(EN) A Visit to the Fendt Cabin Plant in Asbach-Bäumenheim—Part 1

Recently, I had the chance to visit the Fendt Cabin Plant in Asbach-Bäumenheim (between Stuttgart and Munich) thanks to an invite from Tarik Kadrispahić from Targer Consulting (Thank you, Tarik!). I’d previously had the chance to see their main plant in Marktoberdorf, and I liked it a lot. Hence, I entered their plant in Asbach-Bäumenheim with high expectations. And Fendt did not disappoint! In this first blog post of this series, I will look at the plant in general, and the details of the assembly line.

Introduction

Fendt is a well-known German maker of agricultural machinery, making tractors, combine harvesters, balers, telescopic handlers, row crop planters, and more. Founded in 1930, it is now part of AGCO Corporation. I previously visited their main final assembly plant in Marktoberdorf, Germany, and really liked it. Their challenge is the huge product variability, making anything from tiny vineyard tractors to huge vehicles for large-scale agriculture. As well, some of them are battery-powered fully electric ones too. They use quite a few ingenious tools to manage this variability, which they call Variable Takt or „Vario Takt.“ I liked this so much that I wrote three blog posts about it.

Fendt produces the final tractors in Marktoberdorf, and receives the cabins from their supplier plant in Asbach-Bäumenheim, near Stuttgart, Germany. AGCO has around 24 000 employees worldwide, of which 8000 work in Germany (mostly for Fendt) and 1400 of which are in the tractor cabin plant in Asbach-Bäumenheim. The cabin of modern tractors is a complex product and can be quite luxurious. After all, the farmer may work up to sixteen hours per day within such a cabin during harvesting season.

Cabin Production in General

This plant is the worldwide „Cab Center“ and produces cabins and hoods, mostly for the tractor plant in Marktoberdorf, but also some other plants worldwide. Their production includes sheet metal processing, bending, welding, and painting, but our focus was on the final assembly line of the cabins.

At the time of our visit, they produced around 150 cabins per day in two shifts (6:00–14:00 and 14:00–22:00). The current line could produce 200 cabins per day, but runs at reduced capacity due to the lower demand. This adjustment was done by adjusting the number of operators on the line, spreading the same work on fewer operators for a slower takt. Nevertheless, an expansion to a capacity of over 300 cabins per day is envisioned. At two shifts, the line produces a cabin at a takt of 9 minutes per cabin. Previously, the line ran with one shift only, producing a cabin every 4.9 minutes. Interestingly, when they reduced from one shift to two shifts, they lost around 5% efficiency. Efficiency generally drops with slower takt times (and improves with faster takt times). The 5% drop fits very nicely with my own model connection efficiency with takt times.

No matter what end product the cabin was for, they were all produced on the same assembly line. Hence, this assembly line also had considerable variety, as the size of the cabin varies widely. The sequence was mostly determined by the main plant in Marktoberdorf, which needs to influence the sequence to manage the product variety (generally, a product with a lot of work for one station should be followed by a product with less work for the same station, to avoid overload). Nevertheless, Asbach-Bäumenheim could also have some say in the sequence, and one of the rules was not to have two seats of a certain type (sideways, I think) directly after each other, as this would overload some of their stations. The sequence of the cabins had to match the sequence of the main tractors, and hence this is a good example of Just in Sequence (JIS) production. The demand was frozen eighteen days ahead, albeit the sequence was only formed five days ahead. Currently, sequencing is still done in Excel, but they plan to switch to a dedicated sequencing software by the German vendor Tactiq.

There was also not an excessive buffer between the cabin production in Asbach-Bäumenheim and the usage of the cabin in Marktoberdorf (roughly a two-hour drive by truck, depending on traffic). They have usually around 100 cabins of buffer and transport between the two plants, representing less than a full day’s worth of production, and they try not to fall below 75 cabins in the pipeline between the plants. However, when I visited they had only 50 cabins in the pipeline, which was a bit too few for their comfort.

The Assembly Line in Detail

Like the tractors in Marktoberdorf, the cabins in Asbach-Bäumenheim moved through the factory on automated guided vehicles (AGV). Regardless of the size of the cabin, the same AGV was used (only for the section where the top and bottom were split; the top used a different AGV, see below).

Components were also assembled in the plant on sub-assembly lines that joined the main assembly line just in sequence. For example, there was a separate assembly station for the plastic roof, containing the lights, antennas, and much more. When the freshly painted cabin arrived at the final assembly line, the first step separated the lower part of the cabin (seat, dasboard) from the upper part (mostly roof support and doors) into two separate assembly lines. This made it much easier to get parts into and assemble the two separate halves. The AGV of the lower part could also rotate the (half-) cabin to make it easier and more ergonomic for assembly. All AGV could lift the cabin up or bring it back down to simplify the assembly process and make it more ergonomic. The upper part of the (half-) cabin could be walked in, since there was no seat and dashboard in the way. A few stations later, these two halves were merged again using a crane (obviously, also just in sequence). A very simplified sketch is shown below.

The assembly stations looked very well organized. Many of them had custom-made tool carts that were moving along with the line. The carts themselves were constructed from pipes with matching connectors (not the more expensive aluminum profiles). Some carts were pushed by the AGV, others were pulled by the AGV. Often, both sides were used, to supply both the previous and the next cabin on an AGV with material, as sketched below. The carts often stayed with the AGV for only one or two stations before being removed and pushed back to the next AGV by hand. This is quite doable with a 9-minute takt time. Regardless of the cabin model coming down the line, the same tool cart was used. All these carts looked quite well organized. For example, tools that were used for only certain models of cabin were color coded to reduce mix-ups. The cart before and after the quality control had a mirror so the operator could better see whether the lights were working or not. I believe many rounds of shop floor–based improvements iterated over this design. I also believe, if I would visit now, the carts would again look slightly different.

As in Marktoberdorf, the use of AGVs gives a lot of flexibility. For example, if there is a problem at one station for one cabin that cannot be fixed right now (e.g., a missing part), the AGV can simply drive the cabin out of the line and wait on the side for the problem to be resolved (e.g., the missing part to arrive). However, this will cause a lot of other subsequent problems, not the least is that Marktoberdorf wants that cabin in this sequence for their own tractors. Luckily, according to Fendt, this happens very rarely, and there was a lot of support to solve problems on the line before the cabin moves to the next station.

In my next post I will dive deeper into the topic of efficiency, line balancing, and shop floor management at Fendt in Asbach-Bäumenheim. Now, go out, have a good look at your assembly process, and organize your industry!

PS: Many thanks to Tarik Kadrispahić from Targer Targer Engineering & Consulting for inviting me to come along on his excellent tour of Fendt and other plants!