POSITIVE DISPLACEMENT PUMP INCLUDING A PLAIN BEARING FOR COMPONENTS EXPERIENCING AN OSCILLATING MOTION AT LOW SPEEDS

摘要

A positive displacement pump of this disclosure includes a plain bearing comprising a composite material located between a first component that may experience an oscillating motion at low speed (or at low speed and high loads) and a second component located about the first. The pump may be a mud pump configured to circulate a drilling fluid into and out of a well bore during an oil/gas well drilling operation. The first component may be a wrist pin of a crosshead and the second component may be an end of a connecting rod. The composite material may be a bearing grade material that is self-lubricating and wet or contaminant tolerant or resistant. The composite material may include polyketone. In retrofit or new applications, the plain bearing may include a sleeve containing a liner made of the composite material. No external lubrication may be required, eliminating the need for lubricating structures.