SEAT Components

SEAT has a 100% stake in SEAT Components, a member company of the Volkswagen Group, and which produces gearboxes for SEAT, Volkswagen, Audi and Skoda on its site at El Prat De Llobregat (Barcelona). The company is one of five transmission manufacturing plants in the world owned by the Volkswagen Group, alongside Kassel (Germany), Córdoba (Argentina), Shanghai (China) and Mladá Boleslav (Czech Republic).

The SEAT Components site, located close to Barcelona airport, covers an area of 155,000m², of which 85,765m² are workshops, which have a production capacity of 3,200 gearboxes, in a complete process from casting to assembly and quality control, providing work for an overall number of 1,000 people including direct and indirect employment. Since opening in 1979, the factory has achieved well-earned recognition for its efficiency. Amongst other forms of recognition, the factory received the Volkswagen Excellence Award, a business excellence prize handed out by the Volkswagen Group in recognition of the company’s high-quality production process and product.

Gearboxes are one of the most complicated parts in a car and their construction is a highly specialised task. The SEAT Components plant carries out and checks all the processes that enable aluminium ingots and pieces of rough steel to be made into precision mechanisms. Gearboxes are designed to withstand tough operating conditions and consequently all components (casing, gears, shafts, synchronisers and axle box) undergo exhaustive tests meaning that customers receive 100% reliable products.

The manufacturing process of the aluminium parts begins after reception of the raw material in the shape of aluminium ingots which are used for the box and casing. After being melted down in the furnaces it reaches gigantic injectors, where pressure injection gives it the required shape. At the foundry the processes of blasting and X-ray monitoring are also carried out so as to guarantee process quality. Finishing touches are given to the parts by machining the contact faces, as well as the drilling and threading necessary for final assembly.

The gears, shafts, synchronisers and other components inside the box arrive at SEAT Components as pieces of rough steel. The mechanisation process, which is fully automatic, then begins. Over several stages, this process converts a piece of metal into a perfect gear. Specialised employees directly monitor this process, using digitally controlled machines to produce each of the parts. The primary and secondary shafts into which the gears are installed, and the synchronisation parts, are mechanised and corrected over various phases, until they are shaped into the final part.

However, this by itself is not enough. A gear made from the best steel on the market cannot stand up alone to many thousands of kilometres and millions of gear changes. As a result, during the manufacturing process all the gears pass through continuous ovens which, at very high temperatures (close to one thousand degrees), thermally treat each part, ensuring the necessary toughness and resistance. In addition to still being precision parts when they come out of the oven, the gears are also practically unbreakable.

With all the parts prepared and checked, the assembly area carries out the final phase. The automation of this part of the plant is constantly being improved. However, many processes require an expert and skilled workforce. These employees carefully assemble the 200+ components that form a gearbox. The final quality control phase carries out the vital watertightness tests and the operational test benches guarantee the correct working of the box. The manufacturing process has come to an end.


Key figures
Annual production: 559,309 gearboxes
Production capacity: 3,200 gearboxes
Customers: Volkswagen, Audi, SEAT and Skoda
Surface area: 155,000 m² facility, of which 85,765 m² workshops
Workforce: 1,049 employees