Injecting flexibility into machine design

The requirements LWB laid out for its new generation of rubber injection presses were both demanding and innovative: smartphone-like operation, rapid software development and easy management of machine variants. With B&R's mapp Technology, the company has achieved these goals successfully and sustainably.

No car can do without them – there are hundreds in every vehicle. They cushion, insulate, filter, divide, connect and seal: molded parts made of rubber and thermoplastic elastomers. And it's not just cars that rely on them, but nearly any machine you can think of – from washing machines to crude oil pump stations. With new compounds being developed all the time and parts becoming increasingly intricate, these materials and their potential uses are growing more widespread and diversified.

"The more varied the range of applications, the more specialized the requirements that these elastic components place on production systems," says Peter Radosai, LWB's head of sales for the European market. "We've created a broad palette of standard and specialty solutions for injection systems, clamping units and entire injection molding machines that allows us to accommodate any set of requirements."

In the 50 years since the first LWB injection press was completed, the company's original portfolio of horizontal and vertical variants for rubber has expanded to include systems for producing molded parts from thermoplastic elastomers as well. To meet the diverse needs of its primary market – automotive suppliers all around the world – LWB machines need to cover the full spectrum from low-cost to high-end solutions. For more than a decade, the company got by with only two controller variants, both based on proven B&R technology.

"Despite making continual improvements to the controller over four generations, the time had come to take a more daring leap in innovation," explains Radosai. One particular innovation that LWB had in mind was to model the new design after modern smartphones in terms of operation and usability – which would be revolutionary in the field of rubber injection molding.

"We're seeing more and more users wanting to navigate by swiping and pinching – like they do on their smartphones," reports Radosai. "At the same time, there are heightened expectations for faster response times, new control algorithms, more extensive process monitoring and data acquisition, more in-depth diagnostics and help systems, and integrated energy management."

Following an intensive and impartial evaluation of the market, B&R emerged victorious over a well-known supplier of application-specific control solutions. "It was the total package that convinced us," recalls Radosai.

A key part of that total package: mapp View. Based entirely on web standards like HTML5, CSS and JavaScript, B&R's new HMI solution gives developers all the benefits of web connectivity right in the automation software – without requiring any training in the underlying technology.

Another benefit of B&R's HMI solution is the fact that – with content and layout handled separately – design changes can be implemented with minimal effort and easily transferred to other machines. mapp View also offers maximum flexibility in terms of HMI hardware. Any device that can run a web browser can be used as a display terminal. What's more, it was easy for LWB to integrate web-based user interfaces for third-party components directly into its own HMI application. "When rubber parts leave the mold, they have a temperature of 160°C and are slow to cool," explains Radosai, "so it is particularly important that the terminal is easy to use even with gloves on."

LWB selected an HD TFT multi-touch display unit with an 18.5" diagonal, in combination with a Panel PC 2100, which is suitable for either swing arm or control cabinet mounting. The modular Panel PC allowed LWB to achieve another of its core objectives. All LWB injection presses – even those for the most cost-sensitive markets – now use the same control hardware.

In terms of software architecture, the changes were even more fundamental. With B&R's mapp Technology, LWB has only a single software project to manage. "Before, 10 machines meant 10 different software projects. With different hardware configurations and custom adaptations, we'd have to get into the code and make changes every time," says LWB process engineer Markus Zabel, the main author of the requirement specifications for the new controller.

With B&R's mapp Technology, all the standard modules available for an LWB injection press are managed in a single project. During commissioning, the technician simply opens configuration screen in the HMI application and enables whichever modules are actually being used. Without writing a single line of code, the necessary software can then be generated at the push of a button.

"Many of our customers choose to add modules to their machine later on. Now, adapting the software to these expansions is child's play. You just open the configuration page, enable the newly added module with a click, restart the controller and you're done," praises Zabel. "And now it's also just as easy to synchronize the software versions of machines that have accumulated over time, or to perform software updates."

The adaptability of the control software isn't limited to machine modules designed in advance, however. mapp CodeBox makes it possible to integrate future options, customer-specific machine modules, custom safety technology or handling systems without having to modify the machine's main project. This HTML5 application allows LWB to offer custom tailored solutions without the software overhead this would normally entail. As always, users don't need any training in web technology. All programming is done in the HMI development environment using Ladder Diagram (LD) or Structured Text (ST).

LWB was even able to bring added flexibility to the injection process itself using mapp Technology. An integrated mapp component makes it possible to integrate user-defined sequence controls into the control software. At any time, directly on the HMI panel, users can adapt the process to the specific requirements of the compound being injected or the part being molded. The sequence is defined via the graphical interface, and the PLC program is automatically updated in the background.

As impressive as the extensive functionality and countless innovations is perhaps the fact that LWB was nevertheless able to meet its ambitious deadline. The LWB process engineer has no doubt what was responsible for this success. "Thanks to mapp Technology, we were able to stay on schedule and have the new controller ready for series production in time for K 2016. To do that with a conventional approach would have required significantly more personnel and financial resources."

Some of the biggest reductions in development time came from one particular mapp component B&R developed specially for the plastics industry. It encapsulates all the standard elements of an injection molding machine, including the injection unit with its worm drive and the clamping unit with its hydraulic cylinders. The developer only has to define the necessary motion profile, and can concentrate more time on implementing the unique processes that differentiate the machine from the competition.

"The fantastic thing about it is that we're able simulate the entire machine, even before it physically exists," explains Radosai. "Not only does that mean fewer errors when we switch over to the real machine, it also allows us to show the customer what their machine will be capable of during the decision-making phase."

The real highlight of mapp Technology is that – in addition to the countless proven functional components – B&R also provides a standardized infrastructure for linking and diagnosing those components, as well as alarm handling, recipe management and energy management. When you add a new mapp component to your project, mapp AlarmX, for example, immediately begins handling its alarms. Thanks to the standardized interfaces between the modules, mapp components can also simply be copied from one controller to the next. The same applies to user-developed blocks, as long as they comply with the standardization requirements.

"For manufacturers of injection molding machines, mapp Technology offers a solution for creating modular, reusable machine software through simple configuration and minimal – if any – programming," concludes Radosai. "We're able to focus our attention and resources on the application itself."