The Sulzer BBC steam machine has been supplying electricity to the DMC plant in Mulhouse for nearly 50 years. Invented at the beginning of the 20th century, this perfectly honed piece of machinery exemplified the power of a company and the city of Mulhouse. Today, it has become the symbol of a flourishing industry of the past.
Vue d'artiste de l'usine DMCElectropolis Museum
In Mulhouse, the huge DMC sewing and embroidery thread factory (Dollfus-Mieg and Company) was gradually electrified from 1878.
At the turn of 1900, the management decided to build a power plant to produce its own alternating current. It was placed between the 2 chimneys.
Le bâtiment de la centraleElectropolis Museum
The new plant was opened in 1902.
Vue d'ensemble de la centrale DMCElectropolis Museum
It was specially built for this machine, which powered the plant with electricity until 1946.
Section allemande de la "Galerie des Machines" à l'Exposition Universelle de 1900Electropolis Museum
It's said that this machine was used to light the Exposition Universelle of 1900. However, DMC's machine is very different from those that were on display in Paris and bears the date of 1901 in large characters inscribed in the cast iron!
Plan des fondations dressé par les établissements SulzerElectropolis Museum
The Sulzer steam engine and the BBC alternator (Brown, Boveri and Company) represent both the culmination of a technology and its swan song, as piston machines were then abandoned in favor of steam turbines.
Turbine à vapeur de la centrale électrique DMCElectropolis Museum
DMC invested in new steam turbines as early as 1909 and 1911. They were much less bulky than the piston machine and the power they produced was far greater.
Vue d'ensemble de l'alternateurElectropolis Museum
However, the Sulzer machine remained in operation because it was designed to last indefinitely if properly maintained. Essential parts could even be replaced without the need to stop the machine.
Moteurs électriques sur les machines du retordage de DMC, vers 1930Electropolis Museum
When DMC was set up, they bought roughly a hundred electric motors. As early as 1904, many of the steam engines began to disappear from the workshops, replaced by an electric motor on each machine.
La centrale DMC au début du démontageElectropolis Museum
The plant was the energy-pumping heart of the factory. Working there was a real privilege for handpicked workers. The cast iron pilasters and classical cornices resembled those of a temple.
The entrance to the plant was so strictly off limits that almost no DMC personnel had ever seen the inside.
Supports des câbles à la sortie de l'alternateurElectropolis Museum
Next to the alternator's large wheel, the porcelain insulating supports carried the 400-volt, 3-phase cables to a transformer that then supplied the entire plant with electricity.
Vue aérienne de l'usine DMCElectropolis Museum
At the beginning of the 20th century, the DMC factory was like a city within a city, employing up to 5,000 workers.
Managers could judge the quality of the operators' work from a distance based on how much smoke they were able to see.
At DMC, each machine is inventoried and labeled. Even with a weight of almost 190 tons, the generator has its own unique inventory number.
Locomotive du réseau d'usine DMC, vers 1930Electropolis Museum
Four small locomotives transported the heavy equipment and coal from the boilers via the narrow lanes that run along the arteries of the factory.
Train de matériel sur le réseau d'usine DMC, vers 1930Electropolis Museum
During winter, unloading the carts, each of which contained about 1.65 tons of coal, was a particularly painful exercise because it was necessary to continually pass from the scorching heat of the boiler (up to 104°F) to the cold outside.
Chaudières du blanchiment de DMCElectropolis Museum
Normally, preheating the boilers started at 4:30 or 5:00 in the morning, to provide the machine with 12 bars of steam pressure and have it ready to put it into operation well before the factory started at 7:00 a.m. During particularly cold winters, preheating could begin as early as midnight. Each operator shoveled up to almost 7 tons of coal a day.
Le régulateurElectropolis Museum
Every morning, the manager passed his finger along a part of the machine to check the cleanliness. The workers said that things were so clean that you could have eaten off the floor.
Vue de la centrale vers 1930Electropolis Museum
This image is one of the few photographs showing the plant in operation. It's also the only one to show a worker. Some employees worked at the plant for over 40 years—sometimes until the age of 72.
Huileur goutte à goutte devant l'alternateurElectropolis Museum
To lubricate the machine, there were 48 drip-feed oilers, 4 sealing strips, 5 oil pumps, and 315 points to be greased manually.
A worker constantly went around the grease points and filled the oilers. Oil consumption was over 26 gallons per week.
La centrale DMC vers 1930Electropolis Museum
According to some witnesses, the sound of the machine was deafening. Yet the mechanics of the steam engine were almost silent. It was the alternator's intense electromagnetic fields that produced a purr similar to that of today's power plants.
Vue d'ensemble de la centrale, vers 1930Electropolis Museum
The machine was cleaned every Saturday morning during the factory downtime from 11:00 a.m. to 1:00 p.m. by a team of 10 workers equipped with rags.
Le tachymètre, état d'origine chez DMCElectropolis Museum
The tachometer measured the rotational speed of the alternator. This speed of 75 rpm had to be extremely accurate to obtain AC power at 45 Hertz.
In 1923, it rose to 83 revolutions per minute to increase to 50 Hertz, which allowed the current produced during the lunch period to be sold on the public network.
Vue d'ensemble à vol d'oiseau de l'usine DMCElectropolis Museum
After the liberation of Mulhouse at the end of 1944, the DMC power plant temporarily supplied electricity to part of the city. This was its last significant period of operation before becoming a backup plant in 1946.
Vue d'ensemble de la centrale avant démontage du groupe électrogèneElectropolis Museum
From 1953 to 1978, the Sulzer-BBC machine became a "Sleeping Beauty." After its decommission at DMC, it was no longer maintained and patiently waited to be rediscovered.
Next: The Sulzer-BBC machine and the Electropolis Museum, episode 2
Crédits :
© Henri COLLOT
Remerciements :
- à Damien Kuntz, responsable du service scientifique au Musée Electropolis.
- au Pôle valorisation du patrimoine industriel du groupe EDF.
