For the heavy oil recovery, Shengji has developed a series pumps. The double plunger mechanical valve pump is one of them. This pump adopts double plunger mechanical valve structure. There are two separate plungers, upper plunger and lower plunger.

The travelling valve is a mechanical structure; it takes up and down movement with sucker rod. It separates the press and sealing function of the plunger, which increases the pump service life greatly. The plunger adopts a floating structure, which has self-healing function and improves the valve life.

This pump can prevent gas lock while enhancing the pump effect. So, this kind of pump is suitable for cold production in the heavy oil well (the oil viscosity does not surpass the 4000 mPa·S), and it can also be used in the gas well, where the gas-oil ration below 800. Furthermore, in the deviated well, this pump also has a good performance.