by Thomas Foschini24   Novembre   2014

The 'Press System' for ceramics

The shaping of support obtained by pressing atomised powder is one of the most important phases of the ceramic productive cycle. SITI B&T company of Formigine (Modena, Italy) takes the challenge with the creation of EVO 3.0, a range of new generation high tonnage presses – up to 40 thousand tonnes – envisaged to meet high productivity, flexibility, energy saving and waste reduction according to market needs.
As Maurizio Barbanti from SITI B&T Group press designing team underlines, “What has been completely redesigned is not the single machine itself as the entire production process, with patented technology, easily able to fit any type of EVO press”. What the Formigine-based company offers, with a 5 year guarantee on its presses, is a new technological solution for each phase of the pressing procedure so as to enhance final results.

Let’s start with E-Synchro®, the new electromechanic device for mould release, made of an integrated encoder brushless engine and a “heavy duty” ballscrew so as to guarantee utmost accuracy and efficiency in the transmission of motion. “With this technology– Barbanti explains – the maximum position error is lower than 0.05 mm. Synchronised ejection is not obtained electromechanically nor hydraulically: the position of the four ejectors is electronically controlled, and each of them can be individually moved, positioned, and set to the desired speed, acceleration, ramps and functioning”. Two are the major benefits: stability and repeatability of the process – environmental circumstances do not affect the behaviour of the ejecting mechanism – and reduced maintenance as there is no piping involved (proportional valves, high-pressure pipes, etc.).

Fasty is another press-integrated patented technology “easily fitting EVO presses for a quick change of the mould” Barbanti goes on. It is fitted with loading and unloading devices and does not need any “side mechanism”. Fasty is an AGV machine with two movable side shoulders on rolling guides and an integrated pusher head. “Since loading and unloading are carried out independently with Fasty, the setting of the mould is the only thing being made traditionally, by means of a lift truck, thus increasing automation and reducing the possibility of human error”. Speaking of numbers, changing a mould with Fasty takes less than 30 minutes, managing moulds up to 2450x1500 mm weighing up to 10 tonnes.

But the greatest and probably most significant innovation in terms of  reduction of consumption and production efficiency proposed by Siti to the entire press cycle is the Start&Stop technology: basically the concept is “turn the engine off” when not needed during production process. The solution is an inverter controlled motor hydraulic generator replacing previous inertial flywheel technology (which already allowed 50% average energy saving compared to traditional multiplying technology). The group is made of a high speed asynchronous motor paired with a fixed displacement piston hydraulic pump. Each hydraulic generator can pump a maximum pressure of 420 bar. “Thanks to Start & Stop – Barbanti observes – the total necessary power for pressing can be fractioned, having different hydraulic generators at one time: in case of maintenance it won’t be necessary to halt the whole press, it will just be necessary to isolate the single group in need for assistance”. Last benefit concerns spare parts inventory reduction, made possible by the fact that installed presses are  fuelled, independently of their tonnage, by the same Start&Stop”.

Interface for monitoring all process parameters and integrated system for quality control give the last touch, stepping ahead of previous technologies in terms of usage and efficiency. The quality control system for EVO 3.0 presses is Genius Box® and allows a real time monitoring of dimensional parameters – including thickness – of apparent density and of possible faults on tiles’sides, instantly sending all information to the machine and automatically activating the right correction. The press monitoring system, installed on all machines, enables the keeper to make a complete check up of the equipment, enabling statistics on production data and the possibility to ask for telecare and online support when needed (an optional extra which can be installed upon request).


Last, a product specifically designed for large slabs and panels: Supera®, the press presented at Tecnargilla, which will be on the market from 2015. Its innovations are the complete lack of mould, and patented solutions for the reduction and elimination of processing swarf and waste. The results: a high flexibility in shapes and layers – thanks to the fact that there is no mould and tiles can be cut in different sizes both raw and cooked; the absence of foundations; solutions to guarantee a better flatness. All of this enables to make tiles of any size and sheets of various layers and thickness, while limiting energy costs.