What is a Simple Vertical Boiler?
A simple vertical boiler is one whose axis of orientation is vertical with respect to the ground. it is a fire tube or a water tube boiler.
A vertical boiler is a type of fire-tube or water-tube boiler where the boiler barrel is oriented vertically instead of the more common horizontal orientation. Vertical boilers were used for a variety of steam-powered vehicles and other mobile machines, including early steam locomotives.
It consists of a cylindrical shell surround by a vertical cylindrical box name called the firebox. This is slightly tapered towards the top of the shell to allow ready passage of the steam to the surface. At the bottom of the firebox, is a grate.
The firebox is fitted with two or more inclined cross tubes. These tubes are used to increase the heating surface of a simple vertical boiler and also increase water circulation. At the top of the firebox, there is a stack (Produce Natural Draught). Hand holes are provided at the end of cross tubes to clean them.
A manhole is also available at the top of the shell for a man to enter the boiler for cleaning or maintenance. A mud hole is provided at the bottom of the shell to remove the mud that settles down. The space between the boiler shell and firebox is filled with water to be heated.
Tubular gauge glass is also provided to see the water level inside the boiler. Pressure gauge, safety valve, air vent valve, and steam supply valves are also installed there at the top of the crown plate.
Parts of a Simple Vertical Boiler
- Vertical Cylindrical Shell: This is the outermost cylindrical vertical shell of the boiler. Other parts of the boiler are inside this part. Most of the part of this cylindrical shell is filled with water and the rest part is for steam.
- Cross Tubes: One or more cross tubes are riveted or flanged to increase the heating surface and to improve water circulations.
- Furnace (or Firebox): Furnace is used for the combustion of the coal. Coal is burnt here to produce heat.
- Grate: It is present at the bottom of the furnace. It is the place in the furnace where coals are placed.
- Fire Door or Fire Hole: Coal is inserted in the furnace through this hole or door.
- Ashpit: It is available in the boiler to collect the ash deposited by the furnace.
- Hand Holes: Hand Holes are present in the boiler opposite to the end of each cross tubes for cleaning the cross tubes.
- Chimney: A chimney is a vertical cylindrical pipe that extends from the top of the firebox to 1the top of the shell. It is used to pass the smoke from the boiler to the atmosphere.
How does Simple Vertical Boiler Work?
In a simple vertical boiler, fuel is added through the fire hoke into the grate which burns there to produce the hot gases. fuel when converted into ash is collected into the ash pit.
The boiler diameter is normally 3 feet and 9 inches to 5 feet and its height is 9 feet. each cross tube has a diameter of 9 inches. The boiler heating surface is 80 feet square and its grate area is 8.4 feet square. The boiler pressure is 100 PSI.
The combustion gas flows from the furnace and passes around the tubes. These gasses escape to the atmosphere through the chimney. Due to natural circulation water heats up and steam production starts. steam which produces as a result of water heating is collected at the steam space of the boiler. steam is collected until a certain pressure is attained and then steam is passed out for use like running a turbine or engine.
Application of simple vertical boiler
- Simple vertical boiler has may application is railway locomotives for example railway steam engine
- Simple vertical boiler is used in the road vehicles like steam wagon (steam lorry or steam wagon)
- Simple vertical boiler has a very famous application that steam tractor
- There are number of boats especially smaller one which uses the simple vertical boiler to power the engine
- In some parts of the world simple vertical boiler are used in steam donkeys
- Simple vertical boilers are also used in the steam cranes and steam shovels
Advantages of simple vertical boiler
- low initial cost because of lesser parts
- Low maintenance cost
- Simple working
- Easy to install and replace
- Occupy small space on ground
- Simple vertical boiler has water level tolerance
Disadvantages of simple vertical boiler
- Vertical design limits its working in many places
- Because of the limited grate area steam production is limited
- Impurities settle down at the bottom thus prevent water from heating
- Boiler tubes must be kept short to minimize height. As a result, much of the available heat is lost through the chimney, as it has too little time to heat the tubes.