Installation Guide

PRIMUS WIND POWER DOCUMENT #0070 REV C
PRIMUS WIND POWER Page 10 of 26
2/4/05
Step 4: Guy Wire Anchor Installation
There are four types of anchors that are most commonly used with our towers; screw in “Auger”
type anchors, hammer driven “duckbill” anchors, cast concrete anchors and expansion bolts (for use
only in solid rock). What anchor should be used depends on the soil type that the anchors will
be placed in. See the following table for our suggestions:
Soil Type
Sand
Loose Gravel
Loam
Clay
Rocky Soil
Gravely Soil
Solid (Soft) Rock
Solid (Hard) Rock
Recommended Anchor
Buried Concrete
Buried Concrete
Auger
Duckbill
Duckbill
Auger or Duckbill
Large, Long Expansion Bolt
Smaller Expansion Bolt
Alternatives
None
None
Duckbill,Buried Concrete
Auger, Buried Concrete
Buried Concrete
Buried Concrete
Large Eye Bolt + Cement
None
The loads on a single anchor can exceed 500 lb. in a 100-mph gale. Make sure that the anchors
chosen can withstand at least this much force or the tower will have to be lowered during storms.
Augers and Duckbill anchors are frequently available at mobile home supply stores. Augers are
also available the dealer where your turbine was purchased or from our factory, however when
shipping costs are added they may be more expensive than if they are purchased locally. Expansion
bolts for anchoring in solid rock can be purchased at most hardware stores.
Augers: If the soil conditions make their use feasible, augers are the simplest anchors to install.
Augers screw into the ground using either a piece of wood, pipe or rod as a “cheater bar”. If a
mistake is made or if the tower must be removed an auger can be “unscrewed” out of the ground
and reused. They depend on the soil holding together for the pullout strength and are not suitable
for sand or loose gravel. In addition, if the soil is rocky or clay-like you may have difficulty
screwing them in.
An auger is usually installed by screwing it straight into the ground to get it started and then tilting
it to the desired angle once it is into the ground a few inches. A substantial downward pressure is
usually necessary to get an auger started. Screw the augers in as far as possible for the greatest
strength.