Following the waves of industrial innovation over recent years, as part of a fundamental drive to maximise productivity, one of the leading paper manufacturers has deployed industrial robots for label application to its finished products, the company’s Flintshire-based paper mill faced some serious problems with one of the robots functioning on site.

According to the lines automation engineer “Over the last couple of years our label applicator robot has becoming increasingly unreliable, resulting in a number of breakdowns which we cannot accept”. He added, “If we experience an 8 hour downtime event, it can lead to the mill stopping production”. The deteriorating reliability of the robot was clearly critical and warranted the purchase of a new robot.

The paper makers’ engineers thus presented their user requirement specification for a new robot to a few robotics companies. They explained that KUKA Robots, the German producer of industrial robots, most closely matched their brief in terms of capabilities and cost. Mark Fisher, project engineer at KUKA Robotics, commented: “Being cost competitive was an obvious key factor in winning the contract, but we also offered better overall value for the customer together with excellent customer support throughout the project”. KUKA Robots employed a 3G router solution and made sure that remote robot diagnostics are possible via LogMeIn (a remote control desktop website). According to Mark Fisher, the most challenging part of the project was calculating the arc the robot had to take relative to the roll diameter and width sent over the bus by the PLC.

To partner, Optima Control Solutions Ltd, an expert independent automation company, was approached by KUKA Robots and charged with the task of programming, installing and commissioning the new robot. Optima had to integrate the new robot with the existing machine control system. The mill’s automation engineer told us: “We had complete confidence in the company’s expertise – KUKA recommended Optima as the best system integrator out there. Their joint offering was within our budget and with their excellent reputation we had no doubts that they would do a great job.”

Stephen Carradice, Optima’s system design engineer explained that his main tasks were to engineer and commission the robot control software and to arrange integration between the existing Siemens S7 PLC and the new robot controls using a ProfiBus communications interface. The mill engineer commented: “Stephen’s technical competence was extremely good he was very thorough. Steve had only 12 hours to complete the complex installation and he managed to complete the job very successfully within that very limited time frame.”

When asked to summarise the overall benefits resulting from this project, the automation engineer told us: “Improved reliability was the main aim for us; the robot is now functioning 100% of the time so we can claim the whole project to be a success. It is critically important for us to maximise our machine uptimes and KUKA’s solution is fully delivering on its promise. A number of other automation projects are planned and we are looking forward to working with Optima and KUKA Robots again.”

Bridon International Ltd. is a world-leading manufacturer supplying specialist metal rope and wire solutions for a number of heavy industries. Their products are widely used in demanding environments such as oil and gas installations, mining and structural projects. With such diverse, complex and safety critical applications, Bridon’s products must meet the highest quality standards.

Bridon’s Doncaster plant in the UK manufactures a very wide range of wire products in order to meet the full spectrum of customer requirements. They, therefore, need flexibility from their production plant.

Optima Control Solutions, an independent automation expert, designed and supplied a new control system for the Doncaster based hot dip galvanizing line. Performance, flexibility and safety were at the heart of their design considerations.

Arron Woodiwiss, Bridon Doncaster’s electrical project engineer comments: “Cost was only one of the factors in favour of choosing Optima. We have worked with them in the past and they have demonstrated the experience and the specialist expertise that we were looking for.”

Optima’s task was to supply the controls for 8 new Vertical Take Up units. Arron told us: “Production requirements for increased piece weights demanded increased performance and capacity. Bridon designed and managed the manufacture of 8 new VTU units to replace existing equipment. Operational benefits associated with larger weights would include less handling, longer run times and therefore improved Plant OEE. Obsolescence of the existing control equipment did play a smaller, though important part of the justification”.

Optima’s solution employed a total of 16 Leroy Somer AC motors (8 capstan motors and 8 turntable gear motors). In order to control the speed and torque of these motors accurately during the galvanising process, Emerson’s “Control techniques” AC drives were used. Any variation in the speed of the wire in the galvanising tanks would have resulted in non-uniformed coating of the wire. This in turn would have resulted in unsellable product being produced.

Working closely with the production personnel, Optima supplied an ergonomically designed operator control interface using Siemens S7-300 PLC and Siemens TP177 Micro HMI.

A complex emergency stop system was also designed to provide safe machine access with minimum production disruption. Optima’s final task having engineered the advanced PLC, drive and safety control system was to commission the whole project.

The control system installation and commissioning was completed in a very short time period over the Plants summer Shutdown period minimising additional production disruption, always a critical element for manufacturers.

The project realised a number of improvements for Bridon International; these included reduced product changeover times, better production performance, higher availability and increased product quality. Arron Woodiwiss explained “The upgrade extended the production line performance rates, consequently we now enjoy better competitiveness. Through improved process control we were able to expand the product range, as well. Overall, Optima delivered a control solution on time, on budget and our production performance increased as expected”.