1. GENERAL

1.1. INTRODUCTION

This specification covers the minimum technical requirements for the supplyof a ROV spread to be deployed and operated in order to perform constructionsupport

1.2. SCOPE OF WORK

Typical Pipeline Project scope of work consists of:
* The construction of  pipeline
* The fabrication and installation of Underwater Tap Valves assemblies.
* The crossing of  foreign pipelines
* The trenching of the  pipeline.
 

2. ROV SPREAD SPECIFICATION

2.1. MAIN FEATURES

The ROV shall be an Work Class ROV (scorpio or similar) of a proven type  and of reputable manufacture. It shall have a documented history of satisfactory operational performance in the concerned geographical area.
The vehicle capacities shall be sufficient to perform the tasks definedin the scope of work in the extreme environment conditions.
The main characteristics of the ROV shall be equal or above the followingvalues:
* 75 HP minimum power and thruster able to sustain up to 3 knots surfacecurrent and 2 knots bottom current
* lift capacity 60 kg
It shall be equipped with auto-heading, auto-depth and auto-altitudefunctions.
It shall have a sufficient length of umbilical to provide the requiredoperation radius.

2.2. ROV SYSTEM DESCRIPTION

The main components of ROV system shall include:
* the vehicle.
* the launch and recovery system.
* the umbilical winch.
* the control cabin.
* the workshop cabin.
* the communication system.
* the close circuit television system
* the spares and miscellaneous equipments.

2.3. ROV INSTRUMENTATION

The ROV shall be fitted with the following equipment, but not limitedto:
* high definition sonar system.
* colour cameras system
* B/W sit cameras.
* underwater lighting.
* S-VHS video system including video overlay facilities.
* video printer.
* north-seeking gyrocompass.
* pitch, roll sensors.
* 5F manipulator arm.
* 7F manipulator arm.
* high accuracy bathy-system.
* dual head scanning sonar.
* Dual boom camera system
* pipe/cable tracker system
* transponder/responder USBL beacon
* LBL flowerpot

2.4. INTERFACES WITH POSITIONING

2.4.1. Positioning Systems
ROV shall be positioned using a USBL acoustic positioning system.
ROV support Vessel shall positioned using DGPS systems
Navigation system shall be interfaced with both DGPS and USBL systems
Note:These systems shall be operated by POSITIONING SUBCONTRACTOR

2.4.2. Survey Information
Data from ROV (gyro, ROV bathy system, DHSS, etc...) shall be interfacedto the navigation system using standard RS 232 C interfaces.

2.4.3. Video Overlay
Information including Northing, Easting, Date, Time, KP and Z fromtransponder shall be sent to the Overlay Units of the ROV system.(eitherLiebnitz-Lann 207 LR or another agreed type).

2.5. SURVEY DATA ACQUISITION AND PROCESSING

Positioning and Survey informations will be processed and logged byPOSITIONING SUBCONTRACTOR.