Customer story

How Stirmot makes stronger, yet lighter agricultural machines with Strenx® steel

Meet the Big Bull, the state-of-the-art agricultural machine that can do two jobs at once: collect cuttings and bale them too. With a working width of 13.8 meters, it is the widest windrower in the world today. Yet, it can also be folded up for easier transportation. For agricultural contractors, the machine delivers improved efficiency and reduced costs.

Stirmot is located in Medina de Rioseco, a small community 40 kilometers northwest of Valladolid in central Spain. Huge fields cover the landscape and the agricultural industry dominates the region.

Stirmot is no exception. The company, owned by brothers Diego and Victor José Arce Garcia, started manufacturing windrowers in 2014. Today, it sells around 50 machines every year and has customers in the USA, Spain, France and Denmark. With around ten employees, Stirmot is still a small company, but the products are unique in the market. Its bestseller – Big Bull – was launched in 2020 and is the widest windrower in the world today.

“What makes it unique is that it is directly coupled to a baler. So, with a single tractor and just one operator you can do two jobs at the same time. The windrower collects all the cut product and feeds it directly to the baler, helping contractors save both time and fuel,” says Diego Arce Garcia.

"For us, innovation is about surpassing ourselves and constantly trying to make even better machines for our customers. Our collaboration with SSAB means a lot for our product development.”

Diego Arce Garcia, Stirmot

SSAB's Strenx® 700MC steel is used in all of the machine’s structural parts and makes up approximately 90 per cent of all its total steel content.

“By using Strenx, we have been able to design windrowers that are stronger, lighter and more durable. Thanks to the high yield strength of the steel, we avoid fractures and fatigue and significantly extend the machine’s service life,” says Diego Arce Garcia.

While the previous model had a maximum working width of 11 meters, Big Bull can offer up to 13.8 meters. A unique folding system makes it possible to contract the machine during transportation.

“One of the big benefits of this is that no matter the machine’s working width, we never need to exceed the legal four-meter limit to be able to travel on the road,” says Diego Arce Garcia.

Stirmot has been collaborating with SSAB since 2018, and its expertise and advice have helped Stirmot reach its ambitions.

"For us, innovation is about surpassing ourselves and constantly trying to make even better machines for our customers. Our collaboration with SSAB means a lot for our product development. We are a small company and thanks to their expertise and technical support, we have solved the challenges we have had,” says Diego Arce Garcia.

In total, a Big Bull consists of 150 different steel components. They are manufactured at the Hardox® Wearparts center Cortes Metalurgcos Oviedo in Valladolid and then delivered to Stirmot's workshop in Medina de Rioseco. Some minor welding work, painting and assembly are then carried out.

Stirmot has been a member of SSAB’s My Inner Strenx® customer program since 2020. To date, two of its products – Ibero 906 and Big Bull – are certified, but Diego Arce Garcia's goal is to have all the company’s machines covered.

“Being a member of My Inner Strenx greatly benefits us. It means my clients have more confidence in our products,” he says.

One of Stirmot's customers is located in neighboring Castromocho. Here, Juan Carlos Atienza and his cousins run the family business Hermanos Atienza. In a total area of 800 hectares, they grow cereals, sunflowers, alfalfa and hay.

The company bought a Big Bull about three years ago – an investment that has already paid off. "With this windrower, we save both time and fuel. Margins in agriculture are tight, so anything that can help us be more efficient is important. Thanks to its flexible construction, we also get a clean swath, which is a big advantage," says Juan Carlos Atienza.

In 2024, Stirmot will present two new models at the FIMA fair. In the longer term, the company plans to broaden its product portfolio with other machines within the agricultural segment.

“SSAB is a leading company in the development of high-yield steels. We hope to continue maintaining the same close collaboration for the future development of our machines,” says Diego Arce Garcia.

About Stirmot

  • Manufacturer of agricultural machines based in Medina de Rioseco close to Valladolid, Spain.
  • Its production of windrowers started in 2014, and today, the company has approximately ten employees.
  • Stirmot’s windrowers are made using Strenx® 700 MC steel.
  • The company has been a member of the My Inner Strenx® customer program since 2020.

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