Floating moorage device for use with piles or dolphins

A floating mooring device adapted to be used with one or more piles projecting upwardly in a body of water. The device includes a float which is fastened to a cylindrical collar loosely surrounding the piles so that the float can move upwardly or downwardly along the pile in response to tidal action. A conventional mooring cleat or ring is carried by either the float or collar to which a line extending from a moored vessel may be fastened. Since vertical movement of the vessel responsive to tidal action is matched by the vertical movement of the float, the line may be tautly fastened to the float in order to prevent excessive movement of the vessel, yet tension of the line remains constant responsive to tidal action. The embodiment of the device used with a single pile includes a cylindrical float extending around a cylindrical inner sleeve which loosely surrounds the pile. In one embodiment the float is formed by an outer sleeve concentrically surrounding the inner sleeve with the space therebetween being either hollow or filled with a buoyant material. In another embodiment the float is formed by a plurality of axially spaced tires filled with a buoyant material surrounding the inner shell. The embodiment used with a pair of spaced-apart parallel piles or dolphins includes three interconnected collars, two of which loosely surround the pile, with the remaining collar being tightly secured to an elongated, cylindrical float.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to docking facilities for vessels, and more 
particularly, to a moorage device for securing a line carried by a vessel 
to a pile at a location on the pile which is horizontally fixed yet moves 
vertically with vertical movement of the vessel responsive to tidal 
action. 
2. Description of the Prior Art 
Floating moorage is commonly used in marinas throughout the United States. 
Such moorage utilizes a relatively wide mainwalk float projecting 
outwardly from the shore and a large number of relatively narrow finger 
floats of varying lengths projecting perpendicularly from the mainwalk 
float at spaced-apart locations. This commonly used mooring arrangement 
works very well for fairly small boats, but tidal surges often cause 
damage to floats when longer finger floats required by larger boats are 
used. The tidal action in most West Coast ports is not smooth or slowly 
varying. Instead, tidal surges; i.e., waves or water level variations, are 
generally produced which may have an amplitude of between one and six 
feet. The larger size of the finger floats required for the larger boats 
often causes the vertical movement of the larger boats to lose 
synchronization with the vertical movement of the mainwalkway floats. 
Under these circumstances, the larger boats move upwardly on the surge 
when the floating mainwalk piers are moving downwardly. This action causes 
the boat to collide into the mainwalk and finger floats often with 
sufficient force to cause severe damage to boeth the vessel and float. The 
more serious surges frequently occur during the winter months at times 
when moored vessels are often unattended. Consequently, widespread damage 
often occurs before it is discovered. 
The surge problem has, in many cases, prevented the use of the 
above-described floating moorage for larger vessels. Instead, a single 
floating mainwalk is used and a larger number of spaced-apart piles or 
groups of piles known as "dolphins" are driven into the sea bed along a 
line spaced from the edge of the mainwalk a distance approximately equal 
to the length of the vessels. The use of extra pile or dolphins cannot 
solve the surge problem and sometimes produce other problems as a result 
from a combination of surge plus tidal and wave action. It is desirable to 
prevent moored vessels from moving either transversely or longitudinally 
so that the vessel does not strike either the piles or the mainwalk. 
Consequently, lines extending between the vessel and the piles should be 
taut. However, taut lines extending around the piles often bind on the 
piles so that the lines are not able to move vertically along the pile as 
the vessel moves vertically responsive to tidal action. This results in 
extreme forces exerted on the pile by the boat which are frequently of 
sufficient magnitude to dislodge the pile from the sea floor. The vessel 
can then drift about with the pile, potentially causing a great deal of 
damage. Use of mainwalk and pile moorage thus presents the vessel operator 
with two options, neither of which is entirely satisfactory. The mooring 
lines can be left loose, in which case the vessel is free to move 
longitudinally or transversely to strike the mainwalk or piles; or the 
mooring line can be made taut, thereby risking removal of the pile from 
the sea floor. 
Floating tie-up buoys have been developed and used commercially. However, 
these buoys are generally either floats which are loosely anchored to the 
sea floor and thus do not restrict boat movement or they are cylindrical 
floats loosely positioned in vertical slots formed along the walls of 
locks. Neither of these existing float structures are satisfactory for use 
with a pile or dolphin to allow a vessel to be securely moored at a pile 
and yet respond to tidal changes. A structure attempting to solve the 
above-described problems is shown in Standard Handbook of Civil Engineers, 
Frederick S. Merritt, page 23-61. One such attempt includes a rod 
extending vertically along the side of a pile. A mooring ring loosely 
surrounds the rod for free vertical movement. This structure does not 
employ a float nor is it strong enough for extreme weather particularly 
where the rod must be long enough to accommodate the large tides ranges 
frequently found in many areas. 
