Streamer connection system

• US 8,348,543 B2
• Filed: 03/23/2009
• Issued: 01/08/2013
• Est. Priority Date: 03/23/2009
• Status: Expired due to Fees

• Current Assignee: DIGICOURSE LLC
• Original Assignee: ION Geophysical Corporation
• Inventors: Olivier, André W.
• Primary Examiner(s): Ferguson, Michael P
• Assistant Examiner(s): WILEY, DANIEL J
• Application Number:
  US12/409,301
• Publication Number:
  US 20100239367A1
• Time in Patent Office: 1,387 Days
• Field of Search: 403/109.1, 403/109.2, 403/109.3, 403/109.5, 403/192, 403/195, 403/321, 403/325, 403/329, 403/353, 403/365, 114/245, 114/243, 114/253, 441/133
• US Class Current: 403/353
• CPC Class Codes: B63B 21/663 Fairings
• CPC Class Codes: G01V 1/201 Constructional details of seismic cables, e.g. streamers integrated optoseismic systems G01V1/226; line connectors in general H01R, transducer mountings in general G10K11/004
• CPC Class Codes: Y10T 403/76 having a cam, wedge, or tapered portion

Abstract

A connection system for connecting external devices to specified locations on a marine seismic streamer. Inner collars having raised bosses are clamped to the cable at specified locations along its length. Each inner collar forms a circular race encircling the cable. An external device is attached to a pair of cuffs in the form of C-shaped cylindrical rings each with a circular inner surface. A gap in the ring interrupts the inner surface. The width of the gap is greater than the diameter of the bosses so that the cuffs may be slid onto the collars when the gaps are aligned with the bosses. The bosses are circumferentially offset when the cable is in its normal operating state to lock the cuff and the external device to the collars. The cuffs and the external device can be installed on or removed from the cable by twisting the cable to align the bosses and sliding the cuffs onto or off of the collars. When installed, the cuffs ride on the races to allow the cable to rotate inside the cuffs.

Claims

1. A connection system for connecting an external device to a location on an underwater cable, the connection system comprising:

a first collar attached around a longitudinally extending underwater cable at a first location, the first collar having an outer cylindrical race encircling the underwater cable and a raised boss on a periphery of the first collar forward of the outer cylindrical race, wherein the raised boss has a rear bearing surface extending circumferentially part of the way around the periphery and perpendicular to the underwater cable, the rear bearing surface defining a forward end of the outer cylindrical race;

a second collar attached around the underwater cable at a second location aft of the first location, the second collar having an outer cylindrical race encircling the underwater cable and a raised boss on a periphery of the second collar forward of the outer cylindrical race, wherein the raised boss has a rear bearing surface extending circumferentially part of the way around the periphery and perpendicular to the underwater cable, the rear bearing surface defining a forward end of the outer cylindrical race;

a first C-shaped cuff including an outer surface having attachment means for attaching an external device to the outer surface, an inner surface defining an inner diameter, and a throat formed by a longitudinal gap between the ends of the C, wherein the gap has a width greater than or equal to a maximum circumferential dimension of the boss on the first collar;

a second C-shaped cuff including an outer surface having attachment means for attaching an external device to the outer surface, an inner surface defining an inner diameter, and a throat formed by a longitudinal gap between the ends of the C, wherein the gap has a width greater than or equal to a maximum circumferential dimension of the boss on the second collar;

wherein in a normal operating state, the first and second collars are inserted into the first and second cuffs, respectively, such that;

the outer cylindrical races of the first and second collars are rotatably engaged with the inner surfaces of the first and second cuffs, respectively, and the rear bearing surfaces of each raised boss are located forward of each cuff; and

one of the first and second raised bosses is circumferentially offset from one of the gaps in the first and second cuffs whenever the other of the first and second raised bosses is circumferentially aligned with the other of the gaps in the first and second cuffs,

whereby removal of the cuffs from the collars by a force acting in the forward direction on the cuffs is prevented.

2. A connection system as in claim 1 wherein the boss on the first collar and the boss on the second collar are made of a deformable material that deforms under thrust loads greater than the thrust loads due to wave action.

3. A connection system as in claim 1 wherein the bosses are triangular-shaped.

4. A connection system as in claim 1 wherein the inner diameters of the C-shaped cuffs are greater than the outside diameters of the races, but less than the outside diameters of the races plus a maximum radial thickness of the bosses.

5. A connection system as in claim 1 wherein the bosses are sacrificial elements having shear pins that yield under thrust loads against the bosses greater than the shear threshold of the shear pins.

6. A connection system as in claim 1 wherein the bosses are each expandable from an unlocking position in which the width of the gap is greater than or equal to the maximum circumferential dimension of the boss to a locking position in which the boss expands to span width of the gap.

7. A connection system as in claim 1 wherein the bosses are spring-loaded pushbuttons.

8. A connection system as in claim 1 wherein the bosses each include two portions circumferentially separable from each other.

9. A connection system as in claim 1, wherein at least one of the first and second collars further includes a raised shoulder on the periphery of the first collar aft of the outer cylindrical race, such that the rear bearing surface of the boss and the raised shoulder define forward and aft ends of the outer cylindrical race, respectively.

10. A connection system for connecting an external device to an underwater cable, the connection system comprising:

a collar attached to a longitudinally extending underwater cable, the collar including an outer cylindrical race encircling the underwater cable and a raised boss on a periphery of the collar forward of the outer cylindrical race, wherein the raised boss has a rear bearing surface extending circumferentially part of the way around the periphery of the collar and perpendicular to the length of the underwater cable, the rear bearing surface defining a forward end of the outer cylindrical race; and

a C-shaped cuff having an outer surface with attachment means for attaching an external device to the outer surface, an inner cylindrical surface engaged with the outer cylindrical race of the collar, and a throat formed by a longitudinal gap between the ends of the C, wherein the gap has a width;

wherein the boss includes two circumferentially separable portions, and the boss is movable between a contracted, unlocked configuration, in which a maximum circumferential dimension of the boss is less than or equal to the width of the gap, and an expanded, locked configuration, in which the maximum circumferential dimension of the boss is greater than the width of the gap.

11. A connection system as in claim 10 wherein the boss is triangular-shaped.

12. A connection system as in claim 10 wherein the boss is a sacrificial element having shear pins that yield under thrust loads against the boss greater than the shear threshold of the shear pins.

13. A connection system as in claim 10 wherein the boss is a spring-loaded pushbutton.

14. A connection system as in claim 10, wherein the collar further includes a raised shoulder on the periphery of the collar aft of the outer cylindrical race, such that the rear bearing surface of the boss and the raised shoulder define forward and aft ends of the outer cylindrical race, respectively.