GB2134868A

GB2134868A - Submarine cable laying apparatus

Info

Publication number: GB2134868A
Application number: GB08235371A
Authority: GB
Inventors: Kenneth George Pretty
Original assignee: Prysmian Cables and Systems Ltd
Current assignee: Prysmian Cables and Systems Ltd
Priority date: 1982-12-11
Filing date: 1982-12-11
Publication date: 1984-08-22
Also published as: IT1168979B; FR2537796A1; BR8306925A; DK558983D0; ES528235A0; IT8324084A0; DK558983A; SE8306568D0; ES8503897A1; NO834545L; SE8306568L; AU2217083A

Abstract

A modular cable laying apparatus for erecting upon the deck of a barge or other vessel, comprises a plurality of drum stands 10 for placing one-behind- another in a fore and aft line on the deck, and two carriages e.g. 16, one either side of the line of drum stands, for moving along the line of drum stands and capable of lifting each drum 12 in turn to enable rotation of that drum about its axis, one carriage including a drive motor for rotating the drum to pay off its cable. The drum stands, carriages and laying pulley system 20 may be stored and transported in heavy duty containers. <IMAGE>

Description

SPECIFICATION Submarine cable laying apparatus This invention relates to apparatus for laying electric cable underwater, and in the prefer . ed embodiment is concerned with the laying of relatively short lengths of submarine cable where it is uneconomic to use a cable laying ship, and the length of cable to be laid is longer than can be wound onto a single drum.

Previously, laying has normally taken place from a cable laying barge. Each drum of cable can weigh up to 90 tonnes, and when one full drum length has been laid the barge either has to return to dock to be loaded with another full drum or a crane capable of lifting a full drum has to be available to reposition the drums on the barge, so that cable laying can continue. Both of these operations can be costly.

In accordance with this invention, there is provided a modular cable laying apparatus erected or for erecting upon the deck of a barge or other vessel, comprising a plurality of cable drum stands for placing one-behind-another in a fore and aft line on the deck, and a carriage arrangement for moving along the line of cable drum stands and capable of lifting each drum in turn to enable rotation of that drum about its axis, the carriage arrangement including drive means for rotating the drum to pay off its cable.

A particular advantage of the invention is that the apparatus may be stored and transported in heavy duty containers, and set up at the laying site on any conveniently available barge or other vessel of sufficient size and deck area.

An embodiment of this invention wiil now be described by way of example only, with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a schematic plan view of a cable laying apparatus erected on a barge; and Figure 2 is a schematic side view of the same apparatus, showing also the cable drums in position.

The apparatus shown comprises a plurality of stands 10 placed one-behind-another in a fore and aft line on the deck. Each stand supports a cable drum 12, resting by its flanges so that the drum is securely stowed. Along each side of the line of drums, and fixed to the drum stands, there are a pair of runners or rails 14 made up in appropriate sections, one for each drum stand. A carriage arrangement consists of two separate carriages, a drive carriage 16 and an idler carriage 18, running on the rails to either side of the line of drum stands.

The two carriages are to be aligned with each cable drum in turn, and include upper portions provided with spindles 1 6a, 1 8a for engaging in the axial apertures of the drum flanges. The upper portions of the two carriages are firstly capable of movement inwardly towards the cable drum (relative to chassis portions of the respective carriages) for their spindles to engage within the drum. Secondly the upper portions of the two carriages are capable of upward jacking movement to lift the cable drum from its stand 10 so that it is supported on the spindles ready for rotation around its own axis. The drive carriage 1 6 incorporates an hydraulic drive motor for turning the drum to pay-off its cable from its lower side: the cable then passes over a laying pulley system 20 placed on the deck downstream of the line of drum stands.The drive motor is capable of forward and reverse driving and provides inherent braking, but an independent braking system is incorporated in the idler carriage 1 8. The apparatus includes two control positions, one at the drive carriage and another at a remote position on the deck.

The apparatus is arranged to handle a range of drum sizes, by the drive and idler carriages having sufficient ranges of vertical jacking and horizontal movement.

1. A modular cable laying apparatus erected or for erecting upon the deck of a barge or other vessel, comprising a plurality of cable drum stands placed or for placing one-behind-another in a fore and aft line on the deck, and a carriage arrangement for moving along the line of cable drum stands and capable of lifting each drum in turn to enable rotation of that drum about its axis, the carriage arrangement including drive means for rotating the drum to pay off its cable.

2. An apparatus as claimed in claim 1, in which the carriage arrangement comprises two separate carriages for running along either side of the line of drum stands.

