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A belt conveyor is a continuous conveying machine in which the conveyor belt serves both as the traction mechanism and the load-carrying mechanism, requiring high standards for the design of its components. The drive drum is the main driving component of a belt conveyor; it transmits the high torque generated by the conveyor’s main motor to the conveyor belt, thereby pulling the load and enabling transportation. Its reliability and service life have a significant impact on the performance of the conveyor. Currently, drive drums are mostly manufactured using welding methods, and their main components generally include the drum body, drum hub, and drum shaft. During the normal operation of a belt conveyor, the drive drum is subjected to circumferential shear forces as well as alternating radial tensile and compressive stresses; cracks in the welded areas can easily propagate, leading to fatigue failure and resulting in the failure of the drum. Therefore, the design of the welding position for the drive drum is particularly important. 1. Force analysis of the drive drum: In addition to gravity and torque, the drive drum is also subjected to the tension of the conveyor belt. For the purpose of checking the drum strength, it is assumed here that the drum is operating at full load, meaning that there is no static arc in the tension of the conveyor belt on the drum, and the sliding arc covers the entire wrap angle. The tension of the conveyor belt on the drum cylinder is shown in Figure 1. Within the wrap angle α range, the following formula holds according to Euler’s formula for elastomers: Fθ = F2e^μθ, where F2 is the tension of the conveyor belt at its loose state, in N ； μ —— Friction coefficient between the conveyor belt and the drum ； θ —— radians measured from point b, rad ； Fθ —— the tension exerted on the conveyor belt at position θ, in N. The normal pressure Pθ acting on each unit area of the drive drum at θ, and the friction force fθ acting on each unit area are given by: Pθ = 2Fθ/BD = 2F2eμθ/BD; fθ = μPθ = 2F2eμθ/BD. Here, B represents the width of the conveyor belt, in meters ； D — outer diameter of the drum, m. 1. Finite element model of the drive drum (1) Geometric parameters of the drive drum: Since it is complex to establish a three-dimensional finite element model of the drive drum, corresponding simplifications must be applied. For example, small radii, chamfers, and shaft journals can be ignored, and the constraints imposed by the bearing seats on the drum can be treated as those of a simply supported beam. The simplified structure of the drive drum is shown in Figure 2. a – distance between expansion sleeves ； b – Cylinder length ； c - bearing spacing ； Total length of axis d ； e-axis end length ； f – Hub width ； g – width of the expansion sleeve ； h outer diameter at one end of the shaft ； Inner diameter of the expansion sleeve i ； j – outer diameter of the cylinder ； k – Simplified wall thickness; (2) Material properties of the drive drum: The drive drum is primarily composed of a cylinder body, a hub, and a drum shaft. The material used for the cylinder body is Q345B, with a yield strength of 345 MPa ； The hub material is ZG230—450, with a yield strength of 230 MPa and a tensile strength of 450 MPa ； The drum shaft is made of 37SiMn2MoV material, with a yield strength of 835 MPa and a tensile strength of 980 MPa. Using an elastic modulus of E=210000 MPa and a Poisson’s ratio of μ=0.3, material properties were assigned to the cylinder body, cylinder hub, and drum shaft respectively. (3) The meshing of the drive drum is handled in the drive drum meshing module; the global seed count is set to 15, and high-precision quadratic reduced integration C3D20R element types are used, which effectively prevents the hourglass problem. The complex stress distribution and deformation mechanism of the drive drum are the main reasons that make drum design difficult. The ABAQUS software was used to conduct three-dimensional finite element static analysis of the drive drum of a belt conveyor under normal operating conditions and reverse rotation conditions, thereby determining the pattern of alternating stress distribution on the drum. The results of the finite element calculations can be utilized to identify the weak points in the design. Research shows that it is reasonable to control the welding position where the drum hub is connected to the drum body at 12%~17% of the total length, providing a basis for drum design.