The melting process is responsible for up to 85 percent of the energy consumption in the manufacturing process, depending on the type of glass and the production method. The machine builder Waltec is an example of how it also pays to look for potential savings in the remaining 15 percent. This medium-sized enterprise based in Bavaria, Germany, specializes in sustainable process optimizations at the hot end with a focus on fully automated carousel-type machines for pressing tableware. Each machine contains up to four press cylinders, each of which is supplied by its own plunger with a customized volume of gas.

Objective: sustainable solutions at the hot end for glass manufacturers like Trend Glass.

For decades, all developments in the glass presses at Waltec have literally been “powered by Siemens.” In other words, Siemens has always replaced all the carousel-type press lines’ automation and drive technology with new technologies and concepts.
For example, in the case of the servo-hydraulic machines, the Sinamics S120 modular inverter system and Simotics servomotor were retrofitted to drive the pumps. Until that time, pressure and volume flow in the hydraulic system were controlled by valves. Process control for the presses continued to be performed by a Simatic S7-300 in conjunction with a Simatic HMI device.    When the switch was recently made to fully electric e-servo presses, it quickly became apparent that the typical Siemens drive technology environment would remain the same. Programming is now even easier, because hydraulics are no longer involved.
Waltec is seeking to migrate to Simatic S7-1500 controllers. This will involve the introduction of the TIA Portal, which will provide Waltec with full access to all of the digitalized automation, from digital planning and integrated engineering to transparent operation.

Based in Poland, Trend Glass describes itself as a global market leader in the manufacture and sale of consumer, decorative, and tableware glass – including bowls, vases, and drink containers.
Trend Glass will be gradually retrofitting its glass presses. The company chose the fully electric version of Waltec for two of its new acquisitions, because Trend Glass has already been following a sustainability strategy for many years. The melting process also accounts for the highest energy requirements at the company, but the press area is the immediate second.