3. An apparatus as claimed in claim 2, in which each carriage comprises an upper portion with means for lifting that upper portion and with means for engaging each drum along its axis to support a drum and enable its rotation when the upper portions of both carriages are engaged with the drum from its opposite side and lifted.

4. An apparatus as claimed in claim 3, in which the drum-engaging means of the two carriages comprises spindles for engaging within central apertures in respective flanges of a drum.

5. An apparatus as claimed in claim 4, further comprising means in each carriage for moving its upper portion axially of a drum to engage its spindle with the drum.

6. An apparatus as claimed in any one of claims 2 to 5, in which said drive means comprises a motor incorporated in one said carriage and providing inherent braking.

7. An apparatus as claimed in claim 6, in which an independent braking system is incorporated in the other carriage.

8. An apparatus as claimed in any one of claims 2 to 8, in which each carriage runs on a pair of runners or rails.

9. An apparatus as claimed in claim 8, in which the runners or rails are made up of sections, one section for each drum stand and fixed thereto.

10. An apparatus as claimed in any preceding

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Submarine cable laying apparatus This invention relates to apparatus for laying electric cable underwater, and in the prefer . ed embodiment is concerned with the laying of relatively short lengths of submarine cable where it is uneconomic to use a cable laying ship, and the length of cable to be laid is longer than can be wound onto a single drum. Previously, laying has normally taken place from a cable laying barge. Each drum of cable can weigh up to 90 tonnes, and when one full drum length has been laid the barge either has to return to dock to be loaded with another full drum or a crane capable of lifting a full drum has to be available to reposition the drums on the barge, so that cable laying can continue. Both of these operations can be costly. In accordance with this invention, there is provided a modular cable laying apparatus erected or for erecting upon the deck of a barge or other vessel, comprising a plurality of cable drum stands for placing one-behind-another in a fore and aft line on the deck, and a carriage arrangement for moving along the line of cable drum stands and capable of lifting each drum in turn to enable rotation of that drum about its axis, the carriage arrangement including drive means for rotating the drum to pay off its cable. A particular advantage of the invention is that the apparatus may be stored and transported in heavy duty containers, and set up at the laying site on any conveniently available barge or other vessel of sufficient size and deck area. An embodiment of this invention wiil now be described by way of example only, with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a schematic plan view of a cable laying apparatus erected on a barge; and Figure 2 is a schematic side view of the same apparatus, showing also the cable drums in position. The apparatus shown comprises a plurality of stands 10 placed one-behind-another in a fore and aft line on the deck. Each stand supports a cable drum 12, resting by its flanges so that the drum is securely stowed. Along each side of the line of drums, and fixed to the drum stands, there are a pair of runners or rails 14 made up in appropriate sections, one for each drum stand. A carriage arrangement consists of two separate carriages, a drive carriage 16 and an idler carriage 18, running on the rails to either side of the line of drum stands. The two carriages are to be aligned with each cable drum in turn, and include upper portions provided with spindles 1 6a, 1 8a for engaging in the axial apertures of the drum flanges. The upper portions of the two carriages are firstly capable of movement inwardly towards the cable drum (relative to chassis portions of the respective carriages) for their spindles to engage within the drum. Secondly the upper portions of the two carriages are capable of upward jacking movement to lift the cable drum from its stand 10 so that it is supported on the spindles ready for rotation around its own axis. The drive carriage 1 6 incorporates an hydraulic drive motor for turning the drum to pay-off its cable from its lower side: the cable then passes over a laying pulley system 20 placed on the deck downstream of the line of drum stands.The drive motor is capable of forward and reverse driving and provides inherent braking, but an independent braking system is incorporated in the idler carriage 1 8. The apparatus includes two control positions, one at the drive carriage and another at a remote position on the deck. The apparatus is arranged to handle a range of drum sizes, by the drive and idler carriages having sufficient ranges of vertical jacking and horizontal movement. CLAIMS

10. An apparatus as claimed in any preceding claim, in which each drum stand comprises a pair of convergingly inclined supports for the two flanges of a drum to rest upon.

11. An apparatus as claimed in any preceding claim, further comprising a modular cable laying pulley system placed or for placing on the deck downstream of the line of drum stands.

12. An apparatus as claimed in any preceding claim, further comprising two controlling means, one positioned or for positioning at the carriage arrangement and the other at a remote position on the deck.

1 3. A modular cable laying apparatus substantially as herein described with reference to the accompanying drawings.

14. A modular cable laying apparatus as claimed in any preceding claim, disposed in containers for storing or transport.