Jason Wayne Whaley

US Patent:

8534185, Sep 17, 2013

Filed:

Apr 23, 2008

Appl. No.:

12/596903

Inventors:

Andrew Dale Riley - Eufaula OK, US
Jason Whaley - Houston TX, US

Assignee:

National Oilwell Varco, L.P. - Houston TX

International Classification:

F04B 39/10

US Classification:

92185, 92112

Abstract:

A pump including a pressure compensated piston is disclosed. In some embodiments, the pump includes a piston with an annular body and an annular sealing element disposed radially outward of the annular body. The annular body has a radially-facing outer surface adjacent an inner surface of the sealing element and an axially-facing surface with an inlet port. A flowpath extends between the inlet port and the radially-facing outer surface of the annular body.