What is a Steam Boiler – Working Principle, Types of Steam Boilers

Generally, a steam boiler is a type of closed container, designed with steel for heating the water to generate steam by some energy source like burning of fuel with eventually. The vapor generated may be delivered at low-pressure for the industrial progression work in sugar industries, cotton mills, and for generating steaming water that can be utilized for heat up fixing at much low-force. The capacity of the boiler should have ten liters of water and the working pressure must be 3.4 Kgf/cm2 (kilogram-force). This article discusses what is a steam boiler and its types used in power stations for generating steam.

What is a Steam Boiler?

A steam boiler is a power generation device, used for generating steam by applying the heat energy to water. The pressure range of earlier boilers ranges from low pressure to medium pressure (7 kPa to 2000 kPa/ 1psi to 290 psi). The present boilers are more useful because it works with high pressure than old ones. This boiler is very used whenever a steam source is necessary, and the size, type mainly depends on the type of application like mobile steam engines which includes handy engines, steam locomotives, and road vehicles. These vehicles include a mini boiler that can be worked with steam power. Generally, power stations or stationary steam engines have a separate large steam generating capacity.

Steam Boiler
Steam Boiler

The Function of Steam Boiler

The main function of a steam boiler is to producing, storing and troubling the vapor. The liquid contained boiler is nothing but a shell and the heat energy produced while burning of fuel will be moved to water, and then it converts into steam at the required pressure as well as temperature.

The main conditions of this boiler mainly include the water container should lock very carefully. The vapor of water should be supplied in the preferred conditions namely, quality, rate, pressure, and temperature.

Steam Boiler Working Principle

The main working principle of a steam boiler is easy. This boiler is one type of closed device in the shape of a cylindrical.  The capacity of the boiler to have steam, as well as water is sufficient.

Generally, the liquids are stored in the boiler for generating steam by burning the fuels or applying the heat energy at different conditions of pressure based on the size of the vessel as well as specifications. Finally, the steam in the boiler supplies using a pipe and flows into various industries like plants.


The main components of this boiler mainly include a shell, furnace, grate, mountings, water space, accessories, refectory, level of water, scale, foaming, lagging, and blowing off

Steam Boiler Types

The steam boilers are classified into several types based on its requirement

Water Tube Boiler

The water tube boiler is one type of boiler, and the main function of this boiler is the water in the tube will be heated to generate the vapor. The main benefits of this boiler are, used in huge thermal power-stations. By using a number of water tubes a big heating surface can be attained. The water movement is much faster, so the heat transfer rate is very high which consequences to high-efficiency. This type of boilers requires fresh water as well as water treatment plants to maintain the necessary quality of water tube boiler.

Water Tube Boiler
Water Tube Boiler

Fire Tube Boiler

This type of boiler can be built with a number of tubes for supplying the hot gases.  These tubes are absorbed into water in a closed container. Actually, this type of boiler consists of a single closed container to pass the hot tubes. These tubes are heated up the water to convert into vapor and the vapor remains in the similar container. When both the water as well as vapor is in a similar container, then a fire-tube boiler cannot generate vapor at high force. In general, it can generate the utmost 17.5 kg/cm2 & with a 9 Metric Ton capacity of steam for each hour.

Fire Tube Boiler
Fire Tube Boiler

Package Boiler

A packaged boiler is a separate application which is used to get the energy from an incorporated burner with fueled by oil or gas. This type of boiler is proficient in producing huge steam output at a high-pressure as well as high-temperature. This boiler operates variable loads which have a small start-up or response time. The applications of this boiler mainly include process steam for industrial, chemical or used as power generator with a steam turbine. The package boiler can be used as a peak-load boiler because of an addition to another power that kicks in while other supplies not succeed.

Packaged Boiler
Packaged Boiler

Stoker Fired Boiler

The stoker fired boiler is most capable in common range and cogeneration systems in sugar factories. These boilers have membrane design and operate completely automatic. These Boilers have intrinsic features for the operation of trouble-free and high-thermal efficiency. These are classified based on the technique of supply fuel to the boiler & with the grate type. The stoker-fired boilers are classified into two types namely chain-gate or traveling grate stoker and spreader stoker.

Advantages of Steam Boiler

The advantages of this boiler include the following.

  • The construction cost of these boilers is low.
  • This boiler uses any kind of chimney
  • It occupies less floor area.
  • It is portable.
  • It has a self-enclosed boiler

 Disadvantages of Steam Boiler

The disadvantages of this boiler include the following.

  • The design of the steam boiler is vertical so the capacity of steam rising is low.
  • It has limited pressure and capacity.
  • The cleaning and examination of these are difficult.
  • It requires high headspace

Applications of Steam Boiler

The applications of this boiler include the following.

  • These are used to generate power in steam turbines or engines.
  • These are used for various processes in process industries
  • These are used in houses or buildings in cool weather for generating a hot water supply

Characteristics of Steam Boiler

The characteristics of steam boiler include the following.

  • Steam boiler generates the highest amount of steam with low fuel utilization.
  • It must be less weight as well as needs small space
  • It must be immediate starting.
  • These boilers must be cheap as well as needless concentration.
  • These boilers handle any kind of fluctuating load.

Thus, this is all about the steam boiler and its types. From the above information, finally, we can conclude that it plays an essential role in power plant working. These are used for the production of electricity where steam turbines are utilized in power plants. Here is a question for you, what is the main purpose of the steam boiler?