Van Delft: towards more efficient production and less waste with Sensorfact OEE

The start

Van Delft’s production department faced a common challenge: manually tracking Overall Equipment Effectiveness (OEE). Operators recorded downtime in time-consuming five-minute blocks, which led to a lot of resistance and high registration pressure. This method was not only inefficient but also failed to provide detailed insight into actual losses. There was a great need to automate OEE and concretely map out losses, making it clear where inefficiencies were increasing on the line. Johan de Jong, Production Manager and CI Manager, saw an opportunity to improve efficiency by measuring where the loss lies between what can be maximally produced and what actually comes off the line – the core of the three OEE pillars.

The solution

Van Delft chose to implement an OEE solution together with Sensorfact. Sensorfact’s openness to collaboration and improvements was the decisive factor, leading to a joint effort in building what is now the ideal OEE toolkit for Van Delft. The primary goal was to be able to measure OEE, but the implementation also made it possible to see the difference in production efficiency between machines, even within a single production line.

The solution involved placing three photocells per machine, totaling six for the two linked machines on the production line:

• The first photocell registers the input of biscuits.
• The second photocell counts the number of stacked biscuits (two on top of each other). Ideally, this should measure half the number of the first photocell and is placed at the input side of the packaging machine.
• The third photocell is located at the output side of the packaging machine and counts the number of packaged biscuits. This number should be equal to the second photocell.

The difference in counts between these photocells provides direct insight into waste and/or rejects at each step of the process. Crucially, an alert is triggered when photocell 3 measures nothing while photocell 2 is registering. This means good biscuits are being ejected instead of packaged. In such cases, or if one of the photocells stops for longer than two minutes, operators must indicate the cause of the deviation. This provides immediate insight into short but frequent stops. Additionally, Van Delft actively collaborated on the development of quality measurements and batch management, enabling detailed insights and standards per product. This demonstrates how Sensorfact continuously develops its solution in consultation with and based on customer requests.

The results

The implementation of Sensorfact OEE has led to measurable improvements and a cultural shift at Van Delft:

• Targeted machine optimization and higher speeds: The OEE data clearly showed that the biscuit supply to one machine was suboptimal, causing it to run slower. A simple adjustment to the settings, based on these insights, directly resulted in faster and more efficient machines.
• Effective approach to short stops: One of the diagrams in the software showed that short stops had a significant impact. Now, operators record the reason for every short stop within two minutes. This led to practical solutions such as targeted attention cards and using more meters of wrapping film on a roll, resulting in less changeover time. The graphs visualize the data, convincing operators with facts and encouraging their input: “An ‘oh, that’s not so bad’ thought changes to ‘hey, that happens quite often’,” notes Johan. This results in a significant reduction in short production stops and proactive action from operators.
• Proactive maintenance and less unplanned downtime: Detailed registration of stops enables preventive maintenance. For example, if a conveyor belt has broken three times, Van Delft proactively replaces it after a certain period. This prevents unplanned downtime and results in less production loss and a more stable production process.
• Automatic waste calculation: The OEE solution now automatically calculates waste (output – input), which was previously manual, time-consuming, and often unreliable. This automated measurement provides crucial real-time insight into our waste streams, which is essential for continuous optimization.

Johan de Jong is very positive about the collaboration:

“Sensorfact listens carefully to customer needs; you get what you ask for. The graphical visuals are excellent: nicely clear and logically structured.”