Convert from ounce [US, liquid] to drum [US, petroleum]

Unit Definition (ounce [US, liquid])
The ounce [US, liquid] is a traditional unit of liquid volume, also called the fluid ounce to avoid confusion with the weight ounce. In the U. S. customary system there are 16 fluid ounces in a pint, so each fluid ounce represents 1.804 687 cubic inches or 29.573 531 milliliters. A U.S. fluid ounce of water weighs just a bit more than one ounce avoirdupois.

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.