Engineering Wonders of the World
Volume I

38 ENGINEERING WONDERS OF THE WORLD. Fig. 11.—SEGMENT OF TURBINE BLADING READY FOR FIXING TO ROTOR. Fig. 12.—COMPLETE RING OF BLADING FOR ROTOR. {Photos, The. Wallsend Slipway and Engineering Company.) Mauretania, an arrangement of four screws was adopted. The machinery of the two last-named vessels consists of two high-pressure ahead turbines driving the wing shafts, and two low- pressure ahead turbines and two astern turbines connected to the two centre shafts. Since the turbine installations of the Lusitania and Mauretania, each indi- cating approximately power, divided about equally over the four screws, are by far the most powerful in the world, some further de- 70,000 horse- “ Lusitania’s ” and “Maure- tania’s” Tur= bines. tails concerning them may with advan- tage be given. Figs. 11 and 12 show the method adopted for fitting the blades to the Mauretania1 s turbine rotors. The blades were securely fixed by hand into slots prepared in the foundation ring by a special auto- matic tool, and formed into finished segments, the number of segments to form one complete ring being ten. Fig. 11 represents one segment ready for fitting to the rotor, while Fig. 12 shows a complete ring of blading. The segments when complete were fixed in the annular grooves prepared for their reception in the rotor, and in this way wing or outer shafts are each revolved by a low-pressure turbine. As the turbine cannot, on account of the arrange- Triple and ment of the blades, be re- Scre^Turbine versed’ sPecial high-pressure Vessels. reversing turbines, for use when the vessel has to go astern, are generally fitted on the shafts of tho low-pressure ahead turbines. In the largest war vessels, such as the battleships of the Dreadnought type and the armoured cruisers of the Invincible class, and in the Cunard express steamers Lusitania and a great many men could be employed on the numerous segments of blading, on the turbine casings, and on the rotors at the same time. The immense size of the turbine rotors of both vessels will be realized by reference to Fig. 14, which shows one of the low-pressure rotors fully bladed. These ro- tors were made of Whitworth fluid - compressed steel, and were machined out of solid ingots. The ingots used for the larger rotors each weighed 120 tons. The turbine casings, which were made of Turbine Rotors and Casings.