Tube connector for detachably connecting two connector parts for gas-tight connecting of riser tubes to vessels

1. A hollow tube connector for detachable connecting of two connector parts comprising:

a first connector part wherein a first of first and second axial ends of the first connector part is configured to connect to at least one pipeline on a vessel,

a second connector part wherein a first of first and second axial ends of the second connector part is configured to connect to at least one pipeline located on a submerged turret production-buoy,

a clamping device which entirely or partially encloses the second axial ends of the first and second connector parts such that the first and second connector parts are clamped together to form a fluid-tight connection for a hollow tube,

wherein contact surfaces of the second axial ends of the first and second connector parts comprise inner contact surfaces and at least two non-crossing grooves having a middle contact surface between the at least two non-crossing grooves, and a first outer contact surface outside the at least two non-crossing grooves and extending circumferentially around the contact surfaces, the at least two non-crossing grooves located on one of the contact surfaces each having a mirror-imaged groove located on the opposite contact surface providing two pairs of opposite non-crossing groves such that the two pairs of opposite non-crossing grooves and mirror-imaged grooves form at least two encompassing cavities upon contact of the contact surfaces and each including at least one sealing ring configured to be positioned in one or more of the at least two non-crossing grooves and the at least one mirror-imaged grooves prior to sealing connection between the first and second connector parts upon contact of the contact surfaces;

the inner contact surfaces tapering inwardly towards an inner first point of contact between the first connector part and the second connector part, wherein the middle contact surface and the first outer contact surface do not contact each other when the clamping device is tensioned, thus forming an inner pre-tensioned, ring-shaped and abutting contact zone and an outer pre-tensioned, ring-shaped and abutting contact zone inside and outside of the at least two sealing rings respectively, making a fluid-tight connection of the first and second connector parts resistant against internal pressure and strain.

2. The hollow tube connector according to claim 1 , further comprising at least one test channel as an open channel with a first end located in an interface between the two contact surfaces between the at least two encompassing cavities, and a second end located on an outer surface of the hollow tube connector.

3. The hollow tube connector according to claim 2 , wherein the at least one test channel is configured to allow injection of at least one test medium for pressure testing.

4. The hollow tube connector according to claim 1 , including at least one of an outer groove wall and an inner groove wall, each outer groove wall and inner groove wall being associated with one groove of the at least one groove which faces inwards to and out from the center axis of the hollow tube connector respectively, and having an orientation which differs from an axial orientation with respect to the center axis of the hollow tube connector.

5. The hollow tube connector according to claim 4 , wherein the inner groove wall of at least one of the grooves which faces out from the center axis of the hollow tube connector has a part at an angle closest the contact surface which differs more than the angle of a remaining part of the groove wall in relation to the center axis of the hollow tube connector.

6. The hollow tube connector according to claim 1 , wherein the first and second connector parts further comprise outer contact surfaces comprising mating substantially cylindrical and tapered guiding faces on the upper and lower hub respectively, to ease centration.