Shear pump is a kind of special used for effective shear polymer and clay, and shear pump has been confirmed by field use and theory. In the drilling fluid system, polymer (or clay) should be fully shear in advance and then inject into the drilling fluid system, Those can give full play to its effectiveness, and improve the drilling performance. If there is no sufficient shear, polymer in the first cycle could jam sieve net, lose a massive amount of polymer, to increase the drilling cost, and may also make the large size of solid phased particles in drilling fluid hard and difficult to remove. Shear pump for polymer (or clay) can provide fast shear for polymer (or clay), shear pump can solve problems which is caused by poor hydration and prominent when polymer (or clay) in drilling fluid and completion fluid. At the same time, the use of shear pump can make the polymer injection amount reduced by more than 15%, the dosage of bentonite reduced by more than 30%, and improve the mud cake and fluid flow loss, reduce drilling fluid shear rate, improve the gel strength, and it has reached the lead level to similar foreign products, the shaft seal structure is more reliable, excellent performance, the use of maintenance more convenient.
The work principles of the centrifugal pump impeller rotation and generated the centrifugal force by the water to work. Before the centrifugal pump start, it is necessary to make the pump casing and suction tube filled with water, and then starts the motor, make the water pump shaft to drive the impeller for high speed rotation and make the water flow into the volute pump.
Difference between shear pump and centrifugal pump is mainly deferent in their each work principle, application and they both have their own advantages, Centrifugal pump is compact structure, wide range, flow and range applicable to mildly corrosive liquid. Centrifugal pump has a variety of control options, uniform flow, smooth operation, low vibration, etc, and does not require special shock absorption. Maintenance cost is very low in equipment installation and maintenance. Shear pump suction and discharge process is similar to centrifugal pump, the difference is in the configuration of mud, after impeller of high speed rotating drilling fluid pressure in the four funnel, ejected by 44 nozzle flow and blade out liquid flow impact to 90 degrees, make polymer shear, refinement, mixed, to speed up the polymer and moving soil particle dispersion, saving the hydration time to improve the dissolution rate of additive, reached the rheological properties of mud required quickly. Shear pump has large displacement, high lift, aspiration is good, high efficiency, etc, can satisfy with the configuration and the status quo of the low pressure job. Shear pump hsa made elaborate design for mechanical seal and oil seal, greatly extend the service life.