(It is 4.54609L per gallon, so 1 barrel is about 190L).
It has become a crude oil trading unit adopted all over the world.
Crude oil trading is not calculated by weight, but by volume. ...
The density of oil is not fixed, generally between 0.75- 1.
When Rockefeller established the Standard Oil Company in 1870, he used a lot of wooden barrels produced by his family. 1 has a self-supporting delivery specification of 42 gallons, and the barrel is painted blue to distinguish it from other manufacturers. At that time, the oil trade was based on barrels, and oil companies extracted oil from different oil plants, and the amount of each barrel was different. There is no standard for the government to announce prices and taxes, so it has become a top priority for oil buyers and sellers and government tax authorities as a third party. So before the 1876 civil war, the United States adopted a standard acceptable to both British and American businessmen, and set 42 gallons as 6544. This standard unit barrel for oil measurement (4.54609L per gallon, so 1 barrel is about 190L) has become a crude oil trading unit adopted all over the world.