A vertically orientated hydraulically driven oilfield lift pump unit having a simplified hydraulic system. The system uses a pair of single acting hydraulic cylinders (18) in tandem with a pair of double acting hydraulic cylinders (20) interacting with hydraulic accumulators (58,60) to provide an energy efficient, robust hydraulic system design with a minimum number of components.
申请公布号
WO2010141405(A3)
申请公布日期
2011.03.31
申请号
WO2010US36807
申请日期
2010.06.01
申请人
NATIONAL OILWELL VARCO L.P.;LORIMER, GERRY, L.;BLAQUIERE, DENIS
