Diving and Underwater Technical Works | Services of CNGS Engineering Company

Diving and Underwater Technical Works

The diving and underwater technical works during construction of the fixed offshore platforms, subsea pipelines and offshore terminals are provided by the specialized divisions of the Company.

The main operational facilities for diving and underwater technical work are located in Astrakhan (RF) and in Hazar (Turkmenistan). The Company units are equipped with the required certified diving equipment and capable of simultaneously performing the work using six diving stations.

The team of professional divers has rich work experience, including:

  • diving inspection of pipelines and cable routes prior to installation;
  • diving inspection of offshore fixed platforms and terminals;
  • inspection of laid pipelines using divers, as well as an underwater remotely operated vehicle (ROV);
  • underwater welding and cutting of metal and concrete;
  • removal of jackets of offshore fixed platforms, underwater cutting of piles and anodes;
  • installation of grip couplings for connecting underwater pipelines, execution of pipeline field joints under water;
  • diving support for offshore operations during the construction of offshore fixed platforms, subsea pipelines, offshore terminals;
  • elimination of unallowable free spans of pipelines by means of underwater concreting;
  • installation of risers, spools, bracings, clamps, protection of risers, fenders using a hydraulic tool;
  • underwater concreting of the inter- pile space of the legs of oil-producing platforms;
  • cleaning the platform legs in the splash zone with a URACA high-pressure unit for applying a two-component protective layer;
  • soil development with the help of a pit hydraulic monitor for laying cables with the subsequent installation of cable conduits;
  • diving support when laying the power submarine cable lines and cables for geodynamic and hydrological monitoring systems and installation of sensors. Installation of tight seals in pipe inserts;
  • burying the power submarine cable lines and cables of geodynamic and hydrological monitoring systems using the subsea ST-2 and OTTER-2 trenchers;
  • diving support when driving conductors.