Seaeye Launch & Recovery Systems
(LARS) - Crane Based Systems
 

Seaeye LARS - Crane, winch and HPU on a gravity base.

Seaeye ROV systems are offered with the option of a Launch and Recovery System (LARS). This will include a skid-mounted, integrated winch, power pack, and marine crane or 'A' frame. This section describes the crane option that is illustrated above launching a Lynx ROV in a Type 5 winch and slip ring TMS.

1. DESCRIPTION

The Launch and Recovery System (LARS) comprises:

• Water filled 'Gravity Base' skid with fill and drain points
  
• Protection frame
  
• Lifting slings and spreader bar
  
• Articulated marine crane,
  
• Umbilical winch with level wind
  
• Electro hydraulic power pack (HPU)
  
• Umbilical sheave
  
• Lock latch assembly with hand pump or remote hydraulic release mechanism
  
• Rotary and Stationary Junction Boxes
  
• Slip Ring

The system is designed and DNV approved, to launch and recover an ROV and TMS weighing up to 1350 Kg and accommodate a dynamic amplification factor of 3.0.

As an option the LARS can be provided certified for "Zone 2 " operations.

The articulated crane at full extension with the TMS latched

The system is designed for 1500 metres depth of operation with a winch capacity sized to accommodate 1600 metres of 31mm diameter Seaeye armoured lift umbilical. The base is designed to provide a gravity base support for use on fixed platforms, however it must be noted that there are two methods of operation.

The first method is provide that the crane slew mechanism is limited in travel to prevent the structure tipping to port or starboard to maintain stability. Alternatively bolt-on outriggers can be fitted to the base to provide greater stability in full slew operation. For operations from vessels it may be preferred that the base be fastened to the deck using sacrificial bolted plates.

During initial deployment and final recovery, the ROV and TMS will be latched using the lock latch mechanism with the weight taken on chains shackled to the 1 metre diameter umbilical sheave. This allows the umbilical to be slackened off whilst the crane is being boomed in or out. To lower the ROV the weight is taken up on the armoured lift umbilical allowing the latch to be released and the ROV and TMS to be lowered to depth.

All hydraulic power requirements for the Articulated Crane and Winch are provided by the Electro Hydraulic Power Pack (HPU).

For transportation and shipping, the Articulated Crane folds and is locked in the stow position.

LARS stowed for transportation

Motor Control provides fail safe lever control with variable speed in both directions and operation of the hydraulic brake mechanism.

The Winch Brake is both Primary and Fail Safe using an over centre valve.

The winch drum is driven by an axial piston hydraulic motor through a totally enclosed planetary gear reducer. The gear reducer is mounted at right angles to the drum barrel at one end. A totally enclosed spring set hydraulic pressure released multi disc brake is located between the hydraulic drive motor and gear reducer.

The umbilical level wind mechanism comprises a Diamond Bar driving umbilical Guide Rollers via a chain drive with reduction from the main drum.

ELECTRO HYDRAULIC POWER PACK (HPU)

The HPU is integrated with the LARS system and is provided with dual hydraulic pumps capable of supplying all of the hydraulic requirements for operation of the winch and articulated marine crane.

SPECIFICATIONS MAY CHANGE WITHOUT PRIOR NOTICE