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Old 07-16-2015, 03:25 AM   #40
Insequent
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City: Brisbane
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 4,262
Here is a link to a document setting out a few anchor parameters.

https://www.amsa.gov.au/forms-and-pu.../NRIP00092.pdf
Chapter 3 is the interesting part.

For Marin and others who wonder about ship anchor sizes, the standard defines 'Equipment number" and gives an equation with a number of variables. Basically Equipment number is a function of displacement, frontal area and profile area.

In addition, a document from a Wollongong, NSW workshop held in 2014 that considered the impacts of anchoring off coal ports whilst waiting to be loaded contains some items of interest. The document"Anchors aweigh: workshop summary" included the statement below as part of their overview of anchoring.

Anchor designs are numerous, however, the weight of the cable, or anchor chain alone ultimately hold the ship in position. A ratio, relating to the length of anchor chain to the water depth varies depending on the size of the vessel, from 3-5:1. Each link ~200kg contributes to an anchors holding capacity. Depending on ocean currents and wind, ships may swing around the point at which the cable rises from the seabed.
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