Retzlaff - Ingenieurbüro für Schweiß-und Schneidtechnik - maritime Technik
RETZLAFF - Engineering office
Protection of maritime critical infrastructure with ROV and with special technologies - Innovative underwater-welding- and underwater-cutting-technologies

We are an experienced engineering office offering practice-oriented approaches to develop innovative solutions for welding and cutting of individual parts and assemblies. Therefore, we check the materials and design documents for their welding suitability - before starting production - and recommend the best welding or cutting process and the required equipment technology.

Our main business areas are:

  • Maritime infrastructure-ROV-surveillance
  • Research and development projects of innovative ideas and technologies
  • Underwater welding and underwater cutting technologies
  • Underwater inspections (NDT)
  • Offshore oil and gas pipeline platforms and offshore wind turbines
  • Metal and steel construction
  • International project management


Reference object 2020 :

Lindö Port of Odense / Denmark

Züblin A/S – Dk

Underwater Welding

Work order:
Anchor heads : S355J2 ,   sheet thickness :     50 – 100 mm
Sheet piles AZ 38-700N, S430 GP, sheet thickness : 16 mm

Cooperation Partner:
Nordseetaucher GmbH ( Northsea-Diver)

First work samples underwater welded  with pWPS and VT, MT and Break-Tests: no mistakes
Then with WPS underwater welded and  Underwater-VT with our test-diver: no mistakes

Rückblick 2020 - Phoenix Nautica 20Rückblick 2020 - UW-ZfP-Taucher im Einsatz

On the basis of your inquiries with construction documents or sketches, you will receive offers for projects in Germany and abroad:

  • Advice and support for research and development projects for innovative technologies
  • Support with certifications
  • Training and further education or personal qualifications 
  • Project management

Our main business areas:

  • Offshore oil and gas pipeline platforms and offshore wind turbines
  • Underwater welding and underwater cutting technology,
  • ROV/AUV-Production in cooperation with Framwork Robotics GmbH-Rostock-Germany
  • ROV/AUV-inspections, monitoring and underwater NDT
  • Steel hydraulics construction
Quelle : Framework Robotics GmbH, Rostock

Image Source: Framework Robotics GmbH, Rostock

Funding programs

The funding programs are only for German companies!

New welding process for the underwater repair of steel structures

The new underwater welding process is called: DUW-FSW and means: Deep Under Water Friction Stir Welding in water depths of 20m to at least 50m.

Possible without divers!
Find out more in our presentation, which you can download here.




Retzlaff – engineering office for innovative welding and cutting technology – maritime technology

Dipl.-Ing.(FH) / IWE Gunnar Retzlaff

Hermann-Schmidt-Str. 19
D- 99094 Erfurt

Mobile: +49(0)173 / 60 61 447


Postal address:



D-99094 Erfurt