A measure of volume for petroleum products in the united states.
One barrel is the equivalent of 42 u.s.
Gallons or 0.15899 cubic meters (9,702 cubic inches).
One cubic meter equals 6.2897 barrels.
The cylindrical part of a sucker rod pump in which the piston-like plunger moves up and down.
Operating as a piston inside a cylinder, the plunger and barrel create pressure energy to lift well fluids to the surface.