US 3696773 A
A method of raising sunken ships comprising the filling of "lay-flat" plastic tubing having a uniformly, evenly spaced, longitudinally ribbed interior with compressed air while submerged. The plastic tubing is stored on a motor driven reel device, in the flat or collapsed state, and is then unwound within the hull of the sunken ship and simultaneously filled with compressed air.
Description (OCR text may contain errors)
United States Patent Morris 51 Oct. 10,1972
 METHOD FOR SALVAGE OF SUNKEN SHIPS  Inventor: Ross E. Morris, Vallejo, Calif.
 Assignee: The United States of America as represented by the Secretary of the Navy 22 Filed: Dec.23, 1970 21 Appl.No.: 100,945
 US. Cl. ..114/54  Int. Cl. ..B2ld 19/00  Field of Search ..9/316; 52/2; 114/20, 50, 52,
Primary ExaminerEdward A. Sroka AttorneyR. S. Sciascia and Charles D. B. Curry  ABSTRACT A method of raising sunken ships comprising the filling of lay-flat plastic tubing having a uniformly, evenly spaced, longitudinally ribbed interior with compressed air while submerged. The plastic tubing is stored on a motor driven reel device, in the flat or collapsed state, and is then unwound within the hull of  References Cited the sunken ship and simultaneously filled with com- UNlTED STATES PATENTS Pressed 2,857,078 10/ 1958 Wolfert ..9/3l6 4 Claims, 5 Drawing Figures COMPRESSED AIR 3 FROM SURFACE VESSEL PATENTED BI 10 I9 3.696, 773
sum 1 OF 2 COMPRESSED AIR 3 FROM SURFACE VESSEL INVENTOR ROSS E. MORRIS BY FlG 2 My 2 ATTORNEY PATENTEDnm 10 1912 3.696, 773
SHEET 2 0F 2 W T cw-An V I F |G 3 AIR SPACE R T h T 1 R R 'v.
RADIUS F INVENTORQ ROSS E. MORRIS 'FlG 5 ATTORNEY METHOD FOR SALVAGE OF SUNKEN SHIPS BACKGROUND OF THE INVENTION The present invention relates generally to the use of lay-flat plastic tubing as a flotation material and more particularly to a new method of using the plastic tubing with a longitudinally ribbed interior in its flat or collapsed state and filling the lay-flat tubing with compressed air to provide buoyancy. The flat plastic tubing is stored on a reel and is unwound within the hull and concurrently filled with compressed air.
There are generally two methods employed for raising sunken ships. The first utilized air-filled pontoons which support the vessel on cable slingsto provide buoyancy. The second utilizes compressed air to expel the water in the vessel to provide buoyancy. The drawback of the first procedure is the difficult rigging required. The objection of the second procedure is the need to seal all openings in the vessel to prevent the venting of the air. Recently a variation of the second employed a polyurethane foam to provide buoyancy. However, serious problems arise from this method when the operation is attempted at greater depths than 450 feet and at water temperature below 50 F.
SUMMARY OF INVENTION The new improved technique will eliminate the perplexities of the existing methods for raising sunken ships. The material is lay-flat tubing that is expanded by compressed air to create the buoyant medium. Moreover, there is theoretically no depth or seawater temperature limitations on this unique buoyant medium system. The inflated lay-flat tubing is a more efficient flotation material than foam, from the standpoints of weight per cubic foot, cost per cubic foot, and ease of removal from the refloated vessel. Additionally, there are no complex rigging problems involved with the use of flat plastic tubing.
Although tubings using a smooth inner surface may be used, such tubings are not as suitable for salvaging operations because the inflated floating tubing may tend to kink where the tubing abruptly changes direction in the flooded compartment. The kinks might prevent air from passing through the uninflated tubing when unreeling. To enable air to pass readily through kinked tubing, the tubing should have longitudinal ribs which will hold apart the opposing surfaces at the kink. Another benefit of the ribs is that they will prevent a crease from forming at the folds when the tubing is in its flat condition. This crease would weaken the tubing and cause it to rupture at a low pressure differential when inflated.
STATEMENTS OF THE OBJECT S OF THE INVENTION The major object of the invention is to provide a more suitable and efficient method for the salvage of sunken ships.
Another object of the invention is to provide a more suitable material to salvage sunken ships.
A more particular object of the invention is to provide a material which will eliminate the need for cleaning the interior of the hull of the refloated ship.
Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings wherein:
FIG. 1 is a simplified drawing of the method of filling a compartment in a sunken vessel with inflated plastic tubing;
FIG. 2 is a simplified drawing of a compartment in the sunken ship filled with inflated plastic tubing;
FIG. 3 is a simplified drawing illustrating a cross section of a typical ribbed tubing in the lay-flat condition;
FIG. 4 is a simplified drawing illustrating the cross section of a typical ribbed tubing in the expanded condition;
FIG. 5 is a simplified drawing illustrating an alternative method of filling a compartment in a sunken ship with inflated plastic tubing.
