Conti Machinery Focusing on Output Flexibility

Many tyre manufacturers are currently grappling with reduced demand. For this reason, reports Karsten Jung, CM Conti Machinery’s head of Sales and Service, at present an increased focus is being placed upon tyre building equipment that can deliver smaller load sizes. “Many customer budgets are frozen so smaller load sizes are attractive,” Jung comments. “Our answer to the current situation is flexibility and lower output.” For passenger car tyre segment customers, Conti Machinery – a proponent of two-stage technology – offers output flexibility through a combination of its KM F and PU 15 SB tyre building machines.

The KM F takes care of the first stage of tyre building, manufacturing the carcass. Once this stage and the transfer of the carcass has been completed, the process of building the green tyre starts in the second stage – and this is where the PU 15 SB takes over. The PU 15 SB is used for assembling the belt package consisting of two steel cord belts, the jointless cap ply and the tread, and combining it with the carcass, thereby producing the green tyre. The principle of the PU 15 SB is based on separating and paralleling the work operations of assembling the belt package and building the tyre. This results, says Conti, in high machine productivity combined with very short cycle times, as well as a high level of tyre quality.

Operation of the PU 15 SB involves the carcass loader positioning the carcass on the shaping head, where centring and preshaping operations take place. At the same time the belt transfer ring takes the belt assembly from belt drum 1 and positions it centrally and symmetrically in the middle above the carcass. The carcass is then expanded into the belt assembly. After the stitching procedure, the belt transfer ring carries the tyre to the take-off point. Parallel to this, two processes take place at the belt machine: The first and second belt plies are assembled via partial automatic control on belt drum one. The jointless cap ply is then automatically placed on belt drum 2, which already holds the steel belts. The belt machine then swivels through 180°. The precut tread is applied and manually spliced. At the same time a new winding process begins at belt drum 2 and the next carcass is placed on the shaping machine. According to Conti, this splitting of the work operations among three stations leads to short cycle times when manufacturing jointless cap ply tyres. A new carcass is added and a new tyre built in each work cycle.