U.S. patent number 3,683,521 [Application Number 05/016,751] was granted by the patent office on 1972-08-15 for submersible dredge.
This patent grant is currently assigned to Ocean Science & Engineering, Inc.. Invention is credited to Robert J. Jantzen, Theodore F. Mangels, Jack I. McLelland, Albert H. Sloan.
United States Patent |
3,683,521 |
Sloan , et al. |
August 15, 1972 |
SUBMERSIBLE DREDGE
Abstract
A dredging system including a submersible, occupant-operated
vehicle having an excavating tool carried thereby; a conduit
extending from said tool to a location where said excavated
material is to be deposited; a shore installation; and power and
air conduits connecting said installations with the vehicle. The
system is applicable to the excavation of large areas such as
submerged deposits of sand and silt; the formation of narrow, deep
trenches such as those utilized for various pipelines and cables;
and the grading of level or specifically contoured areas for
preparing the bottom for prefabricated structures.
Inventors: |
Sloan; Albert H. (Fort
Lauderdale, FL), McLelland; Jack I. (Palos Verdes Peninsula,
CA), Mangels; Theodore F. (Newport Beach, CA), Jantzen;
Robert J. (Baltimore, MD) |
Assignee: |
Ocean Science & Engineering,
Inc. (Washington, DC)
|
Family
ID: |
26689017 |
Appl.
No.: |
05/016,751 |
Filed: |
March 5, 1970 |
Current U.S.
Class: |
37/313; 405/185;
277/512; 277/583; 277/646; 277/518; 37/326; 37/346; 37/334;
277/511; 37/195 |
Current CPC
Class: |
E02F
3/8858 (20130101); B63C 11/40 (20130101) |
Current International
Class: |
B63C
11/00 (20060101); B63C 11/40 (20060101); E02F
3/88 (20060101); B63c 011/00 (); E02f 003/88 () |
Field of
Search: |
;37/56,67,72,73,58
;61/69 ;277/9,34.3 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Pulfrey; Robert E.
Assistant Examiner: Crowder; Clifford D.
Claims
We claim:
1. A dredging system comprising
a self-propelled submergible vehicle having an enclosed operator
chamber and a separately enclosed equipment hull,
a boom pivotally mounted to said vehicle,
an excavating tool mounted on said boom,
a suction conduit having one end disposed at said tool and the
other end thereof leading to a remote location,
a suction producing pump intermediate the length of said conduit
and mounted to the exterior of both said hull and said chamber,
power means within said equipment hull,
a drive shaft extending through an opening in said equipment hull
and drivingly connecting said power means to said pump, and means
sealing said opening.
2. The system of claim 1 wherein said means sealing said opening is
a packing gland which circumscribes said shaft where it extends
through said hull, wherein separate sealing means is provided to
permit the replacement of said packing gland from the interior of
said vehicle.
3. The system of claim 2 wherein said separate sealing means
includes an annular inflatable seal positioned between the
periphery of said opening and said shaft whereby said seal is
inflated to prevent water from entering said equipment hull through
said opening when said gland is replaced.
4. The system of claim 3 wherein said packing gland is located
interiorly of said seal whereby access thereto from the interior of
said vehicle is provided.
5. A dredging system comprising an installation having sources of
air and power located near the shore of the area to be dredged,
a connection member located centrally of the area to be
dredged,
a buried conduit extending from the shore to said member,
a submersible excavation vehicle having an equipment hull,
a second conduit extending from said member to said vehicle,
a power line, communication line, and air hose extending between
said installation and said vehicle,
buoyant means for suspending said second conduit from the bottom
surface of the area being dredged and said buoyant means are
comprised of a series of lighter than water members attached at
spaced intervals along the length of said second conduit,
a boom pivotally mounted externally of said vehicle,
a tool mounted on said boom,
a suction pump mounted exteriorly of said equipment hull,
a suction conduit communicating said tool with said pump,
a power means within said equipment hull,
a drive shaft extending through an opening in said equipment hull
and drivingly connected to said pump, and
means sealing said opening.