METHOD. DESCRIPTION OF THE PREFERRED EMBODIMENT(S).
Referring to FIG. 1, reel device 4 holding tubing 6 in the flat or collapsed state, hereafter referred to as layflat tubing, is supported by a platform deck 9 on the inside of hull 1. The open end of tubing 7 is connected to a vertical noule 8 at the end of injector pipe 5. Injector pipe 5 has a pressure regulator for maintaining the air pressure in the nozzle at a value of not more than 3 psi above the water pressure at the nozzle. Injector pipe 5 is connected by a hose to a service ship or barge on the surface. The walls of the inflated tubing are made sufficiently strong and rigid to bridge over small openings in the hull without rupturing and extruding. The tubing thus entraps the air and prevents it from leaking from the hull. The end opposite the quick disconnect 7 of the tubing 6 on the reel has been previously sealed so the air does not escape when the tubing is free of the reel. The end of the tubing 7a attached to end inflating pipe 7b quick disconnect is removed from the pipe and weighted so that it rests on the deck. This open end permits excess air pressure to escape. A convenient way to weighing the open end is to leave the tubing connected to a short pipe nipple or part of a quick-disconnect coupling 7a.
Referring to FIG. 2, air entering the tubing 12 causes it to become buoyant so that it rises in the water-filled compartment 11. The hull compartment 11 is illustrated as being almost full of inflated tubing 12. The weighted tubing 12 is open at one end 13 to prevent the tube from bursting as the vessel rises in the water as the ambient water pressure decreases.
TUBING CONSTRUCTION Referring to FIG. 3, wherein a series of relatively spaced inwardly projecting rib partitions (R) of the wall (W) of tubular structure (T) are spaced as shown. It should be noted that air space channels x are created when the ribbed tubing is in the layflat condition to enable air to pass readily through any kinked tubing. Again referring to FIG. 3, the evenly spaced longitudinal ribs (R) are used to enable air to pass readily through kinked tubing (T). These ribs (R) can be readily formed by using a suitably designed die when extruding the tubing. Another benefit of the ribs (R) are that they will prevent a crease from forming at the folds when tubing (T) is in its lay-flat condition. FIG.
4 shows a cross section of the inflated ribbed tubing (T). Material such as Polyethylene and Polypropylene, having densities in the range of 0.90 to 0.96, have been found to be a very effective flotation material. Both Polyethylene and Polypropylene have a positive buoyancy even before inflation. Moreover, high density Polyethylene and Polypropylene have tensile strength above 4,000 psi and are completely resistant to deterioration by seawater.
In FIG. 5 is schematically illustrated an alternative method for filling a compartment in a sunken ship with inflated plastic tubing. Referring to FIG. 5, the reel 16 of flattened tubing is set up outside the sunken vessel l4 and the tubing is fed between a series of parallel motor driven rollers 17 into the opening 18 in the side or. bottom of the vessel. It should be noted that the spacing between the parallel rollers should be adjustable so that the tubing remains flat until it reaches the location inside the vessel where expansion of the tubing is desired.
What is claimed is:
l. A method of raising sunken ships including a salvage ship air compressor injector pipe; said pipe comprising a valve, a quick disconnect and a portable reel containing a plurality of continuous rolled up internally ribbed lay-flat plastic tubing with a quick disconnect at one end and sealed at the other stored on said reel; the method comprising in combination the steps of:
a. placing said portable reel containing the plurality b. lowering said injector pipe into the entrance of the damaged area of said sunken ship;
c. attaching saidquick disconnect of said lay-flat plastic tubing to said injector pipe;
d. opening said valve of said injector to allow free flow of compressed air;
e. pumping compressed air from said compressor through said injector pipe and into said lay-flat plastic tubing while simultaneously unreeling said lay-flat plastic tubing into said hull of said damaged ship until each of said lay-flat plastic tubing is completely unreeled from said reel; and
f. disconnecting each of said tubing from said injector nozzle.
2. The method in claim 1 to wherein the air-pressure in the nozzle is compressed to a value of not more that 3 psi above the water pressure at the nozzle.
3. The method in claim 2 wherein the plastic tubing comprises an internally and longitudinally evenly spaced ribbed tubing, said plastic tubing being unreeled through parallel driven rollers into the opening in the side of damaged ship while compressed air from said salvage ship is pumped into said attached tubing.
4. The method of claim 1 wherein a plurality of continuously rolled up plastic tubes are unreeled into damaged area of the ship.