Based on their long and varied experience in new building, conversion and retrofit, Knaack & Jahn Schiffbau GmbH, located in Hamburg and with branches in Bremen, Bremerhaven, Kiel etc., is a reliable and recognized partner with shipyards, shipping companies and private customers both foreign and abroad.Our core competence is in pipeline and plant construction for industry, shipbuilding and building technology. Where piping is concerned, we provide the highest quality and a complete service.