Abstract: The paper investigates engagement contact forces of flight chain and chain wheel based on the characteristic of structure and drive of short-distance heavy duty scraper conveyor. The formulation of rotation angle, engagement force, and chain tensile force is established according to force equilibrium conditions of engaged chains of flight chain, which omits the influence of eccentricity, suspension tensile force, elastic distortion, design and manufacturing errors. Comparison of analysis results with above formulation between 9°,12°,15° pressure angle of 10 teeth chain wheel and 8 teeth, 10 teeth, 13 teeth with 12°pressure angle indicate that wheels have less pressure angle and teeth will gain larger tangential force and engagement force of single teeth, while demand higher material strength of chains and wheels. At last, simulation results of finite element method is carried out to verify the formulation results.