Abstract: A drive system for a pump includes a housing and a fluid displacer and a reciprocator configured to mechanically displace the fluid displacer through respective suction strokes. The housing and fluid displacer define an internal pressure chamber configured to be filled with a working fluid having a charge pressure. The internal pressure chamber is configured such that the working fluid exerts the charge pressure on the fluid displacer during both the suction stroke and a pressure stroke of the fluid displacer.

Abstract: A post assembly for a hollow post includes an elongated support, preferably a standard pipe, at least one fixture, and, optionally, a mount. The fixture includes a fitting having a bore for receiving the elongated support, and a web that extends from the fitting to support a plurality of friction plates adapted to engage the inner walls of the hollow post. When employed, the mount allows for adjustment of the vertical alignment of the elongated support. The elongated support is attached to a bracket which is positioned over a base having a plurality of members extending upward through holes in the bracket. Movement of adjustment members positioned between the base and bracket allow for adjustment of the angle of the elongated support. A method of installation using the fixtures and mounts of the invention is also provided.

Abstract: A post assembly for a hollow post includes an elongated support, preferably a standard pipe, at least one fixture, and, optionally, a mount. The fixture includes a fitting having a bore for receiving the elongated support, and a web that extends from the fitting to support a plurality of friction plates adapted to engage the inner walls of the hollow post. When employed, the mount allows for adjustment of the vertical alignment of the elongated support. The elongated support is attached to a bracket which is positioned over a base having a plurality of members extending upward through holes in the bracket. Movement of adjustment members positioned between the base and bracket allow for adjustment of the angle of the elongated support. A method of installation using the fixtures and mounts of the invention is also provided.