Patent EA-003339-B1 (EA)
Title: Method for producing on a barge or work site an assembly of two metal tubes of a sea line and insulating the assembly zone and adapted tubes therefor
Inventor: ROGER PIERRE
IPC: F16L59/18
Filed: 2000-08-10
Abstract: 1. A method for producing on a barge or a work site an assembly of two metal tubes of a sea line and insulating the assembly zone by means of applying an external heat-insulating coat impermeable to water, resistant to an external pressure and obtained by hardening the material applied on said tubes, according to which metal tubes (T1, T2) are used capable of being mechanically assembled in a predetermined final receive positions, producing on the assembling ends of the tubes, before they are assembled, individual insulating and sealing coats (R1, R2) shaped and dimensioned so that in said predetermined final relative positions the coats are uninterrupted or almost uninterrupted; assembling the tubes and filling, if necessary, the possible residual gap (i) between the coats with an adhesive or sealant. 2. The method according to claim 1, characterized in that the coats are applied so as to conform surfaces of joint frontal planes and parallel therebetween butt surfaces, perpendicular axes of tubes to be assembled or inclined relative to said axis in either direction. 3. The method according to claim 1 or 2, characterized in that the coats are applied and dimensioned so that they can overlap each other. 4. The method according to claim 3, characterized in that the coats are made of an elastomer material and applied so that to conform respective overlapping surfaces (13, 14) having a sinusoidal or stepped form complementary to each other. 5. The method according to claim 3 or 4, characterized in that a suitable greasing is applied upon the overlapping surfaces of coats to facilitate penetration of one coat into the other in the process of assembling the tubes. 6. The method according to any of claims 3 to 5, characterized in that a temporary protection of the overlapping surfaces of coats (13, 14) is provided using detachable caps (5, 6), inserted into (or put on) tubes to be assembled and removed before assembling said tubes. 7. The method according to any of claims 1 to 6, characterized in that after assembling tubes the assembly zone is enveloped with a heat-shrinkable sleeve (M). 8. Metal tubes for sea lines to carry out the method according to one of claims 1 to 7, characterized in that the tubes are assembled by introduction to a predetermined length and fixation a male tube (T1) and a female tube (T2) therein, before the tubes are assembled their ends are provided with suitable sealed to water, heat-insulating and resistant to an external pressure external coats R1, R2) shaped and dimensioned so that after the tubes are assembled a zero gap or a gap of small thickness is left therebetween. 9. Tubes for sea lines according to claim 8, characterized in that the female end of the connection is determined by a connection element of the female end (1a) integrated into the metal tube (T2) e.x. by screwing, wherein the male end of the connection element is determined by the end of the male tube (T1). 10. Tubes for sea lines according to claim 8 or 9, characterized in that preformed coats (R1, R2) of two tubes to be assembled conform annular frontal surfaces (7, 8), which are plane, parallel, straight and perpendicular relative to the axis of tubes to be assembled or inclined relative to this axis in either direction. 11. Tubes for sea lines according to claim 10, characterized in that the frontal surface (7) of the external coat (R2) of the female tube connection end is arranged substantially in the plane of (E) of the connection element (1) front end, wherein that the frontal surface (8) of the external coat (R1) of the male tube connection end is arranged substantially in the plane (L) of rear limit of the tube introduction zone into the connection element so that after the tubes are assembled opposing frontal surfaces (7, 8) of the external coats had zero gap or a substantially zero gap (i). 12. Tubes for sea lines according to claim 8 or 9, characterized in that the external coats are made of elastomer material, wherein coating of the connection end of one tube to be assembled is determined between this coating and the metal tube on which the coating has been applied, a blind or nonthrough interval (9), opened forward, and the coating of the connection end of the other tube present an annular protrusion (10) which is adapted to penetrate with friction so that the coats determine the overlap surfaces (13, 14). 13. Tubes for sea lines according to claim 12, characterized in that the overlapping surfaces (13, 14), one of them, presents one or more bulges (15), the other surface presents one or more cavities (16) respectively. 14. Metal tubes for sea lines to carry out the method according to one of claims 8 to 13, characterized in that comprising detachable caps (5, 6), inserted into (or put on) tubes to be assembled to protect the joint surfaces (7, 8, 13, 14) of the coats.