fire tube and are easy to find. Its capacity is 25 tons/h and 17.5 kg/cm2.
Types of Fire tube boiler:
These are the first high-quality fire tube boilers. It is a long horizontal cylinder with a single chimney. The oil thickens to a grey grade which burns to release hot gases. Hot gases lead to water. The process happened in the side chimney and finally in the bottom chimney.
The boiler was often enclosed in a brick chamber from the beginning for maximum efficiency.
The area in Lancashire is similar to the one in Cornish, but it has two large craters. The pressure of the boiler is from 0.7 MPa to 2 MPa, and its efficiency is 65-70%. The fuel in this generator is added to the grate, which burns the gases.
The hot gases enter the front of the boiler and leave the boiler at the back, then enter the bottom of the chimney and move towards the front. At the front, the hot gases exit the bottom of the chimney, enter the side chimney, return to the back of the boiler, and enter the main outlet. 85% of the heat is transferred when the hot gases are in the chimney, while 15% is transferred when it is at the bottom and side of the chimney.
A locomotive boiler has three main components:
- Double wall oven;
- Horizontal, cylindrical “barrel boiler” with a large number of small heating tubes; and
- Smokebox with a chimney for gas exhaustion.
Fuel is burned to produce hot gases. Fuel is fed through the fuel port. The hot gases are diverted into the fire pipe with the help of a resistor. The smoke is collected in a smoke drum placed on top of the furnace. The moist air passes through the superheater inlet manifolds and, after passing through the tubes, returns to the superheater outlet manifold and is sent to the air engine.
Locomotive-type boilers are also used in traction engines, steam rollers, portable engines, etc.
Depending on the construction, they can be classified as wet return boilers and dry return boilers.
This is the back part of the combustion chamber where the hot gases travel from the bottom of the first (furnace) to the second tube.
Wet back boilers:
As the name implies, the return chamber is surrounded by water in water return boilers. The boiler returns to the room surrounded by water, so the heat from the flue gases is used more. Radiation loss is reduced because no part of the heating chamber is open to the air. Instead, it is surrounded by water. This means less waste and less fuel consumption. The most efficient modern boilers on offer are the wetback type.
Dry Back Boilers:
The return chamber in dry boilers is not completely surrounded by water. The spine is released into the air. This leads to radiation loss as the radiant heat is lost to the air and not to the water as with return water boilers. Older-generation boilers were often dry.
However, wet boilers guarantee less radiation loss and therefore save fuel.
The installation of the tubes includes the number of passes that the tube will have to pass the heat from the furnace to the boiler before it is released. These can be two-pass and three-pass boilers.
Depending on the arrangement of the tubes, boilers can be two-pass or three-pass boilers.
In two stages, the flue gases pass twice through the boiler.
The flue gases must be cooled before entering the return chamber. Excessive heat causes burning and bursting in the tube. The heat rate is high in the first pass, this rate decreases with an increasing pass.
Three pass boilers:
A three-pass design provides three opportunities for heat transfer. The temperature of the 3-pass chimney will be lower
than the 2-pass boiler with the same design and efficiency. Efficiency is higher than two-pass boilers.
Each pass through the boiler must be designed with a cross-sectional area to achieve the optimal flue gas velocity, which increases heat transfer and reduces efficiency by stealing internal heat.
Water tube boilers:
In water boilers, water and steam circulate inside the tubes and hot gases circulate outside. Today’s most advanced boilers are of the water type. The boiler circulation system is made up of tubes, headers and drums connected together in a system that provides the flow of water to produce steam.
Water tubes have higher pressure and efficiency than shell tube boilers. These boilers can be of single or multi-cylinder type. This works very well.
type is placed horizontally to the hot source. The temperature in the type of order is very similar. When wind loads are high; The arrangement of the tubes is made at the end of the energy supply. Cross drum capacity ranges from 700kh/h to 240000 kg/
A Stirling boiler is a vertical boiler or straight tubes of water that run between the barrels and the coins and barrels of water. Helpfully, there are three banks of tubes in a four-reel layout.
These boilers come as package parts. It only needs steam, water pipes, fuel and electricity to run.
Boilers Pack a dark skin type with fire tube design to achieve high water transfer rates.
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