US3310892A

US3310892A - Submarine dredge

Info

Publication number: US3310892A
Application number: US334740A
Authority: US
Inventors: Ernest W Spannhake; Prehn Henri
Original assignee: John J Mcmullen Associates Inc
Current assignee: John J Mcmullen Associates Inc
Priority date: 1963-12-31
Filing date: 1963-12-31
Publication date: 1967-03-28
Anticipated expiration: 1984-03-28

Description

Mafia 3%? E. w. SPANNHAKE ETAL. 3, 7

SUBMARINE DREDGE Filed Dec. 31, 1963 5 Sheets-Sheet 1 INVENTQRS [7%9513 MKS 0x219,

Henry; Prekm I ATTO NEYS March 2, 1%? E- w. SPANNHAKE ETAL 3,31%

SUBMARINE DREDGE ATTORNEYS Mmdh 3%? E. w. SPANNHAKE ETAL 3,

SUBMARINE DREDGE Filed Dec. 51, 1963 5 Sheets-Sheet 4 ATTORNEY 6 SUBMARINE DREDGE 5 Sheets-Sheet 5 Filed Dec. 31, 1963 INVENTORS mm fi m P fiw n 3,310,892 SUBMARINE DREDGE Ernest W. Spannhake, Kinnelon Borough, N.J., and Henri Prehn, Roslyn Heights, N .Y., assignors to John J. McMullen Associates, Inc, New York, N.Y., a corporation of New York Filed Dec. 31, 1963, Ser. No. 334,740 Claims. (Cl. 37-56) The present invention relates to submerged vessels such as submarine dredges.

Basically, a submarine dredge is a submersible vessel for digging a trench along the bottom of a body of water. In one form, the dredge is manned by personnel while it is submerged and consequently, access to and from the submerged dredge becomes a special problem.

In one type of submarine dredge that has been proposed, access to the dredge is achieved by a pressure chamber (similar to a submarine rescue chamber) which plies between a floating power supply vessel and the dredge. In bad weather, access to and from the dredge is awkward and risky. Moreover, the power supply vessel must be anchored in the vicinity of the dredge, and this requirement is a handicap.

In another type of submarine dredge, access to the dredge is achieved through a hollow tower which is rigidly attached to the dredge and extends vertically to a landing deck at the top of the tower above the water. The operation of this type of dredge is limited to a body of water that does not vary greatly in depth.

It is an object of the present invention to provide improved means for transferring either personnel or supplies to a submerged vessel.

Another object is to provide an improved submarine dredge that can be safely manned and operated underwater even if the weather is bad, the body of water is very rough, and the water varies greatly in depth.

A further object is to provide an improved submarine dredge that does not require the presence of a nearby power supply vessel to operate the dredge.

Still another object is to provide a submarine dredge that is more eflicient than submarine dredges heretofore. known in the art.

The foregoing objects are achieved by a submarine vessel which has a snorkel tube extending therefrom. One end of the snorkel tube is attached to the vessel by a universal joint. When the vessel is submerged in a body of water, the other end of the snorkel tube is free-floating at the surface of the water. The snorkel tube houses: means for transferring personnel to and from the submerged vessel; air intake and exhaust space; and spaces for supplying fuel and services to the vessel.

With the vessel submerged in a body of water and the upper end of the snorkel tube free-floating, the tube is at an inclined angle with respect to the surface of the water. At a point just below the water surface, the snorkel tube is bent so that it projects upward in an approximately vertical direction. The lower part of the upper portion of the snorkel tube is fitted with nonbuoyant streamlined plate covers to minimize wave slap. For transferring personnel and landing supplies for the dredge, a landing cage having three platforms is pivotally carried by the upper portion of the snorkel tube. In addition, a crane is carried by the snorkel tube for transferring supplies and spare and repair parts to the dredge.

In the drawings:

FIGURE 1 is a perspective view of a submarine dredge provided in accordance with a preferred embodiment of the present invention, the dredge body being illustrated in submerged position for digging a trench along the bottom of a body of water;

nitecl States Patent C) 331,892 Fatented Mar. 28, 1967 ice FIGURE 2 is a view of the front end of the dredge body, but shows the snorkel tube broken off just above the universal connection to the dredge body;

FIGURE 3 is a perspective view of the upper portion of the snorkel tube;

FIGURE 4 is a sectional view of the upper portion of the snorkel tube, and is taken along the line 44 in FIG- URE 3;

FIGURE 5 is a sectional view of the lower end of the snorkel tube and universal joint connection to the submarine dredge and illustrating access to the dredge;

FIGURE 6 is a vertical sectional view illustrating the access door in the upper end of the snorkel tube above the water communicating with the platform; and

FIGURE 7 is a sectional view taken along lines 77 of FIGURE 6 illustrating the upper portion of the snorkel tube adjacent the platform and means for running the power and water lines therethrough adjacent the platform access door.

