Abstract: An apparatus to compress a fluid is disclosed herein. The example apparatus includes a casing, an actuation cylinder and a compression cylinder defined in the casing, a rod slidably coupled between the actuation cylinder and the compression cylinder, and a piston coupled to the rod at an end of the rod, the end of the rod in the compression cylinder, the piston slidable relative to the compression cylinder to compress the fluid therein.

Abstract: An apparatus to transfer a fluid from a fluid inlet to a fluid outlet is disclosed herein. An example apparatus includes a first compressor unit and a second compressor unit fluidly coupled between the first and second locations, and a valve coupled between the first and second compressor units, the valve to switch between a first state and a second state, the fluid to flow through the first and second compressor units in a parallel configuration when the valve is in the first state, the fluid to flow through the first and second compressor units in a series configuration when the valve is in the second state.