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- Changeover time depends on which product you change from and to.<\/li>\n
- A changeover matrix holds the duration for each pair, ramp-up included.<\/li>\n
- It should rest on measured changeovers, with median and spread.<\/li>\n
- Sequencing then works with the reality of the line.<\/li>\n<\/ul>\n<\/div>\n
What Future Factory writes about changeover times<\/h2>\n
Fanny Dobrenova wrote R\u00fcstzeiten minimieren oder optimieren? Finden Sie die goldene Mitte<\/a> (“Minimise or optimise changeover times? Find the happy medium”) for Future Factory GmbH, an ERP software vendor for manufacturers based in Graz, Austria. She sets technical and organisational measures side by side, from SMED to planning the job sequence, and argues for a middle way between fast changeovers and clean results. On the role of data, she writes: “Die Analyse der im ERP-System verf\u00fcgbaren Daten erm\u00f6glicht die effektive Planung von R\u00fcstzeiten.” (Analysing the data available in the ERP system enables effective planning of changeover times.)<\/p><\/blockquote>\n
The article brings the planning view: group products with similar properties and run them one after another, move changeovers into periods of low load, sequence jobs sensibly. This article adds the line view: which changeover times does planning work with, and do they match what actually happens during the changeover? A sequence is only as good as the changeover times behind it.<\/p>\n
Why one changeover time per machine is not enough<\/h2>\n
Many master data records hold one changeover time per machine or per item. In practice, the duration of a changeover depends on which product you change from and which product you change to.<\/p>\n
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- Changeover within a family.<\/strong> Often only parameters or stops are adjusted. The changeover is short and easy to plan.<\/li>\n
- Change of material, colour or recipe.<\/strong> Cleaning, purging or quality release are added. The duration depends heavily on the direction, for example light to dark or the reverse.<\/li>\n
- Format change with tooling.<\/strong> Tools, moulds or guides are swapped. This is where most of the changeover time sits.<\/li>\n
- Ramp-up after the changeover.<\/strong> It takes more time before the machine runs stably at nominal speed and makes good parts. This time is missing from many planned values.<\/li>\n<\/ul>\n
For example, on a packaging line, switching between two formats of the same family is quick because only settings change. Switching to a different film, on the other hand, means cleaning, adjusting and a trial run. If planning works with an average value, every sequence looks equally good on paper, and exactly the information that would make one sequence better is lost.<\/p>\n
![\"Four](\"https:\/\/teeptrak.com\/wp-content\/uploads\/2026\/11\/teeptrak-ruestmatrix-en.png\")
<\/figure>\nThe real changeover matrix: from which product to which<\/h2>\n
A changeover matrix records, for each pair of preceding and following product, how long the changeover takes. To really help planning, it should rest on measured changeovers and hold more than an average.<\/p>\n
- Change of material, colour or recipe.<\/strong> Cleaning, purging or quality release are added. The duration depends heavily on the direction, for example light to dark or the reverse.<\/li>\n
- Changeover within a family.<\/strong> Often only parameters or stops are adjusted. The changeover is short and easy to plan.<\/li>\n