Two-plunger pump NV1BD1

On downstroke of the plungers in the area of the barrels, contained between the plungers, a rarefaction is created, that allows opening of the lower valve of the valve unit, and the formation fluid enters this area. The closed upper valve perceives the pressure of the fluid column and creates an extra downwarddirected load useful to overcome hydraulic resistance in the pump and friction forces in the sucker rod string. The latter is very important, as the main obstacle for pumping out highviscosity fluid is balking of the sucker rods because of excessive friction forces. The rod twoplunger pump with twostage compression, with a bottom lock is designed for pumping out of well highviscosity fluid (up to 0,3 Paos), containing up to 1,3 g/l of mechanical impurities.