The Mechanical Handling and Storing of Material

232 THE MECHANICAL HANDLING OF MATERIAL two sections through the principal parts with the movable distributor d and the bend R of the ejector pipe. 1 he hydraulic ejector by Körting, of injector fame, is represented in Fig. 321, and shows distinct advances in the right direction. The Fig. 319. Hochstein’s Method for Dis- charging Ashes to Port or Star- board of a Vessel. ejector pipe b leads by a bend into the larger pipe c, which terminates at the ship’s bottom, with an alter- native side outlet under water at the side, as shown in dotted lines; d is a perforated plate to prevent dust, while e is an air inlet, which ensures that the water level is the same in the pipe c as outside. The following data are available in connection with this ejector: The water used was of a pressure of 180 lb. per square inch, and passed to the ejector through a 2j-in. pipe. The ejector used 3,300 gals, of water to eject 7 to 8 tons of ashes to a height of 13 to 14 ft. through a 4-in. pipe. Ejector Pipes.-—The bends in the ejector pipes, which are practically indispensable in all the foregoing installations, have been found to be sub- ject to enormous wear and tear, as, owing to the centrifugal force when negotiating bends, all the abrasion takes place on the one side and under the most adverse circumstances. The pipes have, therefore, been made with thicker metal on the side most affected, and also with renewable liners, as well as lined with glass, which is harder than ashes and so reduces the wear. There can be no doubt that, where possible, the ideal exit for he discharge of the ashes is vertically down through the ship’s bottom, as this method has the following distinct advantages. The discharge pipe is short and straight (without bends); it makes the passage of pipes through the bunkers and decks unnecessary; the condition of the weather is immaterial to the successful expulsion of the ashes, contrary to side delivery above the water line, as such installations have frequently to be fitted in duplicate, on the port and on the starboard side, as already mentioned, so as to enable the discharge of ashes to leeward in all weathers, and even then a head or following wind will cause the seas to carry the ashes back on to the deck, as well as into the stern tubes and sea suctions, and the ashes will cause scoring of the skin plating at and below the water line. Latest Developments.—With the advent of the recent types of battleships and cruisers with their powerful turbine engines, the question of the mechanical disposal of the now enormous quanti- ties of ashes has become a most important one. The non-inter- ference with the existing structural arrangements was a sine qua non. The Admiralty, while seeking a solution of the difficulty, experimented with an ejector used in the French Navy, with a discharge through the bottom of the ship, but it did not answer the requirements of the British Navy; the naval authorities, therefore, experimented in the same direction, and eventually produced a system by which the clinkers, ashes, and other refuse were first crushed Fig. 320. Details of the Principal Parts of Fig. 319, in Front and Side Views.