AN IMPROVED SCREW STEERING AND PROPELLING DEVICE FOR STEAM VESSELS.

AN IMPROVED SCREW STEERING AND PROPELLING DEVICE FOR STEAM VESSELS.

A brief note in FIRE AND WATER last week called attention to the exhibition at Jersey City of the Kunstadter patent steering and propelling screw which is to be applied to the new fireboat for the city of Boston. We present herewith illustrations of this invention, which offer many features for the careful consideration of the officials of various cities now contemplating the building of such boats. The experience of fire departments having to cover extended water fronts bearing heavy values has been to so thoroughly demonstrate the usefulness of well equipped fire boats that a general and healthy movement in their favor has recently set in and bids fair to bear good fruit.

At this moment Brooklyn, Chicago, Cleveland and Buffalo have the newest built and equipped and, consequently, the most efficient boats of this class now in service. In design, ing the new boat for Boston, Mr. Cowles and his co-laborers have, however, devoted their best energies to the task of improving existing models and appliances. Upon the top of this comes New York’s appropriation of $75,000 for an additional and much needed boat. The amount of money set aside is a liberal one, and it is evident that it should pay for the highest type of vessel obtainable in every respect. Chief Nevins of Brooklyn also asks for another boat to supplement the work of the efficient, but overworked “Seth Low.” Milwaukee also evidently intends to have a boat, a committee of the city officials having recently been in Chicago, getting points on the subject, preparatory to taking action. Muskegon, Mich., too, warned by the recent serious blaze on the water front, is talking of building one, while the question of providing the Baltimore department with a suitable vessel for the protection of her wharves and warehouses will, we understand, be settled by the incoming city council which.it is announced, will make an appropriation for the construction of such a craft, to be “the largest and most powerful in the country.” The chief engineer of Pittsburgh’s Fire Department, too, says that he needs a boat to take care of much valuable property along the river front, which, in case of fire, his land engines could not properly protect. Altogether the chances for the building of some half dozen new fire boats within the next year or so are very good, and the inventive genius of the men who have given their attention to the improvement of such special apparatus should be correspondingly stimulated and fittingly recognized.

In illustrating and describing the double-ended screw ferryboat, Bergen, in our issue of last week, we suggested that the question of adapting this scheme in some modified form to a fire boat might be worth looking into. We are now informed that this Kunstadter swiveled screw can be arranged for double-end work, and that its inventor considers that it would produce exceptionally good results when so placed.

The illustration, fig. I, represents the ordinary propeller connected with the Kunstadter patent rudder screw, which, in this case, is mounted abaft the rudder, although it may be also fitted within the blade of the latter. The shaft of this rudder screw is carried by the rudder framework and motion is conveyed to it by a peculiarly constructed universal joint, by which it is connected with the main shaft, causing the rudder screw to revolve, and yet allowing the rudder to move freely to any required angle. Figure 2 gives the patent steering and propelling screw alone, in this instance fitted within the blade of the rudder. The peculiar swivel or joint by which it is connected with the shaft, either with or without the usual main propelling screw, is clearly shown and its workings will be readily understood.

This device has been put upon a number of European steam vessels during the past few years and, according to English journals, has worked well, both in rough and smooth water. As far as we are concerned on this side of the ocean, a favorable report was made in 1885 by a board of United States naval engineers,consisting of Chief Engineers Theo. Zeller, Geo. W. Magee and Geo. P. Hunt, upon the appliance as experimented with on the United States steamer Nina. Some extracts from this report read in effect, as follows :

KUNSTADTER SWIVELED SCREW. FIG. 1.

“ All attempts to steer the Nina, when backing with the large screw alone, prove completely abortive, though made in smooth water and light breezes. The position of the rudder in these cases seemed to produce absolutely no result, and the effect was the same whether the rudder was in the line of the keel or made any angle with it up to 45 degrees, and on either side. The vessel, in fact, backed just the same as though there was no rudder, going sometimes for a minute or more in nearly a straight line, and then falling off to starboard or to port for another minute or more, then continuing again in nearly a straight line or falling off in the opposite direction ; and all this no matter at what angle the rudder was placed, or whether it remained fixed, or was constantly moved in the attempt to control the course. There was no difficulty in promptly handling the rudder when backing at any speed, the proper mechanism having been previously arra’ ged aft for that purpose, or of holding the rudder in any desired position for any length of time. The difficulty was that the rudder seemed absolutely without effect in any position, the course of the vessel being determined by conditions extraneous to itself. Nor did this result seem to be affected by employing different speeds of engine ; it was the same at all speeds [ and the vessel as often fell off the straight course in a direction contrary to what she should have done in view of the position of the rudder as in conformity with that position. She was as likely to turn to starboard when the rudder was placed for turning her to port, and vice versa. The only conclusion to draw from many attempts under various conditions, was that, in backing. the rudder was simply inoperative. Of course, under the above conditions, the vessel could not be turned to either starboard or port by the rudder in backing, when the large screw was used alone. With the small or Kunstadter screw in use, it was possible, by careful watching, skillful judgment, and quick handling of the helm, to back the vessel in a straight line. * * * A critical examination was made of the universal joint of the Nina, after the long and severe service of the experiments. It was found intact, in perfect order, and with the tool marks on the wearing surfaces of the pins and jaws still uneflfaced. The use of the Kunstadter system of steering can be recommended for all screw steamers, merchant as well as naval, as it gives them the power to avoid collisions, and to thread narrow and tortuous channels, very much better than the ordinary rudder system of steering ; a also enables them to keep head to wind without steerage way, in fact with the vessel drilling before the wind, and her position can be perfectly commanded under all circumstances, for she can be manoeuvred promptly by the Kunstadter system, even while anchored. These are advantages not possessed in any degree by the rudder, because, before it can exert any effect, the vessel must have forward motion through the water. The swiveling screw, on the contrary, by being thrown over to starboard or to port, can exert a powerful turning effect upon the vessel when she Is held at rest. * * *”

KUNSTADTER SWIVELED SCREW. FIG. 2.

The claims pul forward by the inventor of this device are :

1. It enables a vessel to turn quickly and in a small space.

2. The ordinary rudder acts by resistance, and only while the vessel is in motion. The patent rudder screw is a motive power in turning the hull the moment the shaft revolves and before the ship attains the speed necessary to bring the ordinary rudder into play, thus dispensing with steam tugs and warping hawsers when docking.

3. One of the most important properties of the Kunstadter device is that the moment the engine Is stopped and reversed and the helm put to starboard or port, the vessel is powerfully drawn by the rudder screw in the required direction, during the time in which the way is being taken off and motion astern attained. The ordinary rudder is inoperative during this time, and these helpless minutes are the fruitful source of disaster to life and property in case of collision, icebergs, or going ashore.

4. In small vessels, such as steam launches, yachts, tugs, etc., the rudder screw alone, either Inside or aft of the rudder can be made a sufficient propelling screw.

5. The rudder screw picks np the slip of the main screw and so increases the speed, without a relative increased cost,

6. It is simple, inexpensive, durable, and not liable to get out of order, and can be readily fitted to any vessel now in existence or building.

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