Classification Society rules on Anchors and Chains

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The equipment is therefore not designed to hold a ship off fully exposed coasts in rough weather or to stop a ship which is moving or drifting. In this condition the loads on the anchoring equipment increase to such an extent that its components may be damaged or lost due to the high energy forces generated particularly in large ships.
The anchoring equipment presently required herewith is designed to hold the ship in good holding ground in conditions such as to avoid dragging of the anchor. In poor holding ground the holding power of the anchors will be significantly reduced.
A good holding ground as defined by the above stated requirements are;

  • A current  speed  of not more than  5  m/sec (max tide current  speed)
  • A  wind  speed  of not more than  25m/sec
  • Depth of  water ranging  between  85M and 100M .
  • The ground should  be  sandy  or  muddy and  not  rocky

A good anchoring ground is normally marked on the chart by an anchor symbol on hydro-graphic charts giving details of port anchorages.
The length of chain provided varies between 86 m to 770 m depending on the size and dimensions of the ship.
To find the equipment details for anchors and chains as given in the rigging tables of the classification rules, the procedure is adopted as per classification .

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