Patent EA-001073-B1 (EA)
Title: Apparatus for amorphous bonding of tubulars
Inventor: PIETRAS BERND-GEORG
IPC: B23K9/00
Filed: 1998-08-19
Abstract: 1. An apparatus for amorphous bonding the ends of tubulars (110, 111) which are in substantial axial alignment and surrounded by shield gas, said apparatus comprising a jacket (2, 113, 114) which in use is placed around the adjacent tubular ends, said jacket (2, 113, 114) having an inner skin (7, 117) which, in use, defines a sealed inner fluid space (11, 121) containing a heating element (1, 129) and shield gas, and an outer skin (8, 118) which surrounds the inner skin (7, 117) such that in use a sealed outer fluid space (9, 119) is defined between said inner and outer skin (7, 117, 9, 119). 2. An apparatus as claimed in claim 1, wherein said jacket is formed by two parts (113, 114) which are slidably mounted on a support frame (102) and which can be urged together to form said jacket. 3. An apparatus as claimed in claim 1, wherein the inner skin (7, 117) is provided with fluid communication means (10, 153) which allow in use fluid to flow in a controlled manner from the inner fluid space (11, 121) into the outer fluid space (9, 119) or vice versa. 4. An apparatus as claimed in claim 1, including means (131, 130, 128) to introduce shield gas into the inner fluid space (121) and means to introduce water into the outer fluid space (119) and wherein the fluid communication means comprises a conduit (153) which, in use, can convey shield gas to within said outer fluid space (119) at a selected depth below the water level in the outer fluid space. 5. An apparatus as claimed in any of claims 1-4, characterised in that it includes a sensor (124) operative, in use, to delay the process, providing amorphous bonding of said tubulars (110, 111) if there is insufficient water or other fluid in the outer fluid space (119). 6. An apparatus as claimed in claim 1 comprising an inlet pipe (6) for introducing shield gas into the outer fluid space (9), an orifice (10) in the inner skin (7) for allowing the shield gas to flow from the outer fluid space (9) into the inner fluid space (11) and an outlet pipe (12) for allowing the shield gas out of the inner fluid space (11). 7. An apparatus as claimed in claim 1 or 6, further comprising pressure control means which in use control the pressure in the inner and outer fluid spaces (11, 9) such that the pressure in the inner fluid space (11) is higher than the ambient pressure and the pressure in the outer fluid space (9) is higher than in the inner fluid space (11). 8. An apparatus as claimed in claim 2, wherein at least two clamps (104, 105, 106, 107) are mounted on said support frame (102), one of said clamps (104) being adapted to grip a lower tubular (110) and the other of said clamps (106) being adapted to grip an upper tubular (111), and means (108, 109) are provided for displacing one of said clamps (106) relative to the other (104) so that said tubulars (110, 111) can be urged towards one another. 9. An apparatus as claimed in claim 8, further comprising a packer (142) which in use is inserted into the interior of the tubular ends that are bonded by the apparatus, which packer comprises an elongate mandrel (143) having a resilient packer element (144, 145) adjacent each end thereof, means (151) to enable a shield gas to be introduced into an end of said elongate mandrel (143) and to leave said elongate mandrel (143) between said resilient packer elements (144,145), and means (149) to enable water to be introduced into said end of said elongate mandrel (143) and to leave said elongate mandrel (143) between said resilient packer elements (144, 145).