Convert from hogshead [US] to drum [US, petroleum]

Unit Definition (hogshead [US])
The hogshead [US] is a traditional unit of volume for liquids. Originally the hogshead varied with the contents, often being equal to 48 gallons of ale; 54 of beer; 60 of cider; 63 of oil, honey, or wine; or 100 of molasses. In the United States, a hogshead is defined to hold 2 barrels, or 63 gallons; this was the traditional British wine hogshead. It is equal to exactly 14 553 cubic inches, or about 8.422 cubic feet (238.48 liters). The British imperial and American hogsheads are almost exactly the same size. No one seems to know for sure how this unit got its unusual name.

Unit Definition (drum [US, petroleum])
The drum [US, petroleum] is a unit of volume sometimes used in the oil trade. The traditional standard drum of oil contains 55 U.S. gallons or about 208.198 liters. One 55-gallon drum equals 1.3095 barrels.