Design and Performance Analysis of a New Variable Friction Pipeline Magnetic Flux Leakage Detection Robot

To meet the requirements of in-pipeline inspection tasks, this paper designs a fluid-driven pipeline magnetic flux leakage (MFL) inspection robot with controllable speed. Based on the operating conditions of the robot, a combined solution with variable friction and drainage speed regulation devices is developed. A mechanical equilibrium model of the robot is established. Through theoretical calculations and ANSYS 19.0 simulations, the structural parameters of the cup seals are determined. FLUENT fluid simulations are employed to optimize the drainage area, and the relationships between the valve opening, flow velocity, and torque are analyzed. Furthermore, the speed regulation characteristics of the variable friction device are evaluated. Experimental results demonstrate that the robot can achieve effective speed control and possesses reliable anti-jamming capability. The findings confirm the feasibility of the designed robot for pipeline magnetic flux leakage inspection tasks.