Referring to FIGURE 1, the submarine dredge comprises a hollow cylindrical body 11, a hollow snorkel tube 12, four tractor drive means 13 for propelling the dredge, and trenching equipment 16 for digging a furrow 17 at the bottom of a body of water having a surface 18. A pair of exhaust tubes 21 and 22 extend laterally from respective ends of the body 11 for disposing mud, silt, etc. that has been dug up by the trenching equipment.

The hollow cylindrical body 11 contains a pair of

end sections

25 and 26 for ballasting the dredge. An intermediate section 27 houses: a dredge crew; controls; and diesel machinery for powering the tractor drive means 13 and other elements of the dredge that use power. The spread between the tractor drive means at opposite ends of the dredge body 11 is sufficiently large to stabilize the dredge body 11 against moments of force applied to the body by the snorkel tube 12.

The snorkel tube 12 extends from the body 11 along an incline relative to the water surface 18. The upper end of the tube 12 is free-floating above the water. The lower end of the tube 12 is connected to the center of the body 11 by a hollow universal joint 30. The snorkel tube 12 permits the dredge to breathe underwater.

At a point which is slightly below the water level 18, the snorkel tube 12 has a curved portion 31 which turns into an upper portion 32. Portion 32 extends out of the water in an approximately vertical direction. If the lower portion of the snorkel tube 12 has an assumed maximum angle of forty-five degrees inclination relative to the water surface 13 for a maximum operating depth of the dredge body 11, the upper portion 32 extends vertically approximately thirty-five feet above the water surface 18, for example. The top of the upper portion 32 is well above the crest of the highest wave.

The snorkel tube 12 has an outside diameter of approximately seven and one-half feet, for example. As is shown in FIGURE 4, the tube 12 contains divisions which form a rectangular housing 33 for a movable elevator cage 34 to transport personnel and supplies through the snorkel tube and the universal joint 30 to the hollow body 11 of the dredge. The throat of the curved portion 31 of the snorkel tube 12 is widened to permit easy run of the elevator cage 34.

At opposite sides of the housing 33, two

spaces

35 and 36 are used for air intake and exhaust, respectively, for the hollow dredge body 11. The air intake supplies fresh air to the diesel machinery and also is used for ventilation. Exhaust from the diesel machinery passes through the space 36.

At the other opposite sides of the housing 33, two

spaces

37 and 40 are provided, respectively. The space 37 is used for housing fuel supply lines or pipes, which are connected to the diesel machinery within the dredge body 11. The space 40 is used for housing lines or pipes to supply fresh water and electric power services.

The top of the upper portion 32 of the snorkel tube 12 is decked over, except for the openings for air intakes, exhausts, and the end connections of the pipes for supplying fuel and services. A watertight hatch 41 is fitted for access to the elevator cage 34. In addition, a crane 42 of approximately three ton capacity, for example, is fitted to the upper portion 32 of the snorkel tube for transferring spare and repair parts to the dredge by means of the elevator cage 34. The air exhaust space 35 is provided with a projecting stack above the top of tube 12 to prevent contamination of intake air.

As is shown in FIGURE 3, a landing cage 45 is pivoted to a pair of large support brackets 46. These brackets are rigidly attached to the upper portion 32 of the snorkel tube 12. A suitable bufier means, not shown, is employed between the cage 45 and the snorkel tube upper portion 32 to keep the cage from banging portion 32 as the cage sWings about an axis through the brackets 46.

The landing cage 45 has three platforms at different levels for transferring personnel and landing supplies to be transported by the elevator cage 34 to the hollow dredge body 11. Access to the air intake side of the snorkel tube upper portion 32 from the top platform of the landing cage 45 is accomplished by a watertight door 59 and by a movable ramp 47.

Referring to FIGURES 6 and 7 the ramp 47 extends into the upper portion 32 of the snorkel adjacent the forward end of the elevator cage 34. The inlet area adjacent the door 50 is provided with vertical partitions 54 and horizontal partitions 55 extending between the periphcry of the tube and the vertical front wall or partition 56 of elevator cage housing 33 to form a space or an inlet chamber 40a between the platform and the elevator cage. The water pipe 57 and power lines or cables 58 extend through the restricted or reduced passages 59 defined by

partitions

54, 56 and the tube and do not interfere with access to the elevator cage from the platform.