SUMMARY OF THE INVENTION 
It is an object of the invention to provide a floating moorage device which 
allows a line extending from a vessel to be as taut as necessary to 
prevent longitudinal or transverse drift while accommodating vertical 
movements of the vessel resulting from tidal action. 
It is another object of the invention to provide a floating mooring device 
of the character described which can be easily retrofitted to existing 
moorage facilities. 
It is a different object of the invention to provide a floating mooring 
device which can prolong the life of the mooring float system and 
eliminate costly maintenance by preventing physical abuse to the floats. 
It is an additional object of the invention to provide a floating mooring 
device which can enable the development of new harbors or enlargement of 
existing harbors in areas where tidal or surge action has heretofor 
prevented the safe moorage of vessels without the environmentally 
unacceptable and cost-prohibitive addition of fixed breakwater protection. 
It is still another object of the invention to provide a mooring device 
which can be used with either a single guide pile or a pair of parallel 
piles. 
It is a further object of the invention to provide a floating mooring 
device of the character described which is relatively inexpensive, easy to 
fabricate, or may use discarded tires. 
These and other objects of the invention are provided by a mooring device 
for use with a pile projecting upwardly in a body of water. The device 
includes an inner shell which loosely surrounds the pile. A float 
surrounds the shell and carries a conventional mooring device such as a 
cleat or mooring ring. The float may be formed by a cylindrical outer 
shell concentrically fastened to the inner shell by interconnecting means. 
The space between the inner and outer shells may be either hollow or 
filled with a buoyant material to cause the device to float in water. 
Additionally, an annular resilient fender may extend circumferentially 
around the outer shell above the water line. The outer shell may be 
secured to the inner shell by an annular plate extending between the upper 
edges of the shells with the lower portions of the shells being 
interconnected by circumferentially spaced ribs. The float may also be 
formed by several axially stacked tires filled with a buoyant material 
which are concentrically secured to the inner shell. The tires may be 
connected to the inner shell and to each other by placing elongated 
fastening members through the side walls of the tires and securing the 
upper ends of the fastening members to an annular plate which extends 
outwardly from the inner shell to overlap the tires. The float can also be 
formed into shapes other than round, to fit non-cylindrical piles. The 
floating mooring device used with a pair of spaced-apart parallel pile 
includes a float and a pair of vertically spaced retainer members secured 
to the float which loosely surround the pile to allow the float to remain 
on the surface of the water during wave or tidal action. The retaining 
members may include three interconnected collars, two of which loosely 
surround respective pile, with the remaining collar being tightly secured 
to the float. A connecting plate extending between the collars of each 
retaining member may carry a conventional mooring device such as a cleat 
or mooring ring.

DETAILED DESCRIPTION OF THE INVENTION 
A typical moorage facility which may utilize the inventive floating mooring 
device is illustrated in FIG. 1. The facility includes a conventional 
mainwalk 10 formed by a plurality of conventional mainwalk floats. A 
relatively short, narrow finger float 12 projects perpendicularly from the 
mainwalk 10 and is secured thereto by triangularly shaped gussets 14. A 
fairly large vessel 16, which may be on the order of 50 feet or more in 
length, is positioned adjacent the finger float 12. It must be emphasized, 
however, that the vessel 16 is not tied to the finger float 12 so the 
aforementioned impact problem cannot occur. Instead, the vessel 16 is 
secured to four of the inventive floating mooring devices 18 surrounding 
respective piles 20 by taut lines 22. Since the lines 22 are taut, the 
vessel is incapable of moving either longitudinally or transversely so 
that it will not strike either the mainwalk 10, the finger float 12 or the 
pile 20 even when relatively large waves or vessel wakes are encountered. 
However, since the mooring device 18 floats at the surface of the water as 
described hereinafter, the tension on lines 22 does not vary as the 
vertical position of the vessel 16 varies responsive to tidal action. 
An isometric view of one embodiment of the mooring device of FIG. 1 is 
illustrated in FIG. 2. The pile 20 is driven into the sea floor 24 a 
suitable distance by conventional means so that it is relatively 
immovable. The mooring device 18, which loosely surrounds the pile 20, 
projects for about 40 percent of its length above waterline 26, while the 
remaining 60 percent is submerged. It will be understood, however, that 
the degree to which the device 18 is submerged is not critical so long as 
at least a portion of it is at or above the waterline 26. A pair of 
conventional mooring cleats 28 are mounted on the upper surface of the 
float 18 to allow the lines 22 to be secured to the device 18. 
