Abstract: A riser column particularly for use in deep water comprises a central tube connectable by its lower end to a submerged installation, for example a well, and including means permitting the central tube to oscillate relative to the installation, and connected at its upper end to a suspension table associated with a surface support, for example a platform, and bearing support means intermediate its ends at a level below that at which waves are effective, and a plurality of satellite tubes arranged around the central tube, each satellite tube having a bottom part extending from the intermediate support means to the submerged installation and a removable top part extending from the support means to suspension table and releasably connected to the bottom part thereof for withdrawal from the column following disconnection of the column from the installation, for example, in the event of a storm.

Abstract: An electrical connector for effecting connection between groups of submerged electrical contact elements comprises a plug and a base, each provided with electrical contact elements to be connected and which are immersed in an insulating liquid in respective enclosures in the plug and base, one of the enclosures being annular and inwardly limited by an inner protective body and the other of the enclosures being cylindrical and outwardly limited by an outer protective body. The plug and base are connected by sliding the cylindrical enclosure over the surface of the annular enclosure so as to replace the inner protective body by the cylindrical enclosure and to bring the electrical contact elements into alignment.