All required diving work and checks during all Mergor operations are done by OTN (a Strukton company). For the Busan Geoje Fixed Link Tunnel Project OTN deployed their Self Propelled Diving Bell (SPDB) called ‘Aurora’. The SPDB is a state of art fitted and completely revised submarine with an 180dgr dome window and all required navigational equipment on board and can be utilised to depths up to 300m! The SPDB is not only deployed for inspections but for under water activities as well.
Together with the pilot and co-pilot divers can travel in the SPDB and use it as a diving bell or interlock the SPDB to the immersed tunnel element and access the tunnel. The manipulators on the SPDB are also used for cutting steel wires (up to 54mm) and locking of nuts.
With the use of this SPDB and the unique survey system of Geocon tunnel elements can be immersed without access shaft and survey towers!
The use of the SPDB for an immersion project is a first, not only for Strukton Afzinktechnieken – tradename Mergor - but for the complete branch as well.