"Greater Efficiency" – How Siemens can support tyre industry vulcanisation

Vulcanisation is known to be bottleneck in tyre production that can significantly influence a factory’s output. Siemens specialises in the field of automation and as such it aims to provide the tyre industry with “greater efficiency” in this particular area. The company displayed its product range at February’s Tire Technology Expo in Cologne, Germany, and Tyres & Accessories spoke with Stefan Morgenstern, senior business development manager for the company’s Industry Automation division, about the ways Siemens can enhance efficiency in the tyre manufacturing process.

While vulcanisation process cycle times are substantially affected by parameters such as tyre size or the compounds used, Siemens is unable to influence these factors. And Morgenstern also sees limited potential for optimising the vulcanisation process at the stage of loading and unloading the tyre from the vulcanisation press. “Loading and unloading accounts for only a small portion of the total curing process and is a mechanically challenging task,” he explains. “We could only achieve a very limited speeding up of the mechanical components with the help of electronics.” Despite this, he is confident that Siemens solutions can be used to minimise downtime while simultaneously reducing costs.

“Improved diagnosis helps to identify and rectify errors as quickly as possible. In this way productivity can be maintained at a maximum,” says Morgenstern, explaining how efficiency can be raised in the vulcanisation process. “Another approach is cost reduction in order to enable tyre makers to invest in further machinery.” Automation components make up about ten per cent of a mould cure press’s total price. And even though the unit’s mechanics account for the remaining 90 per cent it must be asked, for example, whether a single press with four press arms, an increasingly-adopted configuration, really needs a HMI (Human Machine Interface) or their own SQL database for recipe management. 

“We have already proposed an optimised HMI concept – for example with our wireless mobile panel – to our customers. This entails a row of machines sharing a mobile HMI unit that can be deployed on every machine if required. This even works with the emergency stop function,” comments Morgenstern in reference to equipment safety. On this point, Siemens views the safety of personnel and equipment as the highest priority, above increasing efficiency or reducing costs. Therefore the automation specialist has a “safety concept” for its vulcanisation presses that provides for the swapping of standard parts for “safety” components. As part of this, in addition to mandatory items such as emergency stop buttons, Siemens offers features such as light curtains or radar scanners in order to further improve safety. “Our networks can simultaneously handle safety and standard protocols,” shares Morgenstern. As a result, the overall automation structure becomes more transparent, lean and – last but not least – cost efficient.

The integration of both “under the same roof,” as it were, in turn makes savings possible as doing so avoids the higher costs that would be incurred by having non-standard control systems and fuses in two separate systems. All this relates to the scalability of vulcanisation press-related automation solutions. According to the senior business development manager for Siemens’ Industry Automation division, there is a wide range of variation in the machinery available on the market and the cost for a fully-equipped, high performance control system can cost up to ten times more than a basic control system with an I/O interface. “Not every press requires a PLC (programmable logic controller) to operate. Here we have the Eastern European and Asian markets in mind, where more than half of all tyres in the world are produced,” Morgenstern explains. 

While, as the company explains, the Siemens software package for tyre vulcanisation presses is based on a modular open source code, options beyond the usual functionalities can be integrated according to customer/manufacturer wishes. Therefore, Morgenstern says that “a broad portfolio of conventional and PC-based control” that are all “engineered with the same TIA (totally integrated automation) portal software” can be offered. This is a further benefit in terms of efficiency for the company, in addition to the application of synergies in relation to the software and hardware modules used by various machines.

Incidentally, Morgenstern also views the Siemens system’s ability to perform energy measurements and correlate these with the vulcanisation presses’ control process as a further advantage. “Using this, the tyre maker can analyse and optimally allocate its energy consumption. The goal is to avoid the horrendous surcharges incurred during peak load periods. This is an issue faced in many countries.” He shares that in some less developed economies an overload during peak periods can sometimes lead to complete blackouts and unwanted, costly idling of machinery. Consequently, this Siemens system function contributes to greater efficiency during the vulcanisation process. 

All these arguments will be harder to avoid in future, as Morgenstern points out that competition between tyre manufacturers is “great” and the established names are increasingly sharing the market with suppliers from Asia. “The pressure on prices is already being felt,” he says. Of course, rising demand for tyres in emerging markets will lead to an increase in global production capacities. Therefore it is not surprising that Morgenstern also notes the current positive trend in demand for vulcanisation presses. “Some OEMs are operating at the limit of their capacity. What’s more, a regional shift has been observed, and tyres are increasingly being produced in Asia, Eastern Europe and Latin America. Alongside major greenfield projects we are also constantly seeing ‘retrofits’ as part of this production shift,“ he explains.

A retrofit involves an upgrade of the control technology employed on older vulcanisation presses, giving them the benefit of modern Siemens technology. “The boost in technology to a new-generation PLC is very high. The advantages are particularly felt in terms of safety, diagnosing problems and troubleshooting times,” Morgenstern shares. Admittedly, it doesn’t always make sense to undertake such an investment, and sometimes investing in a new press is the preferred solution. “The decision must be made on a case-by-case basis,” the Siemens manager comments, noting that the decision depends on numerous factors. “The type of mechanism employed and its condition determine productivity and tyre quality. Should this fall within the desired scope, renewing the automation will cost only around ten per cent of investing in a new product. And it will bring about a reduction in down time plus save on the cost of replacement parts. Our experts have retrofitted presses for many years now,” says Morgenstern, emphasising that Siemens can also improve vulcanisation efficiency for “old” tyre factories.