How to manufacture five million tires every year

Between the Plaza Mayor of Valladolid and the Bibendum roundabout there are 4.1 kilometers and thousands of distance lives. Exactly those who work, have worked or work at the Michelin factory in the city of Pisuerga who, Like Renaultis one of the great engines of the city.

The union with the city is so great that “in fact, the idea of ​​calling Bibendum Glorieta at the entrance of the factory left the City Council. We had a generic name of industrial polygon. We wanted to change it and they themselves proposed the name,” they point to us from the company whose doors proudly look its famous Pet in a gigantic size.

And it is that 2,200 workers pass every day (almost 1,700 of them are part of the workforce and another 500 work in maintenance or cleaning, among other functions) that keep the plant to full performance, with three eight -hour shifts that keep alive an annual production of five million tires. The objective is clear: fill the 50 trucks that come out every day.

Valladolid is not one more factory for the company. It is one of the so -called “digital factories” for the high investment that has been made in all types of systems to carry out a controlled production to the extreme.

This investment is manifested in the machinery that gives life to gums for cars, trucks and tractors that are manufactured there but also for the control of the entire assembly line. It is there, exactly, where our visit begins.

A control tower

We could say that the Valladolid machine room is the opposite of what we could imagine. The Castellanoleonese plant moves to the rhythm of two operators that supervise everything that happens locked in an office.

By hand they have two computers with multiple monitorson the wall the screens are multiplied with cameras distributed throughout the facilities, colored notices of all kinds and a volume of numbers, names and information for profane eyes.

Our guide points to a side wall in which we had not repaired given the communicative epilepsy we had in front of us. Simply, lines and bulbs. This worked before and thus still controls the management of the inventory or the situation of the machines in some plants.

Valladolid, they explain to us, have some of the most advanced control and supervision systems and, in fact, have worked to implement some of the solutions in other plants of the company. The intention is clear: all unforeseen must be controlled at the time for the production chain to stop the minimum and essential. From a breakdown to the shortage of a product.

We leave that luck of control tower to put the feet on the mainland. In front we have the compounds that give life to a rubber. They are so simple that they look like a children’s game. Rubber, a metallic ring, the fabric that structures the wheel and the rolling band.

So simple that it seems a lie that we talk about a product capable of resisting the force exerted by a car that rolls more than 100 km/h, a truck that transports tons of merchandise or a tractor that, with the agricultural tires More advanced, it can circulate at 80 km/h.

“In the United States it is legal for a large tractor to circulate at that speed.” What is unthinkable here “creates a problem when thinking about how to face wear. So we have a system so that, from the tractor itself, the tire pressure is increased so that a smaller surface touch the ground when it moves through the asphalt. And, on the contrary, you can lower the pressure to gain trace when it gets into the field,” they explain.

This way of working, without leaving from the tractor cabin, is a solution like the one that They use the pilots in the Dakar Rally That, from inside the car, they put pressure if they want to gain speed on a fast track or remove it if they need to cross a dune since it requires greater contact with the ground to have greater traction capacity.

From the rubber to the road

This is the key to everything. With the hand, our guide holds the tire rubber. “Each rubber has its own mixture and is secret,” they point to us. It is about making the most balanced rubber for each vehicle and moment. Not only is it a matter of offering the best grip, you also have to get the slightest rolling resistance (lower consumption) or less noise. And those concepts are enemies of braking, traction and, of course, performance.

Join those Three pillars In a single tire is the biggest challenge, prioritizing with each type of product one or another game. For example, a Michelin Primacy 5the tire that we have come to know and that is designed for great general performance and good behavior in summer, that a Michelin CrossClimatedesigned to replace the chains in case of Nevada, or a Michelin Pilot Sportfor sports driving.

The heart of each has its own mixture of ingredients (they add up to 200,000 tons of rubber per year). And that mixture enters through a machine that is in charge of flattening and shaping the compound. The mixture is heated, flattened and forms the heart of the tire. That already ironed rubber is painted with brands to facilitate the subsequent process management.

As if it were a very long plasticine without principle or end, the machines are cutting into strips and barrels serve to generate the rounded shape. This is where the metallic ring and textile meshes are inserted in charge of structuring and supporting the vehicle pressures. The heavier, the greater the resistance the mesh should exert, so in the specific models for SUV or electric cars, two meshes are usually included.

Finally, everything is covered with a last layer that will form the rolling band. This is drawn in the process of Vulcanizedat which time the tire enters a gigantic oven inside a mold. After a time that varies depending on the tire (it can go from two to three minutes for one tourism to more than a quarter of an hour if we talk about an agricultural tire) it is already extracted with the desired form.

The tire is finished but still has to be checked. This last process, which in Lasarte is done by hand, in Valladolid is being perfected through machines that use light waves to find possible defects. If this machine located one of them, the rubber comes to the operator to check if we are facing a true defect.

At the moment, we have already entered the “Contact 0”. From here until the tire is put in the wheel of our car no one will touch the rubber. The trip through the hundreds of meters (I thought thousands) of ramps that transport the tires and their subsequent storage is completely machined. Only a few operators handle the tires and take care of stacking them and giving them exit in the trucks.

The warehouse impresses. Mirees where you look you find rubber and the smell of rubber is very strong. Once outside, we appreciate the breeze that runs on a summer day in which a few clouds have given us some truce.

We have in the feeling of leaving our own city, one that flows at a different rate from that of neighboring Valladolid and that, unlike it, lives in a total harmony between machines and people so that nothing stops, nobody hinders a march that must flow without rest.

Photos | Michelin

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