Robot control brought to tissue packing line

The plant in Bridgend near Cardiff has both tissue making and converting operations. Packing and dispatch of the finished products is a complex operation because the company produces many different sizes of multipack and these are arranged on pallets for transportation in a great many different patterns.

The production hall is used for packing and has a shuttle conveyor to deliver batches of products to one of two robotised palletising stations. Northwood and WEPA brought in electrical and automation specialist Platinum Controls from nearby Neath to work on the control systems.

Stephen Vincent, Technical Director of Platinum, recalled how the project developed and said: “We reviewed the site and looked at options for control solutions. One of our key recommendations was to use a flexible but competitively priced SCADA (Supervisory Control and Data Acquisition) package.”

Vincent continued: “The one we recommended was Movicon made by Progea in Italy and available in the UK exclusively through Products4Automation (P4A), with whom we have worked on several other projects. We have always found the Movicon product to be very cost competitive yet highly functional. It is also easy to programme, install and commission, so saves us time in commissioning.”

Robots have become increasingly popular for palletising duties in recent years because of the weights they can lift without risking repetitive strain injuries and the productivity levels they can achieve. This is coupled with their ability to execute a number of different loading patterns and the flexibility to change quickly from one product or sequence to another.

The system designed by Platinum Controls is based on Movicon SCADA technology. It controls the robot’s programs from a database of many different pallet filling patterns which are chosen according to the size and shape of the multipacks being palletised and/or to meet individual customer preferences.

The operators interact with the robots via an industrial keyboard and a 21” touch screen monitor mounted on the electrical control panel. At these they are able to enter a password and easily select the required stacking pattern. They are also able to develop and store new stacking patterns from the control panel, which previously had to be done by the production/engineering team.

“These new patterns are stored in the database under names added by the operators themselves, rather than using long reference numbers,” said Vincent. “This small change has proved popular and effective because the reference numbers were difficult to remember, whereas the names are completely intuitive.”

The hardware used in the control system includes two PLCs (programmable logic controllers), one communications driver, 9211 I/O and a PC that can display over 50 different information screens.

Movicon is a SCADA solution based on XML and Web Services technologies, making it easy to understand and intuitive to use. Its modular design allows bespoke systems that meet the exact needs of each application to be built quickly and simply. As it is almost inevitable that applications need to change, develop and grow over time, Movicon’s developers were careful to make sure that expansion and alterations to systems are also straightforward.

Products4Automation’s Paul Hurst said: “Movicon is designed to improve productivity, reduce integration times and operating costs, and to optimise asset utilisation.”

Hurst added: “We sell it as a pure software package, or installed on an industrialised PC or HMI product. Fast control and visualisation, in addition to good data recording made it an ideal choice for the palletisation application.”