EFFECTIVENESS OF FMS SCREW ANCHORS
FMS SCREW ANCHORS
The Fruits of Our Labor
HISTORY OF SCREW ANCHORS
Screw Anchors or spiral anchors (as they are sometimes referred to), is not a new technology. They were developed by Alexander Mitchell in 1833, a blind English brick maker who is credited with the design of the ‘screw pile’ for anchoring lighthouses in tidal basins around the coast of England. In the 1950’s the ‘screw pile’ was given a new lease of life by A.B Chance company who developed a power installed screw anchor for resisting loads. This innovative pile system worked by applying torque to the anchor and screwing it in to soil. The development of high torque drives along with advancements in hydraulics, has opened up their use on a much wider scale.
EARLY ADAPTION FOR LONG LINE MUSSEL FARMING
Traditionally the aquaculture industry in New Zealand has used concrete blocks or Danforth anchors to moor their long lines. However, as farming moves into more open water, even 10 tonne concrete blocks can drag, wreaking havoc on a farms productivity. Once installed a screw anchor will remain locked in position for decades. Thus improving a farms potential for a higher yield.
The first spiral anchors used in the New Zealand aquaculture industry were modeled on a US swamp anchor used by the power board to back stay power poles on difficult terrain.
THE FMS SHAFTED SCREW ANCHOR
At FMS we install shaft screw anchors for the aquaculture industry. Our point of difference is that we do this in the marine environment, using the farmers own aquaculture vessels. Our anchors are installed from the surface, with little or no diving. The development of the FMS portable system, means that screw anchors are a more viable mooring option for our clients.