Anchors

General Information on Anchors

CRITERIA FOR HOLDING POWER

The holding power comparence of an anchor can be derived from the following formula: fluke area (m) x penetration(m) = m x m = m = tons

CRITERIA FOR HOLDING POWER

Building up Resistance

CRITERIA FOR HOLDING POWER

A Minimal Amount of Resistance

CRITERIA FOR HOLDING POWER

A Minimal Amount of Resistance

CRITERIA FOR HOLDING POWER

Clod forming (square shank) can effect breaking out

CRITERIA FOR HOLDING POWER

Clod cutting (by shank shape)

CRITERIA FOR HOLDING POWER In hard soil a 50 degree fluke shank angle will obstruct penetration and the anchor will begin to trip faill aside and slide along the seabed.

CRITERIA FOR HOLDING POWER In hard soil an achor with a fluke angle of 32 degrees will give the highest holding power.

Note: The fluke area is limited by strength; penetration, however, is restrited by the anchor type and the chain (wire).

CRITERIA FOR HOLDING POWER

A decreased anchor penetration duo to the chain; it is partly compensated by the holding power of the chain.

CRITERIA FOR HOLDING POWER

The wire allows the anchor to penetrate deeper, which results in a greater holding power

CRITERIA FOR HOLDING POWER

HOLDING POWER OF ANCHOR

The holding power is a combination of the following parameters

  • A) the weight of the anchor
  • B) the weight of the disturbed soil
  • C) the friction of the disturbed along fractured lines

 

 

  • D) friction between fluke surface and soil (fluke area)
  • E) the compression of shank and cable
HOLDING POWER OF ANCHOR

If used in mud, an anchor with a 32 degree fluke shank angle will not penetrate sufficiently

Fluke/Shank Angle

The fluke shank angle is one of the factors that determines the soil penetration of an anchor

In normal anchor grounds and hard soils, a 32 degree fluke shank angle must be used. In soft mud, a 50 degree fluke shank angle offers optimal penetration

If an anchor is used with an incorrect fluke shank angle, it will negatively influence performance. This is true for all anchor types.