GB111153A - Improvements in or relating to Steam Turbines. - Google Patents

Abstract

111,153. Baumann, K. Nov. 14, 1916. Axial-flow type; casings; exhaust, disposing of.-Relates to axial-flow turbines having exhaust casings fitted with guides for outwardly deflecting the steam leaving the moving blades, and with internal guide-walls located in planes substantially parallel with the turbine shaft which divide the exhaust steam into segmental portions, and consists mainly in extending these internal guide-walls right across the exhaust blade area, and in shaping them so as to obtain compact and easy exhaust paths for the steam. The internal guide-walls 3, 4, which may be mounted in a removable frame 15, Fig. 6, extend across from the outer to the inner circumference of the exhaust area of the moving blades 2, and their upper portions are formed to substantially involute curves, the base circle from which such curves are described being preferably of less diameter than the diameter of the outer circumference of the exhaust blades 2 and occasionally less than that of the inner circumference thereof. The guide-walls may be extended by webs 5, 6, which strengthen the exhaust casing so that, if desired, the turbine may be supported from feet located at the ends of its exhaust casing only. as described in Specification 110,791. Additional division waits 8. 9 of helicoidal shape and a V- shaped portion 7 may be provided in the upper half of the exhaust casing, and walls 10, 11, 12, 13 in the lower half. with or without a transverse web 14. In a modification, the invention is shown applied to a multiple-exhaