The founder – Reidar Frölich Braathen – started “Oslo Sveisebedrift” (OSO) in Oslo in 1932, as one of the first welding shops in Norway. Reidar was both a blacksmith and a lieutenant in the air force and among the first in the country that mastered both electric – and autogenous welding. With minimal resources he created the first welded water heater in Norway. Thanks to his continuous innovation and dedication Reidar employed 100 people by 1940. His 50 years of experience became the foundation of OSO Hotwater – a Norwegian industrial adventure.