CNG is an acronym for 'Compressed Natural Gas'. This is a fossil fuel that has taken millions of years of pressure and geological changes to be formed within the deep layers of the earth. While this gas is known to science as 'methane' it consist of hydrogen and carbon but is highly inflammable. This flammability of natural gas has caught the imagination of scientists who have successfully developed CNG conversion kits that enable vehicles to run on this powerful natural resource.
The size of the gas tank in the vehicle is not large enough to provide proper range if the gas is kept in its natural expanded form. It is for this reason, to allow the vehicle to move over a longer range that the CNG is compressed and stored in the CNG tanks, which are specifically designed to hold high pressure gas. Storing a tank load of compressed gas in a vehicle can put the scare into some people but it is much safer than having a tank full of liquid fuel – Petrol or Diesel.
It became imperative for technology to come up with an alternative 'and they did. Natural gas was compressed and used for heating, cooking and lighting for years but it was only with the development of the CNG conversion kits that it became possible to use natural gas to power vehicles.
This is how the CNG conversion kits use natural gas to power vehicles: The CNG is first compressed and stored in the vehicles compressed natural gas tank. From there it is injected into the combustion chamber through the carburetor. There is no need for the carburetor to vaporize the gas as it is already in a gaseous form. The carburetor has one primary function and that is to turn the liquid fuel into a vapor 'this process is called' atomization 'or' ionization '. With CNG this process is eliminated.
When the CNG leaves the tank it is cold and semi-liquid. This state has to be changed in order for the gas to combust in the chamber. In order to vaporize the gas completely the gas from the tank is fed into a diaphragm chamber that is hooked up with the engine cooling system through water pipes.
Since the engine water circulates through the radiator and the engine it is boiling hot. This water is circulated around a diaphragm in an air tight chamber. When the water heats the diaphragm it in turn heats the gas within. This increases the pressure of the gas and it is fed to the internal combustion engine through the carburetor.
The CNG conversion kits consist of a gas tank, a vaporizer, water pipes to circulate hot water from the engine around the diaphragm in the vaporizer, and a solenoid switch to change over from CNG to liquid fuel. When the gas leaves the tank it expands immediately and so it changes into a semi-liquid because this sudden change in pressure lowers the temperature drastically. The gas enters the leather diaphragm that is heated with the hot water on the outside vaporizing the gas instantly. This gas enters the engine through the carburetor and powers the engine.
Converting to CNG is easy and convenient by installing on of the branded CNG conversion kits however it may be mandatory in some states to seek written permission to do so from the relevant department. Whatever the red tape it is worthwhile to switch to CNG from Diesel or petrol.