foam buoy has a 10-inch diameter pipe used as a tension bar. The
lower padeye is connected to the upper link of the riser chain. A
moored vessel can be connected to the upper padeye by its anchor
chain, wire rope, or mooring hawsers.
Hawsepipe. A hawsepipe is a cylindrical tube passing through the
center of the buoy. The riser chain is passed through this tube and
its upper Iink is held on the top of the buoy with a slotted chain
plate. The lower portion of the riser chain within the hawsepipe is
protected from wear by a rubbing casting which encircles the chain
and greatly reduces the probability of chain abrasion. A moored
vessel ties directly to the riser chain. The buoy is nonstructural in
that the mooring load passes through the buoy via the riser chain.
Peg Top Buoy. This buoy is also used to support riser-type moorings, and
includes either a tension bar or hawsepipe. Peg top buoys are conically
shaped, with the top deck area considerably larger than the bottom
surface (See Figure B-l).
Non-Riser-Type Buoy. These buoys are larger than those used in riser-
type moorings since they have the additional weight of three or more
ground legs to support in the water column. These buoys have a swivel
at the top to which the moored vessel's anchor chain or hawser is
attached. Three or four padeyes, to which the anchor leg assemblies are
connected, are equally spaced around the buoy's hull (see Figure B-l).
Foam Buoy. This is the latest buoy design approved by the Navy. The
buoy consists of a tension bar encompassed by a rigid closed-cell interior
foam which is covered by a flexible cross-linked polyethylene foam
adhered to the rigid interior foam. The overall foam buoy is encased