6. The system of claim 5 wherein traction members are mounted on
said vehicle and power means within said vehicle drive said
members.
7. A submersible vessel comprising
a framework,
a first enclosed hull mounted on said framework containing quarters
for an operating crew,
a boom,
means pivotally connecting said boom to said first hull,
an excavating tool carried by said boom,
an enclosed equipment hull separate from said first hull,
a suction pump mounted on said framework adjacent to and to the
exterior of said equipment hull,
a drive means within said equipment hull,
a drive shaft between said drive means and said pump and extending
through an opening in said equipment hull,
a packing gland sealing said opening,
means to seal said opening to allow replacement of said packing
gland when said vehicle is beneath the surface of the water,
a conduit between said excavating tool and said pump, and
a second conduit extending from said pump to an area where
excavated material is to be deposited.
8. The vehicle of claim 7 wherein hydraulic means control the
pivotal movement of said boom.
9. The vehicle of claim 8 wherein said hydraulic means are
hydraulic jacks under the control of an operator within said first
hull.
10. The vehicle of claim 9 wherein a passageway extends between
said first and said equipment hulls and closure means can close
said passageway.
11. The vehicle of claim 10 wherein a plurality of outriggers
extend from said vehicle, spuds are attached to said outriggers and
control means can selectively lower said spuds into the surface
over which said vehicle rests whereby said vehicle can resist
torque forces caused by a swinging movement of said boom.
Description
Heretofore, dredging operations have been primarily conducted from
floating platforms. Such systems are restricted to relatively calm
water conditions and therefore have been inefficient or
inapplicable for many dredging operations. Further, dredging
operations conducted from the water's surface are restricted to
relatively shallow depths by limitations of suction head, or in the
case of bucket dredges, by the feasible ladder length.
A principal objective of this invention is to provide a system for
underwater dredging wherein a self-contained dredging vehicle,
having quarters and facilities for an operating crew, is capable of
excavating on the bottom of a body of water generally without
regard to water surface conditions.
Another principal objective of this invention is to reduce
maintenance problems by mounting the slurry conduits and the
suction pump external to the hull of the vehicle housing the
electrical and mechanical equipment within the hull. As a result,
the crew has access to the equipment for inspection and maintenance
thereof at comfortable atmospheric conditions. The power equipment
for the suction pump is located within the hull of the vehicle and
the pump itself is exterior thereof. This arrangement requires that
a drive shaft must extend through the vehicle hull. A further
objective of this invention is to provide a novel inflatable seal
about the shaft which permits the inspection and replacement of the
shaft packing glands from the vehicle's interior while
submerged.
Another objective of this invention is to provide a dredging
apparatus for operation on the bottom of a body of water which
requires no surface components other than power and air supply
lines communicating from the apparatus to the shore or other
surface installation.
A still further objective of this invention is to provide a
dredging vehicle which permits its operator to have direct visual
contact with the excavating tool during submerged dredging
operation whereby a more efficient dredging operation is assured.
The vehicle is provided with an operator's chamber with means for
maintaining the interior atmosphere thereof at conditions
compatible with human requirements for extended periods of
time.
Another important objective of this invention is to provide the
underwater vehicle of this invention with an air-water lock chamber
for the ingress and egress of replacement crews while the dredge
remains submerged at the area of dredging operations.
A further objective of this invention is to provide the submergible
vehicle of this invention with an operator-controlled,
tool-carrying boom. The controls available to the operator for
swinging the boom include circuitry for pre-setting boom swing at
predetermined rates with further means provided to reduce the rate
of boom swing upon a sensing that the lateral forces exerted
against the boom exceed a pre-set force level. Thus, when the tool
is not excavating materials as rapidly as the tool is being moved
into the material, the circuitry will reduce the rate of swing
until the desired pre-set force is reached. Further, if the tool
should become buried in the material to be excavated, the controls
will decrease the lateral force until the rate of swing becomes
zero.