The lower end of the tube 12 is connected to the dredge 11 by universal joint means generally indicated as 30 and best illustrated in FIGURE 5. Tube 12 is provided adjacent its lower end with yoke means including two divided and separated tubes or leg members 62. The hollow members 62 extend downwardly and outwardly from the lower single tube portion 12 and have a substantially lateral portion 63 joining their upper inner ends together. The portion 63 serves as the lower end of the elevator shaft and cage 34 rests thereon, as shown in FIGURE when it is in its lowermost position. One tube 62 is provided with a series of steps, guard rails and platforms or landings indicated generally as 64- to permit access of personnel to and from the dredge 11. The lower end of the water pipes 57 and power cables 58 also extend through this leg and down into the dredge proper.

The other leg or tube 62 is provided with an air intake conduit 65 and air exhaust conduit 65a in communication at their lower ends with the interior of dredge 11, and at their upper ends with their respective air intake and exhaust passages, spaces or

stacks

35 and 36.

Each leg 62 is provided with an inwardly and laterally extending hollow tubular section or member 66 as shown in FIGURE 5. The lateral legs 66 are provided with bearings 67 and wedge type sealing rings or stufiing glands 68 to provide a watertight seal with a T joint member 69. The bearings permit the legs 62 and snorkel tube 12 to rotate or pivot about and with respect to T member 69.

The T member 69 has a vertical leg 70 which is preferably ten feet in diameter mounted in bearings 71 to permit it to rotate or pivot about and with respect to the vertical tube or chamber '72 communicating with the interior of the dredge 11 and fixed by welding or the like thereto. The tube 72 is provided with proper sealing rings and gland means 74 to form a watertight joint. The

stufiing seal glands may be of a well known type used on ships wherein the propeller shaft extends through the hull, and be of a bleed type wherein water under pressure is continuously forced in an outward direction out of the hull, or in the present case out of the tube members.

As illustrated in FIGURES l and 3, a non-buoyant, streamlined pair of bowed

plates

51 and 52 are fitted around the snorkel tube upper portion 32. The

plates

51 and 52 are joined at their ends to form narrow fore and aft edges on opposite sides of the portion 32 for minimizlng wave slap. The

plates

51 and 52 extend from about five feet below to ten feet above the surface 18 of the water.

With the bottom end of the snorkel tube 12 held down by the universal connection to the submerged dredge body 11, the snorkel tube finds its own level when the moment of snorkel buoyancy equals the moment of its own weight about the universal joint 30. The upper end portion 32 of the snorkel tube 12 provides reserve buoyancy. In one design for the snorkel tube 12, at a maximum submerged depth for the dredge body 11 the snorkel tube 12 is inclined at an angle of forty-five degrees at a moment when balance is achieved between buoyancy and snorkel tube weight. Through a range of different water depths resulting in varying inclinations of the main snorkel body, the top end of the snorkel tube always floats close to the same waterline with buoyancy and weight moments balancing out.

If the dredge is operated through a range of water depths where the lower end of the snorkel tube 12 (at the universal joint 30) changes in depth from a maximum of one hundred fifty feet to a minimum of thirty feet, for example, the top of the snorkel tube upper portion 32 moves from thirty-five feet above water for the maximum depth to approximately twenty-nine feet above water for the minimum depth. The upper portion 32 makes a corresponding change from its vertical position to a position that is inclined by approximately thirty degrees with respect to the vertical.

Through the universal joint 30, the snorkel tube 12 will turn into a position where no turning moment is exerted on the dredge body 11. In other words, the snorkel tube 12 always assumes a position of least resistance in line with wind and wave and/or current.

The diameter of the snorkel tube 12 is relatively small. Therefore, the tube 12 offers a minimum resistance to the current in the body or channel of water. The

streamlined plates

51 and 52 about the waterline of the upper portion 32 of the snorkel tube 12 minimize the resistance of the snorkel tube 12 against wind and wave slap. Furthermore, because of the relatively small diameter of the snorkel tube 12, change of incline of the tube due to wave action will be minor.

The dredge body 11 must be weighted down sufiiciently to overcome dredge upsetting forces at the universal joint 30 which are caused by current, wind and waves acting upon the snorkel tube 12. If the bottom of the body of water in which the dredge is to operate is too soft for the required dredge weight, the dredge trenching equipment can be modified to cover a few feet on each side of the tractor drive means 13 at opposite ends of the dredge body 11. Top layers of soft bottom would be dredged away in front of the dredge tracks. Therefore, the weight or the bearing pressure of the dredge can be considerable without bogging down the dredge.

