Partially hydrolyzed polyacrylamide Hp is often used, which is obtained from the hydrolysis of polyacrylamide. Its function is to adjust the rheological property of drilling fluid, carry cuttings, lubricate drill bit, reduce fluid loss and so on. With PAM modulation of drilling mud weight is low, can reduce the pressure of the oil and gas layer and congestion, easy to find oil and gas layer, and is helpful for drilling, drilling speed is higher than conventional mud 19%, abou...