The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

1 October, 191% THE MARINE REVIEW 69 ee =O "a Lock Nog 65 +139 Lo% Covered) ,..,,. BUHQNQS CFOSS ed) | Ord 7 TEAC KNOWS Wit me = 4 WES YI fs Ss PLAN VIEW OF PORTAL CRANE BUILT FOR THE AUSTRIAN LLOYD ARSENAL AT TRIESTE. AUSTRIA Trieste by the Skoda Works, Pilsen, ac- cording to Zeitschrift des Vereines Deutscher Ingenieure. The crane serves two docks parallel to each other, but separated by some distance, and con- nected with a cross-track over which the crane travels by means of. the special gear. The crane is driven by a 220-volt elec- tric motor. The current is conducted by a special sliding device and the usual cables. This arrangement insures long travels being made easily, and the traversing of the cross-track without re- peated adjustments of the cables. The crane, as constructed, is able, owing "to the cross-travel gear, to serve the two docks as well as the region between them, although the length of jib is only 44 feet. The electrical part of the crane was supplied by the Austrian Siemens- Schuckert Works: The upper part of the crane rests on eight runners, each two of which are supported on a bascule, as is also the entire crane as long as it is on one of the two longer tracks. For cross- traveling, double runners are fitted into the four feet of the portal which project through the upper bascule. The hoisting gear has a loose pulley and two pairs of spur wheels. The speed of descent is controlled by a braking switch. A spe- cial slipping clutch is fitted into the worm drive, which is used in common for the slewing and tipping gear. This clutch Protects the drive from shocks, especially at the end positions when tipping the jib. The crane can run unimpeded, over the crossings, in the longitudinal direc- tion, as at that spot the cross-rails are interrupted. The gaps are bridged over by swivel pieces, which when not in peration are parallel to the lengthwise tracks, 4 inches higher than the long tracks, which obviates the rims of the long-track "unners scraping on the long runners. For passing from the longitudinal to the cross track, the entire crane is raised at the point of crossing by raising the The cross-track is placed about. inner ends of the four bridges for the long-track runners, this lifting movement being continued until the swivel pieces can be laid in place. The crane is then lowered and set with the four double runners for transverse running resting on the transverse track. The bascules are held at their inner extremities by draw bars suspended from screw spindles. The female screw of the spindles are driven by a bevel gearing fitted on a platform on the upper part of the crane portal. The motor is coupled to a worm drive, to both ends of the spindle of which bevel wheels are fit- ted. The dimensions of the crane are: Lifting. capacity, tons... 4s... . ees sieeus 10 Adjustable: «sweep; feet... .< oi. oes os's ce 6 23-49 Height of center of rollers above upper edge Of rail; feebitccu eRe ee ia enue tees 4-71 Maximum lift, } feet ices oes ec cae dae ove 96 'Track: "of: portale fleets: oisecctiesstesca cleo Gis le os 13 Distance of extreme limit of counterweight fromthe: trunnions; feet ie. ss se eee. oc 10:0 Speed. of lift;. feet: pen minutes: *. sccs. 25. . 65 Motor for lifting, horsepower.............. 58 Motor for slewing and tipping, horsepower... 9.7 Time for tipping from lowest to highest posi- tion of: Jib; -mInutes# es vee ects scree sa 2.66 Speed Of 'travel, fect... ic. cies oe cee ose 49 Motor for running and raising the entire crane when shifting from one track to the other, Sa horsepower 491 Drilling Boiler Plates Drilling holes in boiler shell plates is often an expensive operation, due to the time consumed in handling the material. With the objéct of reducing | the drilling time to a minimum, the Van Dorn Electric Tool Co. Cleve- land, recently devised the equipment shown in the accompanying illustra- tion which is being used by the Puget Sound Machinery Depot, Seattle. Six of these machines are now in opera- tion at this plant. The device consists of an _ electric drill which is fed downward 'by means of a hydraulic cylinder, mounted di-. rectly above the drill. This device is controlled by a 4-way valve which ex- hausts underneath the plate to be drilled. Water is the medium used for operating and is supplied by the city mains at 85 pounds pressure to the square inch. All the extra equipment necessary is a truss which is carried over the top of the span. The drilling units traverse this span by means of trolley wheels,' so that several units can be used sim- ultaneously on one span. The material being drilled, as shown in the illustration, is boiler plate 17% inches thick, three thicknesses being drilled at one operation giving a total thickness of 4! inches. A high speed drill 1% inches in diameter is used and it is said that an average of eight minutes per hole, including shifting the machine from one point to another, has been successfully accomplished. Makes World Record Hog Island celebrated its first birth- day Aug. 5, 1919, by launching its forty-seventh ship and establishing a world's record for ship production. In the year, 367,775 deadweight tons were PORTABLE ELECTRIC DRILL EQUIPP ED WITH HYDRAULIC FEED FOR DRILLING BOILER SHELL PLATES