Mooring System and its
Working Principle
Introduction
• Whenever a vessel ceases its voyage, it gets to a terminal and pauses its
propulsion, staying vulnerable to the action of drifts and winds.
• At this point, to be maintained secure, it must remain immobilised,
establishing its place by means of the pieces that make up the mooring
• In this presentation the term mooring refers to the system that secures a
ship to the terminal.
• Ship mooring systems (SSM) traditionally rely on mooring lines to anchor a
ship.
• Nonetheless, with advancement in technology, new mooring systems
(NSM) have been developed using different physical concepts.
An arrangement of mooring maneuvers with a small electrical windlass to
work as a mooring device.
Principles of a good Mooring System
• The mooring system of a ship will constantly have to withstand the
impacts of wind, currents, and surges from passing boats (Remery,
1974).
• Should also be able to withstand the effects of waves and swells
(Bowers,1975).
• Additionally, the system must take into account the slack in the
mooring lines and the vulnerability of the moored ship to the wind,
currents, and wave forces.
• Due to this, the designer may choose and arrange mooring
equipment and fittings on the vessel and along the quayside.
Mooring Equipment
a. Mooring Lines
• The mooring system distributes the forces generated by the ship
along the mooring lines as a starting point.
• The fixed components of the terminal are subjected to these forces.
• It is essential that the mooring line's vertical and horizontal angles be
as little as feasible if either method is to be successful.
• The mooring line with the largest diameter and the shortest length is
the one that will be subjected to the most effort when compared to
the other lines.
b. Mooring Winches
• Winches play a critical function in the mooring operation.
• They have to fulfil a dual purpose which includes:
controlling the mooring ropes during the move
maintaining the mooring lines in a proper spot while the ship is in
port.
• The mooring system of the ship needs to be updated when its
displacement is adjusted, or in reaction to changes in tide or current
conditions.
• Continuous changes to each rope may be made manually or
mechanically using constant tension winches.
Vessel motion control strategy using cable tension control with the
actuators
Operation of a Mooring Winch
• Electrical and hydraulic mooring winch power methods are the most
prevalent.
• Hydraulic engines endure a broad variety of speed fluctuations so
that a steady torque is maintained.
• These engines may be sluggish and have radial pistons or function at
a greater speed and have axial pistons
• The pistons in the former (Electrical) are frequently utilized with
direct stransmission, whereas those in the later (Hydraulic) are
connected by way of a differential (Carral et al., 2015).
c. Ship fittings
• The term "shipboard fittings" refers to just a few types of parts, such as
 bollards and bitts
 fairleads
stand rollers, and,
chocks, which are often used to moor or tow a ship.
• mooring system deck component design and manufacturing guidelines are
standardized certain document.
• The document is known as the Shipboard fittings and supporting hull
structures associated with towing and mooring on conventional vessels.
d. Fenders
• Devices that protect boats and berth structures from harm are known
as fenders.
• For instance they function to:
to absorb the impact energy during berthing
to reduce vessel motions during unloading operations by acting with
a suitable line arrangement
• There is a unique set of standards for each vessel, berth construction,
and berthing circumstances.
• Ship size, berthing method, location, tidal range and water depth are
among some of the factors that can influence which fender is chosen.
References
• Remery, G., 1974. Mooring forces induced by passing ships. In Proc.
Offshore Technology Conf. (paper Nº OTC2066) Houston, 1974.
• Bowers E., 1975. Long period oscillations for moored techniques of
moored ships subjected to short wave seas (transactions, paper w4).
The Royal Institution of Naval Architects.
• Carral Couce J., Carral Couce L., Fraguela Formoso, J, Villa Caro R.,
2015. Standardising the design and production of mooring winches
through more cohesive regulations: a necessary step, International
Journal of Maritime Engineering (RINA Transactions Part A)