A Die-Cutter Like No Other
In past blog posts we have written on Eli Goldratt’s Theory of Constraints and the related challenges packaging converters are now facing with quick set-up high-speed press equipment burying their finishing departments with WIP (work in progress) inventory. The advancements in press technology have moved the bottleneck downstream to the die-cutting and folding gluing departments. In order to avoid these potential bottlenecks, we made our most recent equipment acquisition, a technological marvel from Bobst: The Expertcut 106 PER.
For those not familiar with the Theory of Constraints, its primary purpose was to enhance traditional accounting methods with easy to understand measurements of costs, inventory, and throughput. It developed a framework that gave manufacturing operations a better understanding of the ramifications for decisions made on the shop floor. By measuring throughput, you focus on the total time and speed for turning jobs from order entry to the receipt of payment. Buying a high-speed press can cut make-readies in half as well as significantly reduce run-times, but its total benefits aren’t being realized if it is creating loads of WIP that may end up being staged for days (or weeks) if they can’t get through the next operation in a timely manner. The true benefit of a quick-turn press is reduced material make-ready, which is a real cost. The time savings for a single department aren’t realized unless they reduce the throughput time: local vs. global optimization.
In their exceptional report commissioned by PRIMIR®, Packaging: Evaluation of Vertical Markets & Key Applications, Karstedt and Partners insightfully touch on this finishing bottleneck issue in their examination of the challenges packaging converters face in the new economy. They state that carton manufacturers “need to more effectively manage production orders that are shrinking in size and increasing in frequency”. They go on, “This is simply not obtained by purchasing presses that have quick changeovers. This plan moves a bottleneck from on process step to another. Carton converters are searching for solutions that transform their operations for the better.”
Taking liberties with the old phrase ‘a skeleton in the closet’, we have our own skeletons to deal with – the leftover waste from a die-cut sheet. This skeleton has been one of the biggest obstacles in improving die-cutting speeds. In standard die-cutting “nicks” are added to the cutting rule to hold a cut and scored sheet together as it moves through the machine to the delivery. More advanced die-cutters have blanking capability – the ability to strip away the skeleton entirely, sending only finished ‘blank’ product to the delivery.
The Bobst Expertcut 106 PER has the capability to run both standard and blanking capabilities, handling both cutting methods very effectively. A totally redesigned feeder utilizing a multiple suction system helps to provide better sheet separation and control into the die-cutter. The optical detection system replaces traditional guides and grippers for more accurate registration – print to cut. A precision machined cam driven platen system guides the sheet through the press at a higher speed, while also reducing wear of the cutting tools. The integrated Quick Lock tooling system leads to faster and more accurate set-ups.
Through the combined innovation of Bobst, the original equipment manufacturer, and the Impressions’ Process Engineering team, we have put into effect a total production optimization plan of improving total throughput of our manufacturing process from file management to finishing. We’ve invested extensively in automated business information systems, digital printing, and quick-turn technologies in both printing presses and folder-gluer machines. By adding this new die-cutting capability, we have found the missing piece in the puzzle. We invest wisely to reduce inventory, increase throughput, and lower costs, we believe the latest addition to our plant will do just that. The Expertcut 106 PER is truly a technological marvel!