Abstract: With the existence of the wall slip, the resistance testing principle is analyzed. The testing system and resistance calculation are also studied. To test the resistance characteristic of lubricating grease and to eliminate the effect of wall slip, the flow equation without wall slip which is independent of pipe diameters is set up by applying the Mooney method. In order to reduce wall slip and non-coincidence of flow curves due to the factors such as viscoelasticity and thixotropy, the tube rheometer testing system and reasonable experimentation are established. Experiments have verified the validity of the flow equation established. The approximate solution for the resistance to the flow equation is obtained. The difference between approximate solution and precise solution is reduced by 3D optimized calulation. The study results will provide an academic and experimental foundation for pipe transportation of centralized lubricating system.

Key words: Lubricating grease, Pipe-flow, Resistance characteristic, Testing system, Wall slip