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The drums in a roller conveyor are cylindrical components, divided into drive rollers and idler rollers. It is widely used in applications such as rotary screen printers, digital printers, conveyors, and paper manufacturing. The drums in roller conveyors are usually made of seamless steel tubes; however, depending on the requirements of different manufacturing processes, materials such as aluminum alloy 6061T5, 304L/316 stainless steel, 2205 duplex stainless steel, cast steel, and solid forged alloy steel cores may also be used. After drum forming, surface treatment or coating processes such as painting, galvanizing, TEFLON spraying, rubber coating, chrome plating, ceramic spraying, and oxidation are required to prevent rust and corrosion, enhance wear resistance, and provide support. Classified by size, there are large ones such as rollers used in papermaking machinery (with a length of over 10 meters). Those with a diameter of over 1500 mm), and there are also smaller ones such as flat idler rollers used on conveyor belts on automated assembly lines (usually with a length of less than 1 meter), with a diameter of 159 MM. Drum diameter options: 25mm, 32mm, 38mm, 42mm, 50mm, 57mm, 60mm, 76mm, 80mm, 89mm. The principle behind determining the drum diameter is that when the tensile stress on the belt in a circular configuration is high, the additional bending stress should be lower ； Conversely, when the tensile stress is low, a slightly higher bending stress is allowed, allowing for the use of a smaller drum diameter. Materials for rollers: galvanized carbon steel, chrome-plated carbon steel, rubber-coated carbon steel, aluminum alloy, stainless steel, ABS, etc. Roller type selection: unpowered rollers, single-chain rollers, double-chain rollers, \"0\"-belt rollers, conical rollers, grooved rollers. Roller fixation methods: spring compression type, internal tooth shaft type, fully flat tenon type, and through-shaft pin hole type. The production of rollers involves a series of processes, including initial turning of the roller body, initial static balance adjustment, welding of the shaft end interference fit devices, precision turning, and precise dynamic balance adjustment. If the requirements for dimensional tolerances such as roundness, cylindricity, and straightness are below 0.2 MM, external cylindrical grinders or roller grinders are required for further grinding after turning. If surface hardness is required, an additional heat treatment step is necessary. When transporting materials, the roller conveyor can also adjust the height of its mechanical legs according to the requirements of the working surface, in order to work in conjunction with other mechanical equipment during production. The thickness of the drum shell depends on factors such as the diameter of the drum, the length of the drum barrel, the tension of the conveyor belt, and the wear during braking. Calculating the thickness of the drum shell is very difficult, and the values obtained through such calculations are generally on the low side. To ensure wear resistance and ease of manufacturing, the thickness of the drum shell is usually set to be relatively large. After determining the thickness of the drum shell, its strength is checked. Since the drum shell is subjected to normal and tangential loads, and the magnitude of these loads varies along the circumference of the drum, there is currently no accurate method for calculating the thickness of the drum shell. Although finite element analysis can provide relatively accurate results, the lack of specialized software for calculating belt conveyor drums means that finite element analysis can only be applied to individual drums. In the case of drums with soft radial plates, the maximum stress generally occurs in the middle part of the drum shell’s length and on the outer side of its thickness; under normal circumstances, this stress can be expressed using approximate values with sufficient accuracy.