A still further objective of this invention is in the provision of
an adjustable valve, operable from within the vehicle, for purposes
of permitting additional water to enter the suction conduit of the
system between the tool and the pump. If the tool, or the conduit
between the tool and pump, becomes fully or partially clogged, it
is possible by operating this valve to adjust and control the
proportion of solids and water in the slurry mixture until the
conduit is cleared. Also the slurry mixture can be varied for
increased efficiency in the removal thereof.
Another objective of this invention is to provide means to vary the
submerged weight of the vehicle by increasing or decreasing the
volume of sea water in the vehicle ballast tanks. By so controlling
the weight of the vehicle, the traction between its traction
members and the bottom surface can be adjusted.
A still further objective of this invention is to provide outrigger
spuds which can be inserted into the bottom surface so as to resist
lateral twist or movement of the vehicle during boom swing. The
spuds serve the additional function of leveling the vehicle when
desired.
These and other objectives of the invention will become more
apparent to those skilled in the art by reference to the following
detailed description when viewed in light of the accompanying
drawings wherein:
FIG. 1 is an underwater perspective of the dredging system;
FIG. 2 is a side elevation of the submergible vehicle;
FIG. 3 is a top plan of the vehicle with portions broken away;
FIG. 4 is a side elevation of the vehicle with portions broken
away;
FIG. 4A is a diagrammatic showing of one component of the
submersible vehicle;
FIG. 4B is a diagrammatic showing of a portion of the hydraulic
system;
FIG. 5 is a cross-section along the line 5--5 of FIG. 4;
FIG. 6 is a diagrammatic cross-section of a seal assembly; and
FIG. 6A is an enlargement of a portion of FIG. 6.
Referring now to the drawings wherein like numerals indicate like
elements, the numeral 10 indicates the dredging system of this
invention. The dredging system is comprised generally of a
submersible vehicle 12, a control station 14, a dredging conduit
16, and an air-communication-power cable assembly 18.
As duscussed in the objectives, the purpose of this dredging system
is to remove materials from the vicinity of the vehicle 12 to a
remote location such as that indicated by the letters R and R1. The
system herein described has wide application and is uniquely
adaptable for contouring, removing material and forming trenches on
the bottom of a body of water.
The slurry conduit or dredging hose 16 is comprised of a series of
segments or sections 17 which are attached together by conventional
means. The conduit leads from the vehicle 12 to a stakedown
position P. At position P, a Y-connection can be placed in the line
by known methods. From position P, the excavated material recovered
by the vehicle 12 can be exhausted either to a location R or to
location R1. Installation 14 is relatively fixed and includes such
equipment as power generators, air compressors and the like. The
installation 14 is located as near to the dredging site as
possible. The conduit portion 19 between the shore and position P,
through the surf area, is normally buried. At the Y-connection, a
second conduit section 22 can be readied while vehicle 12 is
excavating in the area shown. An area of several miles along the
shoreline can be controlled from the single installation 14.
The air-communication-power cable assembly 18 extends between the
surface installation 14 and the vehicle 12. Under some conditions,
it is advisable to attach buoys 26 at intervals along the length of
the conduit 16. The buoyancy of these members is set to cause the
hose to be suspended above the bottom whereby drag on the dredge is
reduced and the hose is protected from the bottom surface. When
pumping a heavy slurry, it is, of course, advisable to have the
support of the bottom surface and the buoy can be so designed. The
cable assembly 18 can be secured to these buoyancy means.
