{"id":15086,"date":"2022-03-02T14:17:18","date_gmt":"2022-03-02T19:17:18","guid":{"rendered":"https:\/\/blog.wika.com\/us\/\/?p=15086"},"modified":"2024-02-27T13:58:58","modified_gmt":"2024-02-27T18:58:58","slug":"heavy-duty-pressure-transmitter-tire-curing","status":"publish","type":"post","link":"https:\/\/blog.wika.com\/us\/applications\/heavy-duty-pressure-transmitter-tire-curing\/","title":{"rendered":"Heavy-Duty Pressure Transmitter for Tire Curing"},"content":{"rendered":"

Tired of high maintenance costs due to measuring instrumentation failure during the curing process, a major tire manufacturer switched to WIKA\u2019s S-20 heavy-duty industrial pressure transmitter for reliable performance and a significantly\u00a0longer service life. <\/p>\n

<\/strong>Automotive technology continues to evolve, with alternative fuels, advanced electronics, digital connectivity, and more. But one aspect remains fairly unchanged: the tires. The vast majority of today\u2019s tires, no matter how basic or high performance they are, undergo vulcanization, or curing, to make them roadworthy.<\/p>\n\n

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Tire production (click image to enlarge)<\/p><\/div>\n \n

Making and Curing Tires<\/h2>\n

Manufacturing the different components of a modern tire involves compounding, mixing, and kneading up to thirty raw materials: natural and synthetic rubbers, sulfur, steel, carbon black, fibers, and other additives. Once all the parts \u2013 belts, sidewalls, fillers, beads, etc. \u2013 are produced and built up, this \u201cgreen tire\u201d is put into a curing, or vulcanization, press.<\/p>\n

The tire curing press is a round mold with a bladder in the center. Hot water or steam is pumped into this bladder, which expands and presses the raw tire against the sides of the hot mold. Under high pressure and temperature, the rubber compound vulcanizes into flexible, elastic rubber. The mold also gives the tire its final shape and sidewall markings.<\/p>\n

The Role of Pressure and Temperature in a Tire Curing Press<\/h2>\n

Tire curing takes time, energy, and high pressure and temperature. Having the right pressure and temperature during the vulcanization process directly impacts the quality of the final product and the efficiency of the entire process.<\/p>\n

Pressure measurement during vulcanization<\/h3>\n

The curing press\u2019s bladder is under high pressure, up to 350 psi (24 bar), so that it can push the green tire against the mold\u2019s walls. If the pressure is too low, the polymers will crosslink less, resulting in a less-rigid tire and, therefore, tires with lower mileage. Pressure that is too high results in unnecessary energy consumption at the plant and reduces the bladders lifespan, resulting in high maintenance costs and downtime.<\/p>\n

Temperature measurement during vulcanization<\/h3>\n

Temperature affects the curing speed. The hotter the press, in the 340\u00b0F to 390\u00b0F (170\u00b0C to 200\u00b0C) range, the shorter the process and the sooner the next green tire can be processed. But if the temperature is too high, the rubber is damaged.<\/p>\n

Problem: Failing Pressure Transmitters During Curing<\/h2>\n

A major tire manufacturer was having significant issues with the pressure transmitters in its curing presses. Namely, the sensors kept failing, leading to frequent downtime and extra costs. Not having success dealing with the original supplier, engineers at the tire company reached out to WIKA to help them figure out what was going on.<\/p>\n

After looking at the manufacturer\u2019s curing presses and the failed pressure transmitters, WIKA specialists discovered that there was nothing wrong with the equipment or the process. Their current sensors, however, were not robust enough to withstand the press\u2019s challenging process conditions:<\/p>\n