Materials Handling Profile
Robotic palletising system delivers superior safety standards for Australian manufacturer.
Incorporating a robotic palletising system into its new production line ensures that occupational health and safety issues are never a problem.
As a world-class company with a history of strong growth and a string of leading brands behind it this leading Australian manufacturer was clear on three points when it came to the automation of its new production line at its manufacturing facility in Sydney: eliminate occupational health and safety issues; reduce labour costs; and increase production capacity. Integral to the automation of the production line and its three new packing machines would be the installation of a palletising system that could deliver on those three key points: a challenge in any industry involving palletising, where manual systems are notoriously labour intensive, time consuming and plagued with the occupational health and safety issues associated with heavy lifting.
Robotic palletising at work
The system principle delivered by Machinery Automation & Robotics (MAR) is simple:
automate carton handling; automate pallet handling; automate stretchwrapping; install a single robot system to perform the process; design a user-friendly touch screen; and the entire palletising system can be controlled by a single operator.
At system start up the operator loads a stack of up to ten empty pallets into each of the Chep and Export pallet stack frames. These pallets – of which 20 can be accommodated at any one time – are then automatically conveyed to the pallet pick-up position. Using the PanelView touch screen the operator determines the criteria by which the system will function. After ensuring that no personnel are within the cell the operator closes the switch-protected safety gate and uses the PanelView touch screen to start the robot system.
The robot system, which provides continuous operation during the palletising process, comprises a robot which distributes the empty pallet stacks to the loading stations. If required at this stage, the robot picks and places a pallet layer sheet onto the appropriate empty pallet. As cartons are received at the infeed conveyor sensors count the required quantity to commence pallet layering. When the correct number of cartons is reached, a stop plate prevents additional cartons from entering the final pick-off point. Moving to the carton infeed conveyor the robot grips the set of cartons and raises them from the conveyor. Following system confirmation that the cartons are securely gripped the robot transfers the cartons to the loading station and continues the palletising process until a pallet load is complete.
Each fully loaded pallet is removed from the loading station to the 90-degree conveyor transfer, from where it travels along the main trunk line before exiting the cell through the muted safety light curtain. The pallet then enters the stretchwrapper where, if preselected by the operator at the PanelView touch screen, it is wrapped prior to exiting the system for the pallet pick-off point.
Design of the robot palletising system provides the flexibility of manual stretchwrapper infeed in addition to the fully automated process. The pallet conveyor section between the robot cell exit and
the stretchwrapper entry points allows pallet placement by a forklift operator for automatic stretchwrapping. The break in the light curtain created by the forklift operator entering the area powers down the section, enabling the pallet to be placed on the conveyor. The driver simply presses the reset button as he clears the light curtain to activate the conveyor section.
All completed pallets exit the stretchwrapper, whether preselected for wrapping or not, and are ready for removal by the forklift operator. In a similar process to the manual stretchwrapper infeed system the conveyor is powered down by a break in the light curtain, the pallet is loaded and the forklift driver exits the area and reactivates the conveyor section with a simple push of a button.
Control at your fingertips
Operation of the entire robotic palletising system and conveyors is controlled from the colour PanelView 700 Human Machine Interface (HMI) touch screen located inside the robot enclosure. The ten-page PanelView program is easy to navigate and includes primary control for system start/stop function and a graphical display to assist the operator. In addition the program provides a dedicated page for each of the following: manual control of conveyors; manual control of the gripper; shift production data; error reporting; robot control in service position; and robot control in the elevated home position, maximising access around the cell during maintenance and cleaning operations.
The PanelView touch screen program also incorporates a number of selection options enabling the operator to determine: carton tuning to allow for changes in card production and case packing tolerances; the products to be palletised; the number of carton layers per pallet; the pallet station to which the product is to be transferred; the type of pallet – Chep or Export – to be used at each station; whether a pallet sheet is to be used at each station; and, finally, whether a completed pallet is to be stretchwrapped.
Safety first
The automated system upgrade enabled two specific features to be incorporated into the design of the system cell: firstly, that no part of the robot or gripper make contact with the perimeter fence or the four surrounding walls; and secondly that the area within the cell be maximised to ensure free access around the robot and conveyors for cleaning, maintenance and general operation.
Adding up the benefits
Automation delivered a range of benefits including:
• The manufacture, supply, installation and commissioning of a complete robotic palletising system
• Elimination of all manual handling during palletising operations, resulting in significant labour-cost savings and adherence to occupational health and safety standards
• High-speed palletising, processing up to three cartons per cycle and completing a minimum of eight cycles per minute
• Incorporation of four separate carton infeed conveyors and four pallet-loading stations within a single cell
• Flexible palletising – both Chep and Export pallets can be processed simultaneously within the cell
• Incorporation of a fully automatic stretchwrapper system
• A user-friendly, customised PanelView Plus 700 HMI
• An increase in production capacity due to the fully automatic upstream packing systems
Texi-Pave
Total automation solution for paving specialist forecasts impressive return on investment in less than two years.
Investment in a fully automated system to overhaul a largely manual wet-cast moulding operation results in immediate productivity increases, quality improvements and a significant reduction in running costs for paving and pool coping specialist, Texi-Pave.
After 30 years in the paving and pool coping business, Texi-Pave hav
e seen many changes to the common concrete and brick paver. In today’s sophisticated – and rapidly growing - DIY and renovation market customers insist upon an increasingly wide range of colours and dimensions when selecting pavers and demand for product consistency and finish is high. A technologically advanced production process is the key to eliminating costly product inconsistencies due to air inclusions in wet-cast concrete mouldings and increasing output to meet burgeoning market demand. Identifying their need to maintain an edge in a highly competitive market Texi-Pave made a significant investment in a total automation solution for their existing manual wet-cast operation with major improvements to product quality and output as well as an impressive return on their investment.
Making light work of manual labour
Any manufacturing industry that is heavily reliant on manual production processes faces constant labour, safety and quality control challenges. At Texi-Pave continuous de-stacking of empty trays and transfer of heavy wet-cast concrete moulds onto pallets by hand, along with manual tray lubrication with oil mist spraying equipment were causing serious occupational health and safety issues for the company. By automating the entire wet-cast operation Machinery Automation & Robotics (MAR) successfully integrated electrical, pneumatic and robotic equi pment to eliminate all heavy manual lifting and a fully automated oil mist unit to reduce the potential hazards of manual oil mist spraying. In addition, three fully automated vibration tables were included in the process to effectively remove air inclusions from the concrete cast, replacing the existing manually operated vibration table and ensuring a consistently high quality finished product.
Realising rapid returns on capital investment
The benefits of automating an existing manual system at Texi-Pave proved twofold. A production line previously operating with six staff members in each shift was immediately reduced to a one-man operation significantly alleviating labour costs. The elimination of all manual heavy lifting has minimised costly product damage caused by dropping and knocking trays during transfer and concrete spillage. And for a business averaging a 100% turnover of staff every year, savings in employee training have proved considerable.
Financial savings, however, haven’t been the only benefit. No longer requiring production to stop for mandatory employee work breaks, Texi-Pave operate their automated wet-cast operation continuously throughout the daily shift increasing output without extending operating times. And with robots operating at higher speeds than a manual workforce overall productivity has seen significant increases. Existing capital plant assets, including the mixer and silo storage, have also been more fully utilised. The batching system, where sand, colouring and cement are mixed, and the mixer are better utilised following the introduction of a robot, which transfers more trays onto pallets than were processed manually.
Automation at work
The solution provided for Texi-Pave has automated the production process from the handling of empty trays through the wet-cast moulding process to the transfer of full trays and pallets at completion of the operation. A single forklift operator loads empty trays stacked fifteen high onto the new chain conveyor, designed by MAR to replace an existing antiquated belt system conveyor. The trays are then transferred to a fully automatic de-stacking station where electrical and pneumatic controls handle their separation into individual trays. The operator, who has simple push button control over the conveyor, places the moulds into the trays as they move along the conveyor. The trays then pass through the automated oil mist unit on the inline conveyor to prevent the product from sticking to the mould.
A dosing machine dispenses concrete from the batching system into the moulds. During the dosing process the trays sit on the first of three new vibration tables, which form part of the indexing (transfer) system at the end of the line. The automated vibration action removes air from the concrete as it sets. To ensure the quality of the finished product is consistently high and free of air inclusions the trays then pass over a second and final vibration table before arriving at the robot palletising area.
The robot at the palletising area is capable of picking up three full trays simultaneously and placing them into a single pallet at the loading station. The pallet at the loading station is then stacked with fifteen trays before being dispatched to the unload station where the forklift operator removes the pallet from the system. The pallet stacking station and infeed conveyor supply batches of ten empty pallets to the robot operating area where accumulation of up to twenty empty pallets is possible. The pallets are then transferred one at a time to the loading station conveyor as required.
Adding up the benefits
The transition from a manual operation to an automated one brings with it many changes to any business involving production processes. For Texi-Pave the changes initiated by the introduction of a total automation solution brought with them many benefits. These include:
• A complete automation solution including design, programming, installation and commissioning
• An ROI in less than two years achieved by a reduction in labour costs, an increase in productivity and an improvement in product quality
• Onsite commissioning alongside Texi-Pave’s existing operation with only minimal disruption to production during a one-day installation
• A general robotic training program completed at MAR’s technical facility followed by onsite application-specific training tailored to Texi-pave’s specific needs
• Full compliance with occupational health and safety requirements
Technology at work for Texi-Pave
• The control system features an Allen Bradley CompactLogix PLC and serves as the gateway between the Ethernet and DeviceNet networks
• A single operator controls the line via an Allen Bradley PanelView Plus 600 key colour HMI (Human Machine Interface) running on the Ethernet network
• The entire production line is driven by twelve Allen Bradley Power Flex variable speed drives
• All remote input and output nodes are controlled via the DeviceNet back to the PLC
• The KR 180 PA KUKA robot was selected to undertake all depalletising and palletising tasks, controlled via the DeviceNet and PC driven on a Windows platform
• Three vibrating tables at the end of the production line form part of the indexing (transfer) system and are driven by variable frequency drives, allowing infinite adjustments via the touchscreen HMI