Chapter 4- PREVENTIVE AND CORRECTIVE DAMAGE CONTROL 



11.359 

 Figure 4-5.— Tandem connections for 

 submersible pumps. 



type; it is driven by a water-cooled gasoline 

 engine of special design. The pump delivers 

 500 gallons per minute at 100 pounds per square 

 inch pressure, with a suction lift of 16 feet. 

 The capacity may be increased by decreasing 

 the discharge pressure. 



The P-250 pump, which is similar to the 

 P-500 pump except for capacity, is scheduled 

 to replace the P-500 pump aboard ship. A P-250 

 pump is shown in figure 4-6. 



In order to estimate the number of pumps 

 required to handle a flooding situation, it is 

 necessary to consider the amount and location 

 of the water to be removed, the capacity and 

 availability of the installed drainage systems, 

 and the capacity of the available portable pumps. 

 It is also necessary to know whether the leaks 

 are completely plugged, partially plugged, or 

 not plugged at all— in short, it is necessary to 



know how much water is coming in while water 

 is being pumped out. 



REPAIR OF STRUCTURAL DAMAGE 



The kinds of damage that may have to be 

 repaired while a ship is still in the battle area 

 include holes above and below the waterline; 

 cracks in steel plating; punctured, weakened, 

 or distorted bulkheads; warped or sprung doors 

 and hatches; weakened or ruptured beams, sup- 

 ports, and other strength members; ruptured or 

 weakened decks; ruptured or cracked piping; 

 severed electrical cables; broken or distorted 

 foundations under machinery; broken or pierced 

 machinery units; and a wide variety of miscel- 

 laneous wreckage that may interfere with the 

 functioning of the ship. 



One of the most important things to remem- 

 ber in connection with the repair of structural 

 damage is that a ship can sink just as easily 

 from a series of insignificant- looking small 

 holes as it can from one larger and more 

 dramatic-looking hole. A natural enough tend- 

 ency—and one which can lead to the sinking 

 of a ship— is to attack the large, obvious damage 

 first and to overlook the smaller holes through 

 interior bulkheads. Men sometimes waste hours 

 trying to patch large holes in already flooded 

 compartments, disregarding the smaller holes 

 through which progressive flooding is gradually 

 taking place. In many situations, it would be 

 better to concentrate on the smaller interior 

 holes; as a rule, the really large holes in the 

 underwater hull cannot be repaired anyway until 

 the ship is drydocked. 



Holes in the hull at or just above the water- 

 line should be given immediate attention. Al- 

 though holes in this location may appear to be 

 relatively harmless, they are actually extremely 

 hazardous. As the ship rolls or loses buoyancy, 

 the holes become submerged and admit water 

 at a level that is dangerously high above the 

 ship's center of gravity. 



The methods and materials used to repair 

 holes above the waterline are also used, for 

 the most part, for the repair of underwater 

 holes. The greatest difficulty encountered in 

 repairing underwater damage is usually the 

 inaccessibility of the damage. If an inboard 

 compartment is flooded, opening doors or 

 hatches to get to the damage would result in 

 further flooding of other compartments. In such 

 a case, it is usually necessary to send a man 

 wearing a shallow-water diving apparatus down 



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