Abstract: A pumping unit for a well pump has a surface main cylinder with a main piston reciprocable therein, the piston having a connection to a standard well pump. In a flow cylinder of a relatively large diameter, a flow piston reciprocates within and divides the flow cylinder into a first flow chamber and a second flow chamber. The first flow chamber is in communication with the main cylinder. Air under pressure substantially to counterbalance the load on the well pump connection is supplied to the second flow chamber. There is a drive cylinder divided into a first drive chamber and a second drive chamber by a drive piston connected to but substantially smaller in diameter than the flow piston.

Abstract: A pumping jack for use with a well having a vertically reciprocable polish rod has a base including a horizontally extending table. A hydraulic cylinder is mounted on the base, with the cylinder axis extending parallel to and above the table. A plunger is reciprocable in the cylinder along the axis and carries with it a block including a first sheave around which a first flexible line is reeved. One end of the first line is affixed to the base, and the other end of the first line extends around a well sheave mounted on the base with the well sheave periphery tangent to the polish rod, the line from the well sheave being affixed to the polish rod. The reciprocating parts are balanced at least in part in either of two ways. In one way, there is a pneumatic chamber variable in volume in accordance with the reciprocation of the polymer and provided with air under an elevated pressure sufficient to counterbalance or offset part of the reciprocating load.

Abstract: A connector for use between two riser pipes has a pin fitting at the end of one pipe. An end sleeve on the pin fitting has a cylindrical exterior surface and a first peripheral flange with upper and lower normal surfaces. A box fitting is at the end of the other pipe and has an end box with a cylindrical inner surface engaging the cylindrical exterior surface of the pin fitting. A second peripheral flange on the box fitting has upper and lower normal surfaces and is adapted to abut the first flange. An annular nut is rotatable about the flanges and has interior threads engageable with exterior threads on a collar rotatable around the box fitting and abutting the second flange. An inturned, interrupted nut flange on the nut overlies the first flange, which is also interrupted. The nut flange and the first flange can be relatively rotated to pass each other axially or to prevent such axial movement.