The structural details of the embodiment of FIGS. 1 and 2 are illustrated 
in FIG. 3. An inner shell 40, which is preferably a length of tubular 
pipe, surrounds the pile 20. The inside diameter of the inner shell 40 is 
sufficiently larger than the outside diameter of the pile 20 so that it is 
free to move vertically along the pile 20. The upper and lower edges of 
the shell 40 are chamfered outwardly at 42 to ensure that the edges do not 
dig into or catch the sides of the pile 20. An outer shell 44, which may 
also be a length of tubular pipe, concentrically surrounds the inner shell 
40. The outer shell 44 is connected to the inner shell 40 by an annular 
plate 46 extending between the upper edges of the inner and outer shells 
40, 44, respectively are preferably interconnected by circumferentially 
spaced ribs or spokes 47 particularly where the space between the inner 
and outer shells 40, 44, respectively, particularly where the space 
between the inner and outer shells 40, 44, respectively, is hollow. 
However, this space may be filled with a buoyant material 45 such as 
polystyrene or similar foam which maintains the concentric positioning of 
the shells 40, 44, thus making the ribs 47 unnecessary. If desired, an 
annular resilient fender 48 may be secured about the outer shell 44 above 
the waterline 24. The fender 48 may be formed of any suitable resilient 
material, such as rubber, resilient plastic or the like. The mooring cleat 
28, illustrated in FIG. 2, is mounted on the annular plate 46 by suitable 
fasteners. Other conventional marine fixtures such as mooring rings may 
also be mounted on either the annular plate 46 or the outer surface of the 
outer shell 44. 
An alternative embodiment of the mooring device is illustrated in FIG. 4 in 
which features which are identical to the embodiment of FIG. 3 are 
identically numbered. The basic difference between the embodiment of FIG. 
4 and the embodiment of FIGS. 1-3 is that the embodiment of FIG. 4 employs 
as a float a plurality of axially spaced tires 50 filled with a buoyant 
material 52 which surround the inner shell 40. The side walls of the tires 
50 have formed therein aligned holes 54 through which extends rods 56. 
Individual tubular spacers 58 are imbedded in the buoyant material 52 in 
alignment with the holes 54. The spacers 58 have a diameter which is 
substantially larger than the diameter of the either the rod 56 or the 
holes 54 so that the spacers 58 clamp the side walls of the tires 50 when 
the spacers are compressed as explained hereinafter. The rod 56 projects 
through holes formed in an annular plate 60 which is fastened to the upper 
edge of the inner shell 40 such as by welding. Nuts 62 are tightened onto 
the ends of the rods 56 so that when the nuts 62 are threaded toward each 
other the spacers 58 clamp the side walls of the tires 50 as explained 
above and secure the tires to the annular plate. The primary advantages of 
this embodiment are that it utilizes a waste material, namely, spent 
tires, and the tires provide a resiliency to act as a resilient fender. 
A third embodiment of the invention which is used with pairs of 
spaced-apart, parallel piles 60 or dolphins projecting upwardly above the 
waterline 62 is illustrated in FIGS. 5 and 6. The piles 60 are secured to 
each other at their upper ends by conventional bolts 64 and backing plates 
66 having nuts 68 torqued onto their ends. The spacing between the pile 60 
is maintained by a block 70 positioned between the pile 60. An elongated, 
cylindrical float 71 is carried by a pair of spaced-apart upper and lower 
retainers 72, 74 which loosely surround the piles 60 to allow vertical 
movement along the piles responsive to tidal action. 
With reference also, now, to FIG. 5, the retaining members 72, 74 include 
three annular collars 76, two of which 76a, 76b loosely surround the piles 
60, while the remaining collar 76c is secured to the float 71 by bolts 78, 
nuts 80. As illustrated in FIG. 5, the upper and lower edges of the 
collars 76 are chamfered outwardly at 82 to prevent the collars 76 from 
digging into or catching the piles 60 as they move vertically responsive 
to tidal action. As illustrated in FIG. 6, the collars 76a, 76b 
surrounding the piles 60 carry respective mooring eyes 84 to which lines 
extending from a vessel may be secured. The primary advantage of the 
embodiment of FIGS. 5 and 6 is that it allows utilization of two piles 
where additional mooring strength is needed. 
Although cylindrical piles 20 are illustrated herein, it is to be 
understood that piles having other cross-sectional shapes can be used. 
Also, although wood piles 20 are illustrated herein, piles formed of other 
materials, such as concrete, may be used. If a different pile 
cross-section were to be used, such as a steel "H" pile, it may be 
desirable to change the devices outer shell 44 from round to square, which 
conforms to the square inside hole requirement needed for the "H" pile. If 
either the steel or concrete piling are utilized, the usage of rollers and 
preferably rubber clad rollers are necessary. These rollers would be 
mounted at both the top and bottom of the inside tube 40 and their use 
cushions the inside tube 40 from the steel or concrete piling, and not 
only quiets the impact noises but prevents binding and shock damage to the 
piling 20. 
The inventive floating mooring device thus allows relatively large vessels 
to be safely and easily moored at conventional moorage facilities.