PAC polyanionic cellulose drilling fluid and workover fluid are different.

PAC drilling fluids are polyanionic cellulose (PAC) chemicals added to drilling fluids. Polyanionic cellulose (PAC) is an anionic cellulose ether, which has the characteristics of high purity, high degree of substitution, and uniform distribution of substituents. In the drilling fluid system, PAC mainly plays the role of thickener, fluid loss reducer, and lubricant, which can improve suspension of drilling cuttings and migration of cuttings, reduce sticking, improve mud cake quality, and increase oil recovery. To prevent well collapse and blowout.

PAC workover fluid is a drilling fluid used for workover operations. Its main function is to protect oil and gas layers during workover operations, improve the flow conditions of oil and gas reservoir fluids between tubing and casing, and reduce damage to oil and gas layers.

Therefore, PAC drilling fluid and workover fluid are two different products, and the appropriate product needs to be selected according to different needs.