Design Of Sucker Rod Pumping System In Low Permeability Reservoir

With the constant exploitation of low permeability reservoir,the sucker rod pumping equipment has been widely used in its production.Having marked difference with high permeability zone,low permeability reservoir shows bad physical property as well as high filtrational resistance,and its filtrarional pattern disobey Darcy`s law.For low production and high gas fluid ratio well,there are always many problems,such as illogical producing pressure drop,unequilibrated supply and production,low lifting rate and so on.Just because of the problems above,it makes it essential that we should find out applicable theory to analysis infow performance relationship,defining reasonable producing pressure,and make a optimizing sucker rod pumping system design.In view of water controlled low permeability reservoir,this paper build a three-phase infow performance relationship including oil,gas and water,and it lays a foundation for defining a proper proper producing pressure.In the paper,we divide the well into three parts,gas column part,oil column part and gas-liquid phase column part,thus we establish a geometric model for pressure distribution of the well.Whether considering installating a gas-anchor,the paper gives the regular pattern of the pump volumetric efficiency,obtaining the pump-separator performance curve,thus clear-cut the requirement and method im improving the pump efficiency.Finally,adopting simplified calculation and uniform strength rule,the paper designs the combined string for a low permeability well,optimizes its swabbing parameter,making the rod pumping system runs efficiently under proper working system.