In operation of the dredge, personnel are landed on one of the platforms of the landing cage 45 by a boat, not shown, which can leave the dredging area without interrupting the operation of the dredge. The personnel pass through the door 50 in the snorkel tube upper portion 32, close the door, and are transported to the dredge body 11 by the elevator cage 34.

The diesel machinery is manned and controlled by the personnel to power the tractors 13 for propelling the dredge body 11 along the bottom of the water. As the dredge is propelled, the trenching equipment 16 digs a deep furrow 17. As the furrow is dug, mud and silt is disposed of laterally from the dredge body 11 by the tubes 21. The dredge is operated safely and efficiently even though the weather above water might be extremely bad, the body of water might be very rough, or the water might vary greatly in depth. Moreover, no floating power supply vessel is required to be anchored in the vicinity of the dredge.

The dredge equipment is preferably diesel hydraulic with a revolving cutter.

The dredge will be steered by a sonar beacon system, where a hydrophone is mounted at each side of the dredge, receiving signals from a sonar buoy. From the difference in time between receipt of the sound wave at each hydrophone, the angle of deviation between the vehicles direction of travel and the bearing to the sonar beacon can be calculated. When on course there is no time difference, and the vehicle is heading for the beacon.

Although the above-described embodiment, the words of description, and the drawings refer particularly to a preferred form of the present invention, it is apparent that various changes could be made without departing from the scope and spirit of the invention. Therefore, it is understood that the invention is limited solely by the scope of the accompanying claims.

What is claimed is:

1. Apparatus for gaining access to a sub-merged vessel comprising a snorkel tube which has at one end a hollow upper portion elongated in the upward direction and being normally free of connection with a vessel, and another end that is adapted to be secured to the submerged vessel; a universal joint for connecting the other end of said tube to the submerged vessel; and passageway means through said tube and said universal joint for communieating between said one end of said snorkel tube and said submerged vessel, and said hollow upper portion having a height such that it supplies enough buoyancy to support itself and counterbalance the forces tending to lower the upper part of the snorkel tube.

2. Apparatus according to claim 1, wherein said snorkel tube has a first portion that is adapted to extend from said joint on an incline relative to the surface of said water, said upper portion connected at an angle with said first portion at a point just below the surface of water so that said upper portion extends upward from the surface of said water.

3. Apparatus according to claim 2, further including a non-buoyant, streamlined bow-shaped plates attached at the waterline to the upper portion of said sn'orkel tube for minimizing wave slap.

4. Apparatus according to claim 1, further including a landing cage, means for pivotally supporting in a vertical plane said cage upon said snorkel tube, said cage having a plurality of platforms at different levels for receiving personnel and supplies.

5. Apparatus according to claim 1, further including a crane, and means for sup-porting said crane upon said snorkel tube for transferring supplies to said tube.

6. In combination, a hollow body which is adapted to be submerged in water; a hollow snorkel tube which has one end that is adapted to float freely above water; a hollow universal joint for permanently connecting the other end of said snorkel tube to said hollow body, said upper end being upwardly elongated and being normally free of connection with a vessel so as'to respond to wave action in heave only in cooperation with the other parts 6 of said snorkel tube and the universal joint; and an e1evator which is adapted to travel through said snorkel tube and said universal joint for transporting personnel between the floating end of said snorkel tube and the interior of said hollow body.

7. The combination set forth in claim 6, further including a landing cage attached to the free-floating end of said snorkel tube, said cage having a plurality of platforms at dilferent levels; and a watertight door in said snorkel tube for access to the tube from the top one of said platforms.

8. In combination, a hollow body which is adapted to be submerged in water; a hollow snorkel tube which has one end that is adapted to float freely above water; a hollow universal joint for permanently connecting the other end of said snorkel tube to said hollow body, said upper end being upwardly elongated and being normally free of connection with a vessel so as to respond to wave action in heave only in cooperation with the other parts of said snorkel tube and the universal joint; and nonbuoyant streamlined bow-shaped plates attached at the waterline to said snorkel tube at the free-floating end of said tube for minimizing wave slap.

