Claims
- 1. An arrangement for transferring loads by means of one or more hydraulic cylinder-like actuators (19, 26, 40) in order to establish and maintain tension in a riser (1) of the type typically used in offshore petroleum production, where the riser (1) constitutes a connection between the sea bed (2) and an installation (4) on or near the surface of the sea (6), and where the required pressure difference between the pressure side(s) (18, 42) and the depressurised side(s) (17, 46) of the actuator(s) (19, 29, 40) is constituted by a hydrostatic pressure difference, characterised in that the pressure side(s) (18) of the actuator(s) (19, 29) is/are communicatingly connected with the seawater, directly or indirectly, via a pipe connection (22), an opening (28) being located at a considerable depth below the surface of the sea (6), and where the pipe connection (22) is substantially filled with a fluid with a lower density than that of water.
- 2. An arrangement in accordance with claim 1, characterised in that the depressurised side(s) (17) of the actuator(s) (19, 29) is/are communicatingly connected with the atmosphere through an opening (27).
- 3. An arrangement in accordance with claim 1, characterised in that the depressurised side(s) (17, 46) of the actuator(s) (19, 29, 40) is/are closed and under vacuum.
- 4. An arrangement in accordance with claim 1, characterised in that the pipe connection (22) communicates with the seawater via a bell (20).
- 5. An arrangement for transferring loads by means of one or more hydraulic cylinder-like actuators (19, 26, 40) in order to establish and maintain tension in a riser (1) of the type typically used in offshore petroleum production, where the riser (1) constitutes a connection between the sea bed (2) and an installation (4) on or near the surface of the sea (6), and where the pressure sides (42) of the actuators (40) are communicatingly connected with the seawater, directly or indirectly, via an opening (44), where the opening (44) is located at a considerable depth below the surface of the sea (6), characterised in that the depressurised sides (46) of the actuators (40) are communicatingly connected with the atmosphere via a pipe connection (48) and through an opening (27), and where the pipe connection (22) is substantially filled with a fluid with a lower density than that of water.
- 6. An arrangement in accordance with claim 5, characterised in that the depressurised side(s) (46) of the actuator(s) (40) is/are closed and under vacuum.
Priority Claims (1)
Number |
Date |
Country |
Kind |
20012078 |
Apr 2001 |
NO |
|
CROSS REFERENCE TO RELATED APPLICATION
The present application is the U.S. national stage application of International Application PCT/NO02/00153, filed Apr. 23, 2002, which international application was published on Nov. 7, 2002 as International Publication WO 02/088512. The International Application claims priority of Norwegian Patent Application 20012078, filed Apr. 27, 2001.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/NO02/00153 |
|
WO |
00 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO02/08851 |
11/7/2002 |
WO |
A |
US Referenced Citations (4)
Foreign Referenced Citations (2)
Number |
Date |
Country |
302493 |
Mar 1998 |
NO |
308379 |
Sep 2000 |
NO |