SA179 Tubes

Working principle Of Water tube Boiler

A high-pressure water tube boiler (also known as water-tube or water tube) circulates water in tubes heated externally by a fire. The furnace burns fuel, creating hot gas that boils water in the steam-generating tubes.

The heated water/steam mixture is then pumped into the steam drum. Saturated steam is drawn from the top of the drum. Steam passes through tubes in the hot gas path to become superheated in some services. Steam that is heated above the boiling point at a given pressure is known as superheated steam. Due to the fact that superheated steam is a dry gas, it is typically used to operate turbines, since water droplets can severely damage the blades.

Speaking of Boiler Tubes , specialised boiler tubes are utilised in proper functioning of Boiler Tube. Is one leading Manufacturer, Supplier & Stockist Of Seamless A213 & SA213 T22 Tubes.

Water tube boilers are mainly used to generate steam with high temperature and pressure. An internal structure of this boiler consists of a small steam drum and narrow tubes. In this boiler, high-volume vapour is produced for high-capacity applications. There are several reasons why these boilers have replaced fire tubes such as their lighter weight, faster steam production process, custom design, and high efficiency. In earlier water tubes, the only drum is connected to the headers by short, straight tubes and bent pipes. Hot gases flow only once through these pipes. An overview of water tube boilers, their components, and types is presented here.

Types Of Water Tube Boilers.

Three types of watertube boilers exist, each with a different shape.


The steam and water drums are stacked one above the other in this boiler. Water pipes are curved between the drums, forming an O shape.


The water drum sends water to the generating tubes, which are part of the fire box. Water is boiled into steam and rises into the steam drum, then into the steam header.


There are two water drums in this boiler. Using a shared header, the contents of the two water drums are boiled and sent up generating tubes into the steam drum, then to the steam header.

Water Tube Boiler Components

  • Boiler Shell: This shell is the external cylindrical part of a pressure container.
  • Steam drum: It is a collection vessel for steam and water.
  • Mud drum: This is a cylindrical formed space at the base of the water space. It will gather impurities like mud, sediment, and others.
  • Water walls: It is a tubing arrangement around the furnace to extract heat from fuel to generate steam.
  • Furnace: An enclosed space provided for the combustion of fuel.
  • Safety valve: It finds a use for stopping the unnecessary force from the construction of a boiler.
  • Strainer: This is a type of device as a filter to hold solid elements and let a fluid supply.
  • Sight glass: A glass tube is utilised on steam type boilers for giving observable signs of the water level in boilers.
  • Steam stop valve: It controls the steam flow supply outside.
  • Feed check valve: The high-force water flows via this valve, which releases to the boiler simply and supplies the water to the water type boiler.
  • Burner: This is one type of device for the beginning of air and fuel into a boiler at the preferred velocity. It is the most crucial apparatus for the firing of gas or oil.
  • Economizer: Accessory used to recover the heat of flue gas that leaves the boiler by heating feed water.
  • Superheater: It finds use to increase the temperature of the steam.

Working Principle of Water Tube Boiler

A water tube boiler works by thermal syphoning (circulation of natural water). This type of boiler consists of two drums, namely the steam drum and the lower drum.


Below is a diagram of a water tube boiler, which shows how two drums are connected via a riser and a downcomer. First, water is pumped into the steam type drum using a water pump. Whenever the fuel is burned, hot gases are generated that can be supplied into the boiler’s shell. Hot gases produced by the fuel will replace heat with water; the water will be transformed into steam. The concentration will automatically increase as the water temperature rises.


Water from the steam drum will be fed into the mud drum via the downcomer tube as well as used to heat the water in the mud drum. When cooler supply water is introduced into a steam type drum due to the high concentration of cool water, it moves down in a downcomer type tube near the mud drum.

Transferring hot water from a mud drum to a steam drum using riser tubes results in normal water circulation in a water tube boiler. Whenever more steam is generated in the boiler, the force in the drum increases & the water supply into the drum decreases, reducing the steam flow. Additionally, when the steam production rate decreases, the force in the water-tube boiler decreases, and the water supply into the boiler increases, which also tends to increase production. The water tube boiler controls steam production in a similar way. is a leading supplier, stockist, manufacturer & exporter of Seamless A213 & SA213 T22 Tubes. Get in touch with us for the best rates & availability.

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