Tugs in Emden

Some steam tugs moored in the industrial port of Emden in the early 1930's.

In the background we have the huge launchways and cranes of Nordseewerke Emden. This wharf was founded on March 11th, 1903 and is currently one of the oldest among the still-existing shipyards in Germany. The company built many ships for Kaiserliche Marine during WW 1 and the Kriegsmarine during WW 2, i.a. 30 U-Boats, as well as for the modern Deutsche Marine, i.a. frigates Emden, Hessen and Bayern (1980-2003).
Today Nordseewerke Emden are known for the co-planning and construction of the submarine classes 206 and 212, the latter representing Germany's most modern submarines, a a highly advanced design of non-nuclear submarine driven by hydrogen fuel cells. Until 2010 the Nordseewerke built or repaired in all 550 vessels.
Any idea on the company the tugs belongs to ? Any help is welcome.