Mooring

Ships will generally be berthed starboard side alongside the jetties. This involves swinging each vessel within the Voe.

There are four jetties located in deep water at Sullom Voe. Each jetty is of conventional T-shaped construction with four breasting dolphins in line with the jetty head. The mooring dolphins are offset from the line of breasting dolphins to provide an optimum lead for mooring lines. Vessels may land at a maximum angle of 8º to the jetty face. Quick release mooring hooks are fitted on all dolphins.

A  combination of large Barrel and Cone  fenders are fitted to the outer faces of each breasting dolphin. Each has a generous energy-absorbing capacity.

A purpose-built mooring boat will assist each mooring operation.

General mooring requirements
Strong winds are frequently experienced at Sullom Voe and may be accompanied by sudden gusts from any direction. Whilst alongside the jetty it is essential that moorings are tended carefully and conform to the requirements below.

• Masters should ensure that mooring lines are in good condition. Winch brakes or securing devices should be in efficient operating order and should have a holding power of at least 60% of the breaking load of the vessel’s mooring lines. 
• Any known defect in the vessel’s mooring system or limitation of mooring winch brakes should be reported to the Pilot and the Terminal before arrival in order that, if necessary, additional precautions may be agreed. 
• In order to avoid damage to loading arms and serious consequences of oil pollution, the vessels should be kept close alongside at all times. 
• It is recommended that wires (or wires fitted with synthetic fibre rope tails of at least 25% greater breaking load than the wire) should be used for all mooring lines. 
• The following mooring requirements shall apply to all tankers in excess of 10,000 GT and in general all mooring operations shall be conducted in accordance with the OCIMF Mooring Equipment Guidelines. 
  • Where a tanker has undergone a mooring audit on a previous visit to Sullom Voe, the ship must be moored exactly in accordance with the mooring plan. If, for any reason, this is not possible the ship should be secured, as appropriate, in compliance with the instructions detailed here and the details reported to the Harbour Master. Audited mooring plans shall not be altered without the approval of the Harbour Master. 
  • Where a tanker is equipped with synthetic mooring lines, or a random mixture of synthetic and wire mooring lines, the ship shall be secured by a minimum of four headlines/sternlines, four breastlines and two springs at each end of the ship. 
  • Where a tanker is equipped with wire mooring lines only, the ship shall be secured in accordance with the appropriate mooring guide plan. 
  • Where a tanker has not undergone a mooring audit and is not designed or equipped to comply with the requirements outlined above it shall be secured as near to these requirements as possible and, in any case, to the satisfaction of the master, the pilot and the Loading Master. If such ships cannot be secured satisfactorily, the loading arms must not be connected and the duty Harbour Master shall be contacted immediately. 
  • Mooring lines leading in the same direction of restraint shall be of similar material and construction throughout their lengths from jetty mooring point(s) to vessel’s securing point(s). 
  • Ships’ crew should not heave up on the mooring lines until signalled to do so by shore mooring crew. Heaving up should stop when signalled to do so (both arms raised). 
• Particular care should be taken to ensure sufficient transverse restraint from breast moorings. When synthetic fibre mooring lines are used, pretensioning of these lines on making fast will help prevent drift of the vessel away from the berth in ‘off the berth’ wind conditions. 
• As soon as the vessel is secured, brakes on all mooring winches should be firmly applied. Winches must not be left on automatic tensioning. Full steam pressure or power to all mooring winches should be maintained at all times when alongside. On split drum mooring winches, only one layer of rope shall be permitted on the working half of the drum. 
• An efficient watch must be maintained on the vessel’s moorings at all times to ensure that all lines are properly tensioned and tended when required. The deck watch should make regular checks that mooring winch brakes are applied at the correct setting. 

Notwithstanding any of the foregoing it is the Master’s responsibility to ensure that his vessel remains securely moored at all times

Actions to be taken in severe weather conditions

At least one tug shall be called out by the ship’s Master to assist in keeping any vessel alongside when all the following conditions exist:

1. The mean freeboard height of the vessel exceeds the mean draft.
2. The wind is gusting 45 knots or more or at such lesser speed as requested by the Marine Co-ordinator or Ship’s Master in consultation with Sullom Voe VTS.
3. When the wind direction is within an arc extending from 10 degrees to seaward of the berthing line, through north to 10 degrees seaward of the berthing line.

When a tug is called out as a result of the above conditions Sullom Voe VTS will notify the Master of the situation and request that the vessel be brought to a state of immediate readiness. Sullom Voe VTS will also notify the duty Harbour Master.

Tugs may be necessary to assist in keeping vessels alongside when some of the conditions above are absent. The Duty VTS Operator may call out tugs at his discretion if it is felt that the situation warrants such action.

A Pilot will board any vessel requiring tug assistance at the earliest opportunity and remain in attendance throughout the whole period a tug is required.

Vessels with large windage areas

Vessels with large windage areas will be subject to a wind restriction on berthing.

Windage should be calculated as LOA times mean freeboard.