The conveyance of coal slurry is a critical step in the coal washing and beneficiation process. As a core component of the conveyance system, erosion and wear in elbows directly affect equipment service life and operational efficiency and also increase maintenance costs. To clarify the influence of key variables on the erosion behavior of elbows, this study employs a CFD-DEM coupled method and incorporates three erosion models to investigate the mechanisms of erosion wear under five key variables: conveyance velocity (1.5-6.0 m/s), particle density (1600-2600 kg/m³), particle size (50-650 μm), pipe inner diameter (200-460 mm), and bend angle (30°-90°). The study also compared and analyzed the predictive reliability of the different models. The results indicate that the E/CRC model demonstrates the best balance and reliability in predicting slurry erosion, with a maximum predicted erosion rate of 8.74×10?? kg/(m²·s). Among these factors, transport velocity had the most significant impact on erosion wear, with the erosion rate exhibiting an exponential increase with flow velocity; particle density was positively correlated with erosion intensity; when particle density was 2600 kg/m³, the maximum erosion rate increased by approximately 209% compared to 1600 kg/m³; the influence of particle size exhibited nonlinear characteristics, reaching a peak erosion rate near 650μm; once the bend angle exceeds 60°, the erosion rate rises sharply; the erosion rate in a 90° elbow is approximately five times that in a 30° elbow; as the shape of the coal slurry particles evolves from spherical to rod-like, the erosion effect intensifies; conversely, the influence of the pipe’s inner diameter on erosion wear in elbows is relatively minor. These findings hold significant theoretical importance and engineering application value for reducing operational and maintenance costs at coal preparation plants and enhancing production safety and stability.