9. A submarine dredge comprising a hollow submersible body, said body being divided into compartments for housing personnel, machinery and a source of power for driving the body along the bottom of a body of water to dig a trench; a hollow snorkel tube extending from said body on an incline relative to the surface of said body of water, the upper end of said snorkel tube being free-floating upon the Water; a hollow universal joint for permanently connecting the lower end of said snorkel tube to said body for transferring personnel from said snorkel tube to said submersible body, said upper end being upwardly elongated and being normally free of connection with a vessel so as to respond to wave action in heave only in cooperation with the other parts of said snorkel tube and the universal joint, the upper portion of said snorkel tube being bent at a point slightly below the surface of said water so that said upper portion extends nearly vertically from said water at a moment when the remaining portion of said snorkel tube is inclined by an angle of forty-five degrees relative to the surface of said water; a landing cage; and means for supporting said cage in hinged relationship upon said upper portion of said snorkel tube.

10. A submarine dredge as set forth in claim 9, further including partially submerged, non-buoyant means supported about said upper portion of said snorkel, said means comprising a pair of bowed plates that are joined at their ends to form narrow fore and aft edges on opposite sides of said snorkel tube for minimizing wave slap.

References Cited by the Examiner UNITED STATES PATENTS 813,935 2/1906 Avery 3756 867,984 10/1907 Lake 3756 1,379,928 5/1921 Lake 37 1,823,965 9/1931 Adler 37 1,963,996 6/1934 Lake. 2,390,557 12/1945 Scaife -1 ABRAHAM G. STONE, Primary Examiner.

WILLIAM A. SMITH, Examiner.

Claims

8. IN COMBINATION, A HOLLOW BODY WHICH IS ADAPTED TO BE SUBMERGED IN WATER; A HOLLOW SNORKEL TUBE WHICH HAS ONE END THAT IS ADAPTED TO FLOAT FREELY ABOVE WATER; A HOLLOW UNIVERSAL JOINT FOR PERMANENTLY CONNECTING THE OTHER END OF SAID SNORKEL TUBE TO SAID HOLLOW BODY, SAID UPPER END BEING UPWARDLY ELONGATED AND BEING NORMALLY FREE OF CONNECTION WITH A VESSEL SO AS TO RESPOND TO WAVE ACTION IN HEAVE ONLY IN COOPERATION WITH THE OTHER PARTS OF SAID SNORKEL TUBE AND THE UNIVERSAL JOINT; AND NONBUOYANT STREAMLINED BOW-SHAPED PLATES ATTACHED AT THE WATERLINE TO SAID SNORKEL TUBE AT THE FREE-FLOATING END OF SAID TUBE FOR MINIMIZING WAVE SLAP.
9. A SUBMARING DREDGE COMPRISING A HOLLOW SUBMERSIBLE BODY, SAID BODY BEING DIVIDED INTO COMPARTMENTS FOR HOUSING PERSONNEL, MACHINERY AND A SOURCE OF POWER FOR DRIVING THE BODY ALONG THE BOTTOM OF A BODY OF WATER TO DIG A TRENCH; A HOLLOW SNORKEL TUBE EXTENDING FROM SAID BODY ON AN INCLINE RELATIVE TO THE SURFACE OF SAID BODY OF WATER, THE UPPER END OF SAID SNORKEL TUBE BEING FREE-FLOATING UPON THE WATER; A HOLLOW UNIVERSAL JOINT FOR PERMANENTLY CONNECTING THE LOWER END OF SAID SNORKEL TUBE TO SAID BODY FOR TRANSFERRING PERSONNEL FROM SAID SNORKEL TUBE TO SAID SUBMERSIBLE BODY, SAID UPPER END BEING UPWARDLY ELONGATED AND BEING NORMALLY FREE OF CONNECTION WITH A VESSEL SO AS TO RESPOND TO WAVE ACTION IN HEAVE ONLY IN COOPERATION WITH THE OTHER PARTS OF SAID SNORKEL TUBE AND THE UNIVERSAL JOINT, THE UPPER PORTION OF SAID SNORKEL TUBE BEING BENT AT A POINT SLIGHTLY BELOW THE SURFACE OF SAID WATER SO THAT SAID UPPER PORTION EXTENDS NEARLY VERTICALLY FROM SAID WATER AT A MOMENT WHEN THE REMAINING PORTION OF SAID SNORKEL TUBE IS INCLINED BY AN ANGLE OF FORTY-FIVE DEGREES RELATIVE TO THE SURFACE OF SAID WATER; A LANDING CAGE; AND MEANS FOR SUPPORTING SAID CAGE IN HINGED RELATIONSHIP UPON SAID UPPER PORTION OF SAID SNORKEL TUBE.