In an email to his customer in Iran, the 31-year-old man wrote that the producers of the two valves at the centre of the case were not aware of where they were going to be sent.
The court in Lund, southern Sweden, therefore ruled that he had knowingly sent the technology to Iran, which faces several trade restrictions due to concerns from the international community that the country is planning to develop a nuclear arsenal.
The man does not face jail time, as the court issued a suspended sentence because he has no previous criminal record, nor was he deemed likely to re-offend.
Swedish customs officials discovered the shipment in 2011. It was then on its way to Dubai, allegedly to throw off the scent of its real destination.
Analysts say that the non-corrosive valves can be used in the oil and gas industry, but that the equipment is of such high quality that it is unlikely they would be used for anything but uranium enrichment.
Dual-use refers to technology that can be used in a nuclear programme even though it ordinarily employed in other industries.