Tire Manufacturing Equipment Information
Tire manufacturing equipment is designed for tire profiling and manufacturing. Tires are made using a variety of blending, extrusion, calendaring, cutting, assembly, and inspection equipment. The equipment is often tailored to individual manufacturing production needs.
Compounding is the bringing together of all the ingredients needed to mix a batch of rubber compound. Each component of a tire has a different application and may require a variation of ingredients to mix together to ensure the component can best perform its job. Mixing is the process of bringing all the ingredients together by applying mechanical work to blend them into a homogeneous substance. The mixing is done in three or four stages to incorporate the ingredients in the desired state.
Most parts of a tire are created using an extruder. Tire components such as tread, sidewall, and apex are prepared by forcing uncured rubber compound through an extruder to shape the tire tread or sidewall profiles. Extrusion is one of the most important operations in the tire manufacturing process because it processes the rubber compounds produced from the mixing operation and then prepares various components for the tire building operation. The extruder in a tire manufacturing process is a screw-type system, consisting primarily of an extruder barrel and extruder head.
Calenders are also a key machine in creating tires. Calendering involves the squeezing the compound into thin sheets using a calendering machine. Fabric Calendars and Steel Calendars produce thin sheets along with steel cords. Calenders utilize downstream equipment for shearing and slicing of calendered sheets. Calenders are used to produce the tire body plies and belts.
A tire is built by a robotized machine called a tire building machine (TBM). The TBM assembles all semi-manufactured goods such as: tread, sidewall, inner liner, body ply, bead, and cord body together to assemble green tires. At this point the tires are uncured and are referred to as green tires.
Video Credit: Jhon Jason
A tire is built on a flat drum in a two-stage process. In the first stage, the inner liner is wrapped around a drum and the first body ply is wrapped on top, followed by the second body ply. The bead assemblies are positioned and a bladder on the drum is inflated and pushed in from both ends of the drum, forcing the body plies to cover the bead assemblies. The sidewall sections then are then pressed onto both sides.
In the second stage of the tire building process, another machine is used to apply the belts, nylon cap, and tread material on top of the first stage. At this point, the tire still needs curing because there is no tread pattern.
Curing is the process of applying pressure and heat to a green tire in a mold in order to give it its final shape. After the mold closes pressure is inserted to make the green tire flow into the mold, taking on the tread pattern and sidewall lettering engraved into the mold. Once the tire is cured, the internal pressure is relieved and the mold is opened. The tire may then be placed on a PCI, or post-cure inflator that holds and inflates the tire until it fully cools.