Optimization of conveyor belt manufacturing processes, minimizes incubation interval of rubber mixture whilst optimizing thermal management throughout

• Main Author: MASBERG, ULLRICH
• Format: Patent
• Language: English; German
• Published: 02.08.2007
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; PERFORMING OPERATIONS; PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCESIN A PLASTIC STATE; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

The incubation interval of the rubber mixture is intentionally reduced to zero, or virtually zero, before raw belt material manufacture or before commencing molding. The initial rubber mass temperature at the initiation of vulcanization reaches 50% or more of the heating plate wall temperature. The incubation potential is reduced to a set value exceeding zero before initiation of vulcanization. The initial temperature of the mass on average, is greater than or equal to 50% of the tool wall temperature. To set an incubation potential, a temperature profile is imposed along the production line. Selected, controlled tempering at each process zone, assures the desired incubation potential and controlled initial temperature for the vulcanization process in the pressing zone. The temperature profile at the wall of the pressing tool approaches the tool temperature, e.g. 180[deg]C or other values. The incubation potential provided, is measured in terms of cross linking behavior after making the mix and before manufacturing of the raw molding, from vulcameter measurements, or similar suitable methods. A process control system is employed for conversion and monitoring. Processing employs calendering to reduce incubation potential to a set value. If an extrusion process is used, this is used for the same purpose. Before vulcanization, the raw material enters a heating zone where infra red-, induction-, turbulent flow heating or contact heating, results in an average initial temperature above room temperature, generally reaching 50% or more of the heating plate temperature. Vulcanization is interrupted at less than 100% completion, the relevant belt section being removed from the mold. The degree of vulcanization at this stage is always the same, through use of a process optimization system. Controlled cooling takes place in the holding zone, where internal heat within the conveyor belt section is used for after-vulcanization. Die Erfindung betrifft ein Verfahren zur Erzielung minimaler Vulkanisationszeiten bei der Verarbeitung von vernetzenden Polymeren der Klassen Elastomere in Verbindung mit unterschiedlichsten Festigkeitsträgern (Stahlseile, Drahtgewebe, technische Textilgewebe u.a.) zu Fördergurten für den Transport von Schüttgütern, mittels Prozesse wie Kalandrieren oder Extrudieren und Pressen, um nur beispielhaft die wichtigsten Teilprozesse des gesamten Herstellungsablaufes zu nennen. Es ist Aufgabe der Erfindung, die wirtschaftlichste Vulkanisationszeit zur Fördergurtherstellung anzunähern bzw. zu erreichen und zusätzlich das Qualitätsprofil konstant zu halten.