Kerosene lamp
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A kerosene lamp, widely known in Britain as a paraffin lamp, is any type of lighting device which uses kerosene (paraffin) as a fuel. There are two main types of kerosene lamp which work in different ways, the "wick lamp" and the "pressure lamp".
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Wick lamp
A wick lamp is a simple type of kerosene lamp which works in a similar way to a candle. This type of lamp is also known as an "Oil lamp". In a wick lamp there is a small fuel tank at the bottom of the lamp. There is also a wick, usually made of cotton. The lower half of the wick is dipped into and absorbs the kerosene. The top part of the wick extends out of the top of fuel tank and (usually) a wick adjustment mechanism.
When the top part of wick is lit, the kerosene which has been absorbed in the wick burns and produces a yellowy flame. As the kerosene is burnt, capillary action inside the wick draws more kerosene up from the fuel tank to be burnt.
On this type of lamp, the size of the flame can be controlled by adjusting how much of the wick extends out of the top of the fuel tank. This is usually done by means of a small knob that operates a toothed metal disk that bears against the wick like a sprocket wheel. If the wick is turned up too high the lamp will produce smoke (unburned carbon soot). The flame is usually protected by some kind of glass screen, shade, or globe. The glass acts to prevent the flame from being blown out, to prevent the flame from being an excessive fire hazard, and also to enhance the thermally-induced draft. The draft carries more air (oxygen) past the flame, helping to produce a brighter light than would be produced by an open flame.
This type of lamp produces only a dim yellow light and is not much brighter than a candle. Wick lamps can also be quite smelly if they are not burning well. Except for decorative purposes or emergency lighting, wick lamps are rarely used today, but were popular before the advent of electrical lighting became widespread. They were first used by Ignacy Łukasiewicz in 1853, the year that is accepted as the starting day of modern oil industry.
Pressure lamp
This type of lamp is far more sophisticated than a wick lamp and produces a much brighter light, although they can be quite complicated and fiddly to use. This type of lamp is commonly known in the UK as a "Tilley lamp" after a manufacturer of the same name.
A pressure lamp has a fuel tank at the bottom with a small pump to pressurise the kerosene. There is a narrow gap up to the top of the lamp called a flu, and at the top of the lamp there is a burner (gas outlet). Directly underneath the burner is the mantle, a fabric bag coated with chemicals which incandesce (glow brightly) when heated by the gas flame.
To work a pressure lamp the kerosene needs to be heated to the point where it is vaporised. This is necessary because vaporised kerosene burns much hotter than liquid kerosene.
The kerosene burner has to be heated by means of a Primer, usually Methylated spirit, which is burnt in a small tray underneath the burner to heat it. The kerosene in the tank is then forced into the burner, which is done by pumping up the air pressure in the fuel tank. This causes the kerosene to be forced upwards through the flu.
After the primer has stopped burning, the flames from the primer should have got the burner hot enough to vaporise the kerosene. When a valve is opened the pressurised kerosene is forced into the hot burner where it is vaporised. This kerosene vapour is then directed downwards into the mantle where it burns hot enough to make the mantle glow and produce a bright white light. The heat from the burning vapour in turn vaporises the liquid kerosene which is being forced into the burner.
This type of lamp is popular amongst campers and people who like outdoor activities. Gasoline-burning lamps have also been produced; these do not require any primer liquid. However, both have lost out in popularity in recent years to portable lamps which burn Butane or Propane gas as these are easier to use, although more expensive to run. In the United States, the Coleman Company is perhaps the most famous producer of all four types of lamps.
There are portable kerosene stoves which work in much the same way as pressure lamps.
See also
External links
- pressure lamp website (http://homepage.ntlworld.com/munwai/index.htm)