A muffler is a JASMA authorization article or safety standard conformity article.

Various roles of an exhaust system which does not come out as sound is suppressed.
As for エキゾーストシステム, all the passages after exhaust gas comes out of an engine refer to a way. exhaust gas is collected and it is made to flow out smoothly The catalyst which begins from a エキゾーストマニ hold and makes exhaust gas clean, the muffler in which there is small exhaust sound, and it ら -- it consists of the exhaust pipe to connect and the tail pipe which determines the exit of an exhaust gas.
Of course, the main work of a muffler should lower exhaust sound. It is necessary to lower the pressure and temperature of exhaust gas to it.
The exhaust valve of an engine cylinder If it opens, the exhaust gas with big pressure will expand rapidly, will make air use, and will make a loud sound. It is 振 of air as "sound". Since it is 動, sound will also become small if change of pressure is made small. Then, in the room of a metal called a muffler, it is gradually. It is made to expand, and pressure is lowered gradually, or the waves of pressure are thrown at each other, and there is small sound.
Moreover, since exhaust gas becomes a maximum of 900 degrees C or more, if it emits into the around 20-degree C atmosphere as it is, it will expand rapidly. It carries out and this and a loud sound are made. To then, the thing for which エキゾーストシステム long in making it expand by a muffler is passed Therefore temperature is lowered gradually and a difference of temperature with the atmosphere is made small.
System 全 As the body, there is also a role of "leading to the place which aimed at exhaust gas." the straw matting with which it is troublesome to a pedestrian etc. with straw matting if it has turned to the left, and an exhaust gas invades during a run in the car depending on the position of a tail pipe, or direction -- ある.
　
"A Japanese automobile muffler association" calls it JASMA for short. He is the organization which the makers who are making the muffler for aftermarkets gathered and was formed in 1989.
In JASMA, it has approved attaching an authorization certificate only to what the product for which the maker who joins applied established [ whether there is any conformity to the safety standard, and ] the original standard, and tested and passed with the public testing body etc., and attaching issue and a JASMA authorization plate to a product.
Since notice [ article / authorization ] is submitted to a transportation office or Land Transport Office in advance, also when it goes to receive government-operated auto inspection, it OKs only by showing authorization and the certificate of JASMA. When receiving an automobile inspection by Diller, if parts other than an original manufacturer's product are attached, it may not receive, but such worries of JASMA authorization products are also unnecessary.
Also in car accessories, a muffler is one of the articles of consumption. Although based also on how to ride, an automaker pure muffler is only about 50,000km, it rusts and a hole opens. Even if the hole is open to the muffler, a car runs, but こっれ is fairly dangerous. If the engine was started, it carried out without っぱ and you are sleeping in the train, since the hole was open to the muffler, an exhaust gas invades into in the car, and the accident in which it dies from carbon monoxide poisoning is also coming. If "? with a strange exhaust sound" is thought, an exhaust system will be checked immediately. Probably, it will be better to exchange a little early, if the hole is open.
Since being sold at suggested prices by a dealer is most, a pure muffler is fairly high. There is that it is also cheaper to buy the object for aftermarkets in a car shop etc. If it is a JASMA authorization muffler, it can be used feeling easy rightly.
　
A muffler is a JASMA authorization article or safety standard conformity article.