Exhaust pipe

An exhaust pipe is usually tubing used to guide waste exhaust gases away from a controlled combustion inside an engine or stove.

An exhaust pipe must be carefully designed to carry toxic and/or noxious gases away from the users of the machine. Indoor generators and furnaces can quickly fill an enclosed space with carbon monoxide or other poisonous exhaust gases if they are not properly vented to the outdoors. Also, the gases from most types of machine are very hot; the pipe must be heat-resistant, and it must not pass through or near anything which can burn or can be damaged by heat. A chimney serves as an exhaust pipe in a stationary structure.


With a ship's or large boat's onboard below-decks diesel engine:-

* Lagging the exhaust pipe stops it from overheating the engine room where people must work to service the engine.

* Feeding water into the exhaust pipe cools the exhaust gas and thus lessens the back-pressure at the engine's cylinders' exhaust ports and thus helps the cylinders to empty quicker.

An automobile's exhaust system usually connects to the exhaust manifold and usually includes a muffler (British English: silencer) to reduce engine noise, and often in recent years a catalytic converter to reduce the emissions that contribute to air pollution.

In a two-stroke engine, such as that used on dirt bikes, a bulge in the exhaust pipe known as an expansion chamber uses the pressure of the exhaust to create a pump that squeezes more air and fuel into the cylinder during the intake stroke. This provides greater power and fuel efficiency.

On a two-cylinder motorcycle, "siamese exhaust pipes" are where both cylinders blow into the same exhaust pipe. This usage is derived from "Siamese twin".

Most motorcycles' exhaust pipes and their silencers/mufflers, and the heat shields around some trucks' exhaust pipes, are chrome plated and act as display features.