The submersible vehicle 12 includes an operator chamber and an
equipment chamber which are respectively defined by hulls 32 and
30. The hulls 30 and 32 are mounted on a framework 31 which
includes a pair of spaced I-beams 34. A pair of ground-engaging
track assemblies 36 and 38 are mounted on either side of the
framework 31. Mounted forwardly of the vehicle 12 is a boom member
generally indicated by the numeral 40. The boom is generally
comprised of tubular beams 41, 42 and 43. At their outermost ends,
the beams are welded to the exterior of the conduit section 44. At
its outermost end, the conduit 44 is adapted to receive a plurality
of replaceable cutter-head assemblies 48. The disclosed cutter-head
assembly 50 is driven by a hydraulic motor 52. The motor 52
receives hydraulic fluid through conventional hydraulic circuitry
53. Intermediate their lengths, the beam members 41, 42 and 43 are
spaced and joined by braces or struts 54 and 56.
A fifth wheel assembly 60 is mounted at the forward end of the
vehicle. The fifth wheel assembly includes a rotatable upper plate
62 having lugs 64 extending upwardly therefrom. Plate 62 is
rotatable about the vertical axis 66 as shown in FIGS. 4 and 4A.
The boom assembly 40 is mounted for vertical movement about the
axis 67 of lugs 64. The turntable is provided with stop means which
limit the boom to a 45.degree. swing to each side of the
longitudinal center line of the vehicle 12. Thus, it can be seen
that the boom 40 is mounted to vehicle 12 with limited universal
movement. Movement is controlled by a plurality of hydraulic jacks.
A hydraulic jack 70 is provided for movement in the vertical plane.
The jack 70 has cylinder end 71 pivotally secured to an ear 72 at
the top of hull 32 and its piston end connected to ear 74 mounted
to the boom assembly 40 near braces or struts 54 and 56. The
turntable plate 62 is under the control of a pair of hydraulic
jacks 65. The jacks 65 have their cylinder ends pivotally connected
to a lug member 63 which is attached to the vehicle framework and
their piston ends pivotally connected to turntable plate 62 at
joints 71 on either side of axis 66. With conventional hydraulic
controls, an operator seated on chair 75 and looking through window
76, is able to observe and control the position and direction of
assembly 48. As mentioned above, control circuitry 77 permits him
to pre-set movement at a desired rate.
The conduit section 44 spans the distance between the excavating
tool 48 and the intake opening of an impeller-type suction pump 80.
A portion 81 of conduit 44 is flexible to permit swinging of the
boom. The pump 80 exhausts through a conduit segment 82 which
comprises the first of the sections making up the conduit 16. As
seen best in FIG. 1, the conduit line 16 is supported by and
extends over hull 30.
The principal power means for vehicle 12 are located within the
chamber 30. In particular, reference is made to power source 86
having its power output transmitted to impeller pump 80 by way of a
drive shaft 88. Between the motor 86 and shaft 88 is an
electro-magnetic coupling 89 to vary the speed of the pump and to
isolate the motor from the pump when starting the motor. A gear
reduction unit 90 is located between the coupling 89 and pump 80.
Also within the hull 30 is an auxiliary motor and pump 91 to power
the hydraulic elements and control systems. Other auxiliary
equipment is generally located diagrammatically at 93. All of the
above mechanical equipment is driven by electricity received
through cable assembly 18.
The operator's quarters enclosed within the hull 32 is a compact
unit having the operator seat 95 and a bed 96 for the off-duty
operator. The hull also includes a small galley 98. Such an
arrangement permits a crew to remain submerged for many hours.
In submerged equipment of the prior art, it has oftentimes been
difficult to repair, service and maintain the engine motors and
pumps of the submerged equipment. In the system of this invention,
the more delicate and difficult to repair items are housed within
the chamber 30 which is maintained at atmospheric conditions. A
passageway 100 is provided to enable the operator in chamber 32 to
enter the power equipment chamber 30. Side-hung hatches 101 and 103
isolate the hull 30 from hull 32 for safety reasons. These hatches
also isolate the crew from the heat and noise generated by the
mechanical equipment.
