The Grand Tour of German Automotive—Mercedes-Benz Bremen

The second plant of Mercedes-Benz (also known as Daimler) in my Grand Tour of German Automotive was their plant in Bremen. This was also their second final assembly plant. It produces a few cars more than Sindelfingen, and hence claims to be the largest Mercedes-Benz plant by the number of cars. It was also a good and interesting visit. Keep on reading…

Disclaimer: The following is based on my personal observations and opinions and may not be accurate or correct. It is based on publicly available information and what I observed during public tours, and when I observed it. The observations may differ at a different time and place.

Introduction to Mercedes-Benz Bremen

The plant was established in 1938, albeit Mercedes-Benz joined as a shareholder only in 1969, and took over the plant completely only in 1978. The plant has 11 500 employees, 8300 of whom are involved in production. As the plant was established almost 100 years ago, the back-then greenfield location is now in the middle of the city. Hence, expansion is difficult, and the plant is growing upward. For example, trucks drove up a ramp and delivered parts two floors up from the ground floor.

The plant produces the C-Class, CLE Coupe and Cabrio, GLC including the coupe, the AMG SL roadster, the AMG GT, and the fully electric EQE. Like Sindelfingen, it produces around 300 000 cars per year, but the plant claims that is the largest of Mercedes-Benz by number of cars produced.

The plant had three body shops and three separate assembly lines. I visited the line for the CLE cabrio, the CLE Coupe, and the C-Class. Like Sindelfingen, the takt time was confidential, as was the lead time (which strangely enough was not confidential in Sindelfingen), and the employee bonus system. You had to lock away your phones in lockers for the tour.

Body Shop & Paint

There are three body shops in Bremen. As everywhere in high labor–cost countries, the body shops are highly automated, with 95% of the work done by robots. While I visited, the body shop faced some challenges with supply chains due to the general state of the world.

The takt of the body shop is a secret, but I estimated a takt of around 50 seconds. One of the many andons gave a daily target of 998 car bodies. 500 cars per shift also fits my estimate of a 50 second takt. Normally they run in three shifts, but this is currently reduced due to external factors.

Logistics was done mostly by forklifts, but overall, the body shop looked quite clean to me, cleaner than at Audi or VW. We also saw a team corner, and that looked quite active to me. Many team corners have many static printouts that nobody ever looks at, but at Mercedes in Bremen, there were signs of a lot of engagement of the workers with the data with handwritten notes and feedback.

The body shop employs a triangular fixation tool that can be rotated for different models. The body shop aims to reduce the number of spot welds to save time and energy. They claim that every spot weld less saves 0.3 seconds. They also press QR codes into the sheet metal to identify the car bodies. The body shop also has a quality control system that detects welding defects in the car bodies… which may not quite work as well as we on the tour already saw at least one larger welding defect, where the robot put a weld line for a structural part almost one centimeter off to where the part actually was. We informed a quality person about our findings, so hopefully the problem was fixed before the car was sold.

After the body shop was the paint shop, which we did not visit. From there, three body sorters sorted the car bodies into three different assembly lines.

Final Assembly Hall 93

We visited the assembly line in Hall 93 for the CLE cabrio, the CLE Coupe, and the C-Class. Due to the space constraints, this assembly line was also two floors up from the ground floor.

The takt time was again secret, but I estimated around 130 seconds per car. The andon had a target of 177 cars per shift, which also fits the 130 seconds per car takt. The lead time, unfortunately, was also secret. I also estimated the percentage of the time the worker adds value to the car at 43%, which is around average for German car plants (see my blog post How to Estimate Value Add for Manual Work for more).

A lot of the material was transported using AGVs, but there were also still some forklifts. Some of the car bodies were also transported on AGVs, which is still found mostly in newer assembly lines.

Even during normal operations, we saw workers walking ahead of their stations quite a few times. We saw a worker walking across three stations to get material, which he then carried back three stations again to install. This looks like quite some working ahead. We also saw the opposite, where a worker underneath the car had trouble completing his tasks, and was moving away from his station together with the car body. Unfortunately for him, this was the end of the underbody section, and the car was getting closer and closer to the floor. At the end, the employee was duck-walking while assembling in the small space underneath of the car. I forgot to ask if they had an andon line, but even if they do, it is apparently not used. In any case, this felt unsafe for me.

We also observed one car on the assembly line with a visible dent, which the guide said was the first time in ten years that he saw one on a tour. Still together with the welding error in the body shop that makes two errors… but maybe we only saw this because we were allowed directly on the assembly line.

The cars also had a prominent build manifest, which Mercedes keeps for twenty years. The employee marks errors directly on the build manifest. I did notice that the build manifest was placed on different locations, sometimes on the dashboard, sometimes on the floor between the (to be installed) seats, sometimes near the brake pedals, sometimes on the (now installed) seat, etc. Not sure if this was by design, but it felt somewhat random to me.

The group size was rather large of around 30 people, but this included a Meister, a group responsible, and three springers, which effectively makes a span of support a more reasonable 8–10 people per springer… but still larger than the 4–5 people per team leader at Toyota. As in many automotive final assembly lines, only 8% of the employees were female. The early and late shift rotated, but the night shift was a permanently assigned night shift (“Dauernachtschicht”). Employees liked that, because you get more money at night. As with many other plants, lights were dimmed at the stations during breaks.

On a side note, we had dinner in the nice restaurant in the customer center, where customers dine before they pick up their new Mercedes. Strangely enough, the salt and pepper shakers featured a very prominent Peugeot logo. The waitress told us that they are merely a restaurant licensed by Mercedes-Benz, but that Mercedes-Benz provided these salt and pepper shakers, and she had no idea why they picked one with a logo from the competition (and yes, I am the type of nerd that asks such questions :). Anyway, it remains a mystery!

In my next post I will visit the latest and newest German final assembly plant of Mercedes-Benz Rastatt, before looking at their truck plant in Wörth. Now, go out, research good and bad plants to improve yours and organize your industry!

PS: Many thanks to Mercedes-Benz for offering tours through their plants to the public!