To address the challenges of complex sensor calibration procedures and workpiece placement eccentricity in online 3D geometric parameter measurement of train wheels, this study proposes a high-precision measurement system based on multiple line laser sensors, along with an error correction method. A multi-layer dynamic coordinate transformation model is developed to accurately map sensor data to the wheel′s 3D geometric information without being constrained by placement eccentricity. A stepwise calibration strategy is employed, using cube, cylinder, and profiled rotary calibration blocks to sequentially calibrate the installation pose and position parameters of the sensors. A pose fine-tuning mechanism is further implemented to achieve coplanar calibration of multiple sensors, overcoming coplanarity challenge caused by assembly errors in large-scale scanning systems. To address wheel placement eccentricity, an eccentricity error compensation method based on dynamic polar coordinate correction is introduced. By computing the axis offset in real-time and tracking the workpiece axis trajectory, radial dimension measurement errors are significantly reduced, overcoming the limitations of traditional mechanical centering under special operating conditions. Experimental results show that the system achieves an absolute measurement error is less than ±0.069 mm, a repeatability standard deviation below 0.049 mm, and a fluctuation range of radial dimension errors after correction reduced to within 0.170 mm, meeting industrial-grade precision measurement requirements. In practical engineering applications, the maximum relative error between the system′s measurement results for complex geometric features of a 915KKD-type wheel and reference values obtained by a laser tracker is less than 0.135%, confirming the system′s reliability and engineering applicability. Beyond train wheels, the system can be extended to other rotary workpieces for 3D precision measurements, providing a universal calibration and error correction solution for multi-line-laser-sensor rotational scanning measurement systems.