Multiflex Mooring Compensator

The Multiflex MC1506, MC1507 and MC1508 Mooring Compensators are dumbbell-shaped shock absorbers manufactured from EPDM rubber. Installed on a correctly sized mooring line, each compensator acts as a flexible mooring suspension to help reduce sudden loading on the line, cleats and other mooring fittings. The three listed models suit rope diameters from 10mm to 20mm, with supplied peak-load figures from 300kg to 426kg.

Product Identification

• Brand: Multiflex
• Models / part numbers: MC1506, MC1507 and MC1508
• Product category: Mooring line compensator
• Alternative description: Mooring line shock absorber
• Structure: Dumbbell shape
• Material: EPDM rubber
• EPDM meaning: Ethylene Propylene Diene Monomer
• Function: Mooring-line suspension and shock absorption
• Rope diameters covered by the listed models: 10-20mm
• Available lengths in this listing: 426mm, 490mm and 565mm
• Supplied peak-load range: 300-426kg
• Resistance: Ozone resistant and weather resistant
• Application: Compatible marine mooring lines within the specified rope-diameter range

What Is a Mooring Compensator Used For?

A mooring compensator is fitted to a mooring line to provide a flexible suspension point between the boat and its mooring.

As the boat moves because of waves, wash, tide or wind, the compensator is designed to flex with changes in line tension. This helps reduce abrupt shock loading transferred through the mooring line to:

• Boat cleats
• Mooring cleats
• Fairleads
• Mooring lines
• Other correctly specified mooring fittings

The compensator does not replace a correctly sized mooring line or properly rated deck hardware. It forms one component within the complete mooring arrangement.

What Is Included?

This listing is for:

• One selected Multiflex MC1506, MC1507 or MC1508 Mooring Compensator

Not included unless expressly stated:

• Mooring line
• Boat cleats
• Dock cleats or rings
• Shackles
• Chain
• Mooring springs
• Fairleads
• Other mooring hardware

Which Models Are Available?

Multiflex MC1506

• Length: 426mm / 16.9in
• Hole diameter: 13mm
• Suitable rope diameter: 10-12mm
• Breaking load / peak load: 300kg peak load

Multiflex MC1507

• Length: 490mm / 19.3in
• Hole diameter: 18mm
• Suitable rope diameter: 14-16mm
• Breaking load / peak load: 350kg peak load

Multiflex MC1508

• Length: 565mm / 22.4in
• Hole diameter: 21mm
• Suitable rope diameter: 18-20mm
• Breaking load / peak load: 426kg peak load

Which Mooring-Line Diameter Is Compatible?

Select the model according to the diameter of the mooring line:

• Use MC1506 with compatible 10-12mm rope
• Use MC1507 with compatible 14-16mm rope
• Use MC1508 with compatible 18-20mm rope

Do not select a compensator solely according to its overall length or peak-load figure. The mooring line must also fit the specified rope-diameter range and hole diameter.

The supplied information does not identify compatibility with rope smaller than 10mm or larger than 20mm for these three models.

How Does the Mooring Compensator Reduce Shock Loading?

The EPDM rubber body is designed to provide controlled flexibility within the mooring line.

This helps absorb part of the movement that would otherwise be transferred directly between the boat and the mooring point. Reducing sudden loading can help limit stress on the line and connected fittings.

The level of movement and shock absorption will depend on:

• Selected compensator model
• Mooring-line diameter
• Installation method
• Number and severity of line movements
• Boat movement
• Mooring geometry
• Condition of the compensator
• Condition and rating of the complete mooring system

Why Is EPDM Rubber Used?

The Multiflex mooring compensators are manufactured from EPDM, or Ethylene Propylene Diene Monomer, rubber.

The supplied product information identifies the material as offering:

• High tensile strength
• High torsion strength
• Ozone resistance
• Weather resistance
• Flexible shock-absorbing performance

These properties make the material suitable for exterior mooring applications where the compensator is exposed to changing loads and weather conditions.

What Does the Peak-Load Figure Mean?

The supplied specifications describe the model ratings as both breaking load and peak load:

• MC1506: 300kg peak load
• MC1507: 350kg peak load
• MC1508: 426kg peak load

No separate safe working load, working-load limit or safety factor is stated in the supplied product information. The peak-load figures should therefore not be presented as certified safe working loads.

The complete mooring arrangement must be selected according to the boat, berth, expected conditions and the ratings of all lines, cleats, fittings and other components.

Can These Compensators Be Used for Lifting?

The supplied product information identifies the MC1506, MC1507 and MC1508 as mooring-line compensators.

No lifting certification, lifting application or lifting working-load limit is provided. They should therefore not be listed or represented as lifting devices.

How Should the Correct Model Be Selected?

Select the Multiflex mooring compensator by checking:

• Mooring-line diameter
• Compensator hole diameter
• Required compensator length
• Supplied peak-load figure
• Boat size and movement
• Mooring location
• Expected wind, tide, wash and wave conditions
• Rating of the mooring line
• Rating of the cleats and other fittings
• Available installation space

Where the boat or mooring arrangement is subject to substantial dynamic loading, model selection should be confirmed by a competent marine installer or mooring-equipment specialist.

Construction and Design

• Dumbbell-shaped rubber structure
• Manufactured from EPDM rubber
• Designed to form a flexible suspension within a mooring line
• Designed to improve shock absorption
• High tensile strength
• High torsion strength
• Ozone-resistant material
• Weather-resistant material
• Available in model-specific lengths and hole diameters
• Suitable for correctly sized marine mooring lines
• Intended to reduce sudden loading on mooring lines and fittings
• Straightforward mechanical design with no moving metal components identified

Installation and Safety

Before fitting a Multiflex mooring compensator:

• Confirm that the selected model matches the mooring-line diameter
• Check that the rope can be fitted through the specified hole diameter
• Follow the current Multiflex fitting instructions
• Fit the compensator securely within the mooring-line arrangement
• Do not use a model with rope outside its specified diameter range
• Ensure the line remains correctly attached to the boat and mooring point
• Position the line to minimise chafe against sharp edges
• Confirm that the compensator cannot contact damaging surfaces during movement
• Check that the mooring line, cleats and fittings are correctly rated
• Do not treat the stated peak load as a safe working load
• Do not use the compensator as lifting equipment
• Inspect the compensator regularly for cuts, cracking, deformation or material damage
• Inspect the mooring line for wear, flattening, glazing or broken fibres
• Replace damaged or deteriorated mooring components before further use
• Recheck the complete mooring arrangement after strong winds, heavy wash or abnormal loading

Mooring systems are safety-critical. Selection and installation should account for the vessel, berth, local conditions and the rating of every component in the complete mooring arrangement.

Key Features

• Multiflex EPDM mooring-line compensators
• Models MC1506, MC1507 and MC1508
• Designed to improve shock absorption on mooring lines
• Helps reduce sudden loading on lines and fittings
• Dumbbell-shaped rubber construction
• Manufactured from Ethylene Propylene Diene Monomer rubber
• High tensile strength
• High torsion strength
• Ozone resistant
• Weather resistant
• Suitable for compatible 10-20mm mooring lines
• MC1506 suits 10-12mm rope
• MC1507 suits 14-16mm rope
• MC1508 suits 18-20mm rope
• Available in 426mm, 490mm and 565mm lengths
• Hole diameters of 13mm, 18mm and 21mm
• Supplied peak-load figures from 300kg to 426kg
• No safe working load or lifting certification stated
• Mooring line and installation hardware supplied separately unless expressly stated