The MDL HLS-400 is a portable horizontal lay system for the deployment and recovery of subsea umbilicals, risers and flowlines (SURF).

The system allows for safe and efficient deployment of product from on-deck reel drive systems and carousels.

Operational Specification

Lay spread type
Portable Horizontal Lay System


20.4m x 6.8m x 10.0m (LxBxH)

With moonpool open

20.4m x 6.8m x 10.0m (LxBxH)

Weight (excl. tensioner)


Work platform deck area
30m ²

Work platform deck capacity

1Te/m ²

Clearance between overboarding chute and hang-off beam

Product Handling Requirements

Maximum product tension
75Te (dynamic load)

Product diameter
50mm - 600mm OD

Entry chute radius

Overboarding chute radius/capacity
4.0m (options available)

Hang-off beam capacity

Lifting Equipment

All items supplied with integrated lift points and swivel lift eyes.

System suitable for onshore lifts in accordance with DNV standards.

If davit arms are supplied these will be provided with manual 5Te chain hoists on trolleys.

Power Requirements (HLS only)

3 phase, 440V (+earth)

60Hz 140 amp supply

36kW 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: Hydraulically operated moonpool doors and hang off beam. Padeyes to aid product handling, strategically placed around the firing line. 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.

Versatility: Designed to integrate the full suite of MDL tensioners for the full range of product diameters. The high and low tension chutes pivot to allow for diameter changes. This provides a consistent product transition into and out of the tensioner with project-driven diameter changes.

Project Focused: The high tension chute is fitted with a water lubrication system. The hang off beams have two integrated 10Te SWL swivel D links for tailing operations.

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:

  • Tensioners are available in optional sizes.
  • Overboarding Chutes are available in optional sizes.
  • 2x2Te SWL hydraulic davit arms, complete with 180 degree pivot to aid jewellery handling.
  • Samson Post with sheaves for direction change for lowering and recovery ends via an A&R winch system.
  • Integrated pull-through 10Te SWL winch.
  • Dedicated 3.75m radius deck deflector with firing line adjustment of 3.2m via hydraulic cylinder system.
MDL HLS400 01 MDL HLS400 02 HI