DD-22 Paulding
Twenty-one Paulding (DD-22) class destroyers were laid down 1909-11 and commissioned 1910-12 making them the largest class of destroyers built for the U.S. Navy at the time. They were essentially Smith class destroyers which used oil-fired boilers rather than coal which resulted in a 14-ton decrease in displacement and resultant higher speed, achieving 32.8 knots on trials. The armament was simliar to that of the Smith (DD-17) class but with added torpedo armament.
The 950-ton class comprises destroyers numbered serially as high as 42 (the Jenkins). Vessels of this class had a high forecastle extending from the stem to a point just abaft the pilot house, where it breaks off to a low main deck which is extended to the stern. The high forecastle of these vessels plays an important part in their manoeuvring qualities; acting as a permanent jib, which, while helpful under some conditions, is a serious handicap under others. It must always be kept in mind and allowed for, its principal effect being, of course, to make it difficult to bring the vessel up to the wind. Caution must be used when such a vessel is run into a small harbor into which the wind is blowing and where it will be necessary to turn her within the harbor in order to get out. Under such conditions the ship may get beam to wind, and, lacking space to gather headway, refuse to turn into it, and may drift ashore broadside on. Several narrow escapes are on record resulting from failure to appreciate this feature.
In turning with a vessel of this type, it is desirable to turn in such a way as to take advantage of the jib effect instead of having to work against it. The effect of the wind upon the bow is particularly important in going alongside a dock. Destroyers of this class had a large after dead-wood, which resulted in greater steadiness of sea route but produced an excessively large turning circle, the tactical diameter being as great as one thousand yards with rudder angle of twenty degrees.
They served convoy escort and patrol duties during World War One. Thirteen of this class were transferred to the Coast Guard 1924-31 patrolling against rum runners in the Caribbean and serving other duties. A total of thirty-one Navy destroyers were lent to the Coast Guard for enforcing Prohibition. Adapting these vessels to service was thought to be less costly than building new ships. In the end the rehabilitation of the vessels became a saga in itself because of the exceedingly poor condition of many of these war-weary ships. In many instances it took nearly a year to bring the vessels up to seaworthiness. Additionally, these were by far the largest and most sophisticated vessels ever operated by the service and trained personnel were nearly nonexistent. As a result, Congress authorized hundreds of new enlistees. It was these inexperienced men that generally made up the destroyer crews.
These pre-World War I 742-ton "flivvers" were capable of over 25 knots, an advantage in the rum-chasing business. They, however, were easily outmaneuvered by smaller vessels. The destroyers' mission, therefore, was to picket the larger supply ships ("mother ships") and prevent them from off-loading their cargo onto the smaller, speedier contact boats that ran the liquor into shore. Returned to the Navy, they were sold for scrap 1934-35.
The first United States naval vessels to have turbines were the Scout Cruisers "Chester" (Parsons) and "Salem" (Curtis), which were contracted for in 1905 and completed in 1908. The first United States Destroyers fitted with turbines (Parsons) were the "Smith", "Lamson", "Preston", "Flusser" and "Reid", contracted for in 1907 and completed in 1909, and two Paulding-class destroyers, the "Sterett" and "Perkins" (Curtis) contracted for in 1908 and completed in 1910.
The Curtis type turbine is an efficient marine turbine, and trials brought out the fact that the consumption per brake horse-power per hour is fairly constant at both low and high speeds. This result is chiefly due to the fact that the steam, being admitted by hand-controlled nozzles, one or more of these can be shut off as required for reduced speed, thus eliminating the wire-drawing losses which occur when the main stop-valve requires to be partly closed to reduce the steam flow and shaft speed.
The Curtis turbine is of the compound impulse type, the compounding being for pressure and velocity. Generally described, the Curtis turbine may be said to represent a combination of the De-Laval and Parsons, as nozzles similar to the De-Laval type are arranged on the periphery of the wheels through which the steam is admitted to each stage, and fixed and moving blades similar to the Parsons type are arranged within the stages themselves.
Each stage consists of a set of expanding nozzles, and two or more rows of moving blades alternating with fixed blades. Between each stage is fixed a diaphragm with expanding nozzles. The total expansion of the steam, therefore, takes place in stages in the successive expanding nozzles, the kinetic energy developed at each expansion being absorbed as it passes through the successive moving and fixed blades of each stage.
It should be noticed that, being an impulse-type turbine, the steam falls considerably in pressure in the nozzles of each stage before acting on the moving blades inside the stages, and this fall of pressure results in increase of velocity, the kinetic energy thus liberated from potential energy acting solely to produce increase of steam speed. The revolutions can thus be kept down to bring out the efficiency of the propeller, which gives this type of turbine an advantage over the Parsons type, in which propeller efficiency is often sacrificed more or less for turbine efficiency.
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