The MDL WHLS-100 is a portable horizontal lay system designed specifically for the safe and efficient deployment and recovery of subsea umbilicals, risers, and flowlines (SURF).

In contrast to MDL’s other Horizontal Lay System the WHLS-100 features a unique wheel mechanism which ensures secure and low-friction operations at heavier loads while accommodating various diameters.

Operational Specification

Lay spread type
Portable Horizontal Lay System

18.9m x 9.6m x 11.6m (LxBxH)
18.9m x 12.6m x 11.6m (LxBxH) (Work Platform Extended)

Weight (excluding tensioner)

Clearance between davits and work table

Clearance between davits and hang off

Product Handling Requirements

Maximum product tension
100Te (dynamic load)

Product diameter
90mm - 400mm OD

Overboarding chute/radius capacity

Inboard roller capacity

Hydraulic davit beams capacity
90º coverage/5Te manual beam trolleys

Hang-off capacity
100Te SWL

A&R capacity

100Te SWL

Lifting Equipment

All items supplied with integrated lift points and lift rigging.

Optional spares/workshop container can be supplied.

Power Requirements (HLS only)

3 phase, 440V (+earth), 60Hz

140 amp supply

55kW HPU required

Assumed Conditions

Up to 100%

Marine/high salinity

Design temperature
Operational: -10°C to +50°C

Survival: -20°C to +65°C

Additional Information

Modularity: A modular system that is road transportable for economical road/sea transport.

Easily mobilised: Assembled on the quayside and lifted on board in one lift for the HLS, and second lift for the tensioner.

User-friendly: The main HLS structure combines a tensioner frame, a wheel and actuated work table. The system also features a hang-off and davits for buoyancy installation/removal. Pad basket storage located beside the tensioner to provide access for safe and efficient tensioner pad change out when offshore.

Accessible: All operational areas of the HLS are accessible by stairs, walkways and platforms complete with handrails. Sufficient lighting throughout to facilitate 24-hour operations with an integrated power supply.

Versatile: Designed to integrate with MDL range of tensioners up to 162Te line pull.

Project-focused: The wheel allows for low friction deployment and retrival of flexible products.

Safe: E-stops mounted at each end of the HLS base frame allowing for safe control of operations.

Optional Extras: As each project has different requirements, the following optional extras can be supplied with the HLS:

  • 2x5Te SWL hydraulic davit arms, complete with 90-degree pivot to aid jewellery handing.
  • Integrated pull-through 10Te SWL winch.

WHLS 100 WHLS 100 side