Function and Usage of Polyacrylamide for Drilling Fluid 1. Flocculation Effect: The product can flocculate drill cuttings and clay in drilling fluid. 2. Lubricating Effect: The product can be absorbed on the surface of metal or clay particles to form liquid film to change friction on the solid surface into liquid frication, thereby lubricating drill bits and drills, lowering the mud cake frication coefficient, and reducing underground accidents. 3. Leakage Plugging Effect: The product can generate crosslinking under the effect of A 13+, Fe 3+, Ca2+ and other ions, a part of high molecular compound is changed from linear shape into body shapes, the product is not water-soluble, and can be adsorbed on the well wall to plug ground layer gaps and to prevent leakage of drilling fluid. 4. Filter Loss Reducing Effect: The hydrolyzing degree of the product is higher, the hydration radicals on the molecular chains are more, hydration is better, and it changes flocculating agent into filter loss reducing agent. 5. The product can form space net rack structures with clay particles in drilling fluid, the effective viscosity is lowered along the increase of shear dilution speed, and the product has excellent shear dilution effect. Physical/chemical Index Item Indicator Solid >=90 Purity >=90 Fineness (0.9mm weight of screen residue) >=10 Molecular Weight Ten-thousand 300-500 Degree of Hydrolysis % 25-35 Performance Indicator of Drilling Fluid Item Indicator Flocculation Time <=40.0 Fluid Loss Reducing Rate >=30.0