A bulkhead 102 across chamber 30 forms a work chamber 104. A
sealing assembly 106 is disposed about shaft 88 at opening 108 to
isolate the chamber 104 from the exterior of hull 30. Assembly 106
can best be understood with reference to the enlarged, somewhat
diagrammatic cross-sections of FIGS. 6 and 6A. The shaft 88 extends
to pump 80 through the opening 114 of hull 30. The assembly is
comprised of an annular ring 110 having annular flanges 120 and 122
at either side thereof. An inwardly directed flange 126, with that
portion of hull 30 adjacent opening 108, forms an annular chamber
128 for the reception of an outwardly extending flange 130 of the
drive flange 88. By receiving the shaft 130 in chamber 128,
longitudinal displacement of the drive shaft is prevented.
Inwardly of flange 126 is an annular, inflatable sealing ring 132
and a packing gland 134. The packing gland is retained in place by
retainer plate 136 which is bolted or otherwise secured to flange
122. Due to the rotation of shaft 88, the packing 134 needs
replacement at regular intervals. The inflatable seal 132 is
utilized to seal the chamber 104 from the surrounding water during
the replacement of the packing. Note that the seal is communicated
to a source of compressed air by way of line 140. The packings are
communicated to a source of water via a line 142 for lubricating
purposes during initial start up. When replacing the packing gland,
the seal 132 is inflated, the packings 134 are replaced. Upon
completion, seal 132 is deflated and plate 136 is replaced. In its
deflated condition, the seal 132 is not in any particular
engagement with the shaft and thus will not wear because of
frictional engagement with the shaft. Note that a second packing
112 of bulkhead 102 is equipped with an inflatable seal 113 for the
same purposes. In practice, a certain amount of lubricating water
is permitted to leak through packings 134 and remain within the
chamber 104. As diagrammatically seen in FIG. 6, the level of this
bilge is maintained by way of valve assembly 144 in outlet assembly
146 by having pressure raised beyond the ambient outside pressure.
An air compressor 145 maintains the pressure in 104 at a slightly
elevated pressure over that maintained in hulls 30 and 32 and above
the ambient water pressures. Since the pressure is elevated
slightly above exterior ambient water pressure, inflow is prevented
through the packing gland when replacing same. By elevating
pressure via 145, leakage is also controlled.
The shaft 88 is rotatably supported by a bearing 147 within hull 30
and by a bearing 149 within chamber 104. A mechanic can gain head
access to chamber 104 through opening 151 and hand access through
opening 153. These openings are normally closed by coverlets 155
and 157 respectively.
Returning now to the exterior of the vehicle, it can be seen that
extending outwardly from the framework 31 are four stabilizing
spuds 150, 152, 154 and 156. The spuds are hydraulically driven
into the bottom surface in those locations where stability of the
vehicle cannot be maintained by the tracks alone. The spuds are
used to resist torque induced by boom movement and to level the
vehicle to assure boom swing in the horizontal plane. The
earth-engaging ends of the spuds are actually the piston members of
double-acting cylinders 150a, 152a, 154a and 156a. These
double-acting cylinders are hydraulically controlled from within
the chamber 32 by conventional controls.
A passageway 160 leads outwardly from chamber 30 to an escape hatch
162. The escape hatch is of conventional design and is adapted to
receive a pressurized bell member B which lowers replacement crews
to the vehicle. At relatively shallow depths swimmers can gain
access through the bottom of the hatch. Divers at deeper levels can
also gain access by this means.
In setting up for a dredging operation, shore installation 14 is
located as near the dredging operation as possible. In some
circumstances, the shore installation is actually located on a
floating platform. The shore installation includes the apparatus
necessary to furnish air, power and communication to the vehicle 12
via the cable assembly 18. A station P is located on the bottom
surface centrally of the area to be dredged. Conduit sections are
laid from location P to the vehicle 12 which is previously driven
to the dredging area. Note that the dredging conduit can be folded
or nested to give some play to conduit line 16 as the vehicle 12
moves forwardly.
In a general manner, while there has been disclosed effective and
efficient embodiments of the invention is not limited to such
embodiments as there might be changes made in the arrangement,
disposition, and form of the parts without departing from the
principle of the present invention.
* * * * *