Locomotive type of boiler

The correct answer for the type of boiler that represents a locomotive is option 'D', which is a horizontal multi-tubular fire tube type boiler.

Horizontal multi-tubular fire tube type boiler

This type of boiler is commonly used in locomotives. It is designed to generate steam for the propulsion of a locomotive. Let's understand the features and working of a horizontal multi-tubular fire tube type boiler in detail.

Features of a horizontal multi-tubular fire tube type boiler:
- Horizontal arrangement: The boiler is horizontally arranged with multiple tubes running through it.
- Fire tubes: It consists of multiple fire tubes or flues that are surrounded by water in a shell. These tubes carry hot gases from the combustion chamber to the smokebox at the front of the boiler.
- Water space: The exterior of the fire tubes is surrounded by water, which absorbs heat from the hot gases.
- Water level indicator: A water level indicator is provided to monitor the water level inside the boiler.
- Safety valves: Safety valves are installed to ensure the safe operation of the boiler by releasing excess steam pressure.

Working of a horizontal multi-tubular fire tube type boiler:
- Fuel combustion: The fuel, such as coal or oil, is burned in the combustion chamber located at the rear end of the boiler.
- Heat transfer: The hot gases produced from the fuel combustion pass through the fire tubes, transferring heat to the surrounding water.
- Steam generation: As the water absorbs heat, it gets converted into steam. The generated steam is collected in the steam space above the water level.
- Steam circulation: The steam rises through the steam space and is collected in the steam dome. From there, it is supplied to the locomotive's cylinders for propulsion.
- Smokebox: The smokebox is located at the front end of the boiler and provides an exit for the exhaust gases after they pass through the fire tubes.

In conclusion, the locomotive type of boiler is a horizontal multi-tubular fire tube type boiler. It is designed to generate steam for locomotives by utilizing fire tubes to transfer heat from the combustion chamber to the surrounding water.