Fast, efficient andsustainable: Fully electric injection molding machines

Welltec Machinery Ltd. is a technological leader in the manufacture of injection molding machines. Since few Chinese suppliers have mastered the industry’s most recent advance-ments, Welltec expanded its search and found an innovative and reliable partner in B&R. Together, the two companies now produce high-performance, fully electric injection molding machines with sophisticated technology that maximizes production efficiency and ensures premium product quality.

Fully electric injection molding machine from Welltec’s G-series. Phot

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Welltec’s machines range from 20 to 7,000 tons of clamping force. With an ongoing dedication to research and development, the company is regularly introducing innovative new products and system solutions to the market. One particular focus over the past several years has been the production of fully electric injec-tion molding machines.

Hydraulic vs. fully electricThe primary differences between electrical machines and their hydraulic counterparts are the more powerful electronic compo-nents and the use of electrical axes.

Fully electrical machines feature high-speed injection control that provides extremely efficient production. Highly precise servo positioning and perfect reproduction of process curves ensure outstanding product quality.

Manufacturers of plastic products also need cluster control and management systems to be integrated in the production line, while remote diagnostics and maintenance options are also frequently a decisive factor for their customers. With these challenging require-ments in mind, Welltec and B&R set about the task of successful-ly implementing them all in one state-of-the-art machine.

Fast reactions with POWERLINKFully electric injection molding machines require extremely fast motion control in order to maintain the constant cycle of pro-

cessing steps from plastification and injection to closing the mold, switching and opening the mold, and finally ejecting the finished product.

The demanding response times required throughout the entire production line can only be satisfied by a powerful and precise communication system between the controller and drives. Its im-pressive clock synchronization accuracy (< 0.1 µs) and extremely fast network cycle times make POWERLINK the ideal solution for the plastics industry.

Perfect combination of speed and precisionThe electric machines are equipped with a servo regulated power pack that reduces mechanical wear when opening and closing the mold. Welltec’s G-series devices feature a unique function for repeated infinitely adjustable closed-loop force control and mold closing in a single injection molding process. This reduces the time and cost of maintenance involved in exchanging and lubri-cating the high-performance ball screw.

The system, which consists of Power Panel and ACOPOSmulti de-vices, delivers the excellent stability and precision required for the injection molding process. The G-series of fully electric injec-tion molding machines achieve a positioning precision of 0.01 mm and pressure control deviation of only 0.1 percent. The ACOPOS-multi drive system meets all the control requirements for the various production stages. The injection velocity is 20 percent

Vollelektrische Spritzgießmaschine der Serie G von Welltec

“The cooperation between B&R and Welltec has created significant added value for bothus and our customers. We have made a great leap forward and strengthened our technologicaland competitive edge.”

“We will be expanding our relationship with B&R in the future in order to offer our customers even better products.”

Guoqiang CaiChief Engineer at Welltec

Welltec uses the Automation Studio 4 platform to develop its modular software. This allows multiple software engineers to each work on a different autonomous module simultaneously and load them to the hardware separately. This not only shortens development times, but also makes it easier to develop modular machines with flexible configurations.

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higher than comparable products, which gives the customer greater flexibility as well as higher quality.

Process modeling for adaptabilityThe injection molding machine must not only be flexible enough to produce a range of different products, it must also be simple enough to allow operators to learn it quickly and use it reliably. With B&R’s process modeling, the user only has to enter basic parameters such as product specifications and the type of raw material. The rest is handled automatically by the process model.

“B&R’s engineers provided fantastic support with the process modeling. The result of this collaboration is machine software that can be adapted effortlessly to different machine configura-tions and different production processes,” explains Guoqiang Cai, chief engineer at Welltec.

iSeeWelltec has developed its iSee mobile apps for end devices like smartphones and tablet PCs to provide remote access to injec-tion molding machines in different plants. iSee cluster manage-ment allows the customer to access and analyze current and historical production data, order processing data, the operating status of various systems and much more – at any time. The con-nection to the controller is made via the open Ethernet interface on the B&R Power Panel.

Integrated condition monitoring“We are always working towards more and more intelligent ma-chines, so it made sense to add B&R’s condition monitoring solution to our development plan. We are convinced that this feature will become increasingly important to our customers in the future. Monitoring conditions such as vibration, temperature, power supply and more provides advanced warning of potential problems. This lowers maintenance costs and improves opera-tional safety,” says Cai.

The production facility for G-series fully electric injection molding machines.

The ACOPOSmulti servo drive system used by Welltec. Phot

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