Abstract : To achieve constant tension winding of tire inner liner rubber sheets, torque control is adopted, and the influence of radius adjustment is incorporated during the winding speed regulation process. Frequency conversion speed regulation is used to synchronize the winding speed with the traction speed. Based on this, a hardware system consisting of a computer, PLC, and frequency converter is constructed. The reasons for the non-constant winding tension are analyzed using the constant tension control principle, and improvement measures are proposed. Keywords : PLC; inner liner; winding; Siemens; frequency converter The tire inner liner production line of Qingdao Rubber Factory No. 2 was introduced from Italy in 1985. The production line consists of five main parts: extruder, calender, cooling device, guide device, and winding and cutting device. The production line still uses DC motors as the drive equipment, resulting in inaccurate tension control, a lack of automatic film thickness measurement system, and an inadequate monitoring system. The entire production line control system is not systematic. This study focuses on exploring the structure of the winding device control system and its modification methods. 1. Process Background and Hardware Structure The inner liner is located at the innermost layer of the tire. Its function is to reduce friction between the tire carcass and the inner tube, and to prevent air and moisture from penetrating into the tire carcass. For tubeless tires, the inner liner (i.e., the airtight layer) also plays a role in maintaining the internal pressure of the tire cavity. The inner liner requires both good airtightness and good adhesion to the tire carcass ply layers. In the inner liner control system, PLC-controlled winding has advantages such as low failure rate, high reliability, and convenient maintenance. The control of the winding device directly affects the thickness of the inner liner film. The key to its control is to achieve linear speed matching between winding, traction, and conveyor belt. The traction speed affects the speed of the plastic pad, and the winding radius gradually increases. The specific structure of the winding device is shown in Figure 1. [b][align=center]For more details, please click: Research on Control System of Tire Inner Liner Film Winding Device[/align][/b]