Abstract: A pneumatic testing apparatus is provided for accelerating a mass. The apparatus has a housing defining a reservoir and a cylinder having an opened proximate end and a closed distal end. The opened proximate end is positioned within the reservoir and a piston is positioned in the cylinder. The piston has a first side and a second side. A shaft connects to the first side of the piston, the shaft being positioned coaxially within the cylinder and extending through its closed distal end. An exhaust orifice is located at the closed distal end, wherein the mass is positioned on the portion of the shaft extending from the distal end of said cylinder and is accelerated as a gas at a first pressure located in the reservoir enters the open proximate end of the cylinder and urges against the second side of said piston, thereby causing the piston to accelerate toward the distal end of the cylinder and simultaneously accelerate the mass.

Abstract: A pneumatic testing apparatus is provided for accelerating a mass. The apparatus has a housing defining a reservoir and a cylinder having an opened proximate end and a closed distal end. The opened proximate end is positioned within the reservoir and a piston is positioned in the cylinder. The piston has a first side and a second side. A shaft connects to the first side of the piston, the shaft being positioned coaxially within the cylinder and extending through its closed distal end. An exhaust orifice is located at the closed distal end, wherein the mass is positioned on the portion of the shaft extending from the distal end of said cylinder and is accelerated as a gas at a first pressure located in the reservoir enters the open proximate end of the cylinder and urges against the second side of said piston, thereby causing the piston to accelerate toward the distal end of the cylinder and simultaneously accelerate the mass.

Abstract: A casing gas pump is reciprocated by the pump jack of an oil well. Push rods slidable within rigid vertical cylinders are connected by a bridle bracket to bridle cables depended from the pump jack horsehead. Vertical reciprocation of the horsehead moves pump leathers connected to the push rods up and down within cylinder bores. The cylinders are vertical, non-pivoting and fluidly connected to a header. The header is connected to the annulus of the well and to a gas line. Check valves prevent back flow from the header into the annulus and from the gas line into the header. The pump leathers form reciprocating pistons that are formed and assembled to avoid pulling a vacuum on the annulus.