Tile manufacturer gets increased flexibility from heavyweight robot with a sensitive touch

Citation

(2003), "Tile manufacturer gets increased flexibility from heavyweight robot with a sensitive touch", Industrial Robot, Vol. 30 No. 1. https://doi.org/10.1108/ir.2003.04930aaf.001

Tile manufacturer gets increased flexibility from heavyweight robot with a sensitive touch

Tile manufacturer gets increased flexibility from heavyweight robot with a sensitive touch

Keywords: Palletising, Packaging, Robots, FANUC

Meeting customer’s fashion requirements in high volume markets presents great demands on manufacturing to be flexible and to be able to adapt quickly. Falling into this category is the roofing tile market where Marley Building Materials (MBM), a major player with eight UK manufacturing sites, understands the need to offer an ever-widening variety of products.

When a new “slate look-a-like” concrete tile was recently introduced into MBM’s range it presented the need for a complete review of the packaging area at its Beenham site. Unlike the “traditional” concrete tile, which has an even thickness over its area, the new tile has a thin leading edge which made it difficult to stack or strap using the existing equipment.

Steve Herriott, Project Manager, MBM, explains, “Automated systems within our facilities are an essential part of our process. The existing ‘dedicated’ automated equipment had been operational for the past 15 years and was originally designed to package 120 tiles per minute (TPM). Improvements carried out in the rest of the plant over the last few years have increased the handling requirement to a rate of 150 TPM at 80 per cent utilisation. Although modifications to the original packaging equipment could have made this feasible, the costs could not be justified.”

Following the successful installation of a robotic system over a year ago in another area, MBM had the confidence to investigate the robotic packaging route for this line. After an appraisal of several robot suppliers, MBM placed an order with FANUC Robotics for the system supply which included two 4 axes FANUC Robot M-410iWW palletising robots, grippers, guarding and overall responsibility for interfacing all associated plant.

“Overall system integration had the potential for particular problems”, continues Herriott. The tile delivery point to the packaging area, from the existing system, required modification together with the installation of two new strapping machines. These elements and the robotic system, plus our own engineering department’s involvement meant that four companies were involved in the installation. Previous experience of working with FANUC in similar situations told us that they were very capable of integrating all the equipment and most importantly – sticking at it until it was working effectively.

The two FANUC robots, each capable of lifting 400 kg at ±10.5 mm repeatability, are positioned either side of the strapping area. The tile conveyor operating at up to 150 TPM delivers tiles to two pick-up points where they are orientated and positioned for the robot’s gripper to locate. The weight being handled at this stage is a combination of tile pack at 170-200 kg and gripper weight of 175 kg (see Plate 1).

The tile packs are then positioned either in one of twelve buffer storage areas, to allow production to continue if there is a line stoppage, or taken directly to the strapping machine. Once strapped the tile pack is picked up by the palletising robot and lowered towards the programmed pallet position.

Plate 1

Steve Capon, FANUC’s Project Manager, explains, “The nature of the product being palletised meant that we had to allow for large tolerances but still work at relatively high palletising speeds. When positioned on the pallet the tolerance build-up of tile pack and pallet can be anything up to ±25 mm. The palletising gripper uses a sliding plate that locates under the pack and pulls out when the tiles are located on the pallet. To overcome the tolerance problem, imposed by the wooden pallets, we used our High Speed Skip software. This allows us to drive the robot at speed to within 25 mm of the stack and then reduce speed to 100 mm/s while monitoring motor current every 20 ms. When the gripper plate contacts the stack, current increases and the robot programme instantly skips to the next programme step.”

The system has now been in operation for several months and is operating at close to 150 TPM. Steve Herriott summarises, “Already we are seeing benefits from the new packaging equipment. The system delivers a much firmer package which for our customer’s means less breakages during shipment and overall a higher quality product. Reduced profile changeover times, increased reliability and flexibility of the system have all contributed to an improvement in utilisation in this area.”

For further information, please contact: Maurice Hanley, National Sales and Marketing Manager, FANUC Robotics (UK) Limited. Tel: 024 7663 9669; E-mail: sales.fruk@fanucrobotics.co.uk; Web site: www.fanucrobotics.co.uk