A mechanism applies necessary forces for the creation of one or more plugs of compressible material to be supplied to a reactor. The plugs are capable of forming a seal between inlets for the plugs and the reactor. The mechanism includes two double-acting hydraulic piston cylinder assemblies coupled with two single-acting hydraulic piston cylinder assemblies.

A double-acting apparatus and method for manufacturing metal scrap compression materials, in which a variety of shapes of collected metal scrap are compressed into pieces having a standardized shape such that they can be directly loaded into a blast furnace, thereby enhancing productivity. Two compression chambers are disposed at both sides of a first compression cylinder such that metal scrap is loaded into the compression chambers. In particular, when one of first press plates moves forward inside a first compression space of one of the compression chambers, the other one of the first press plates moves backward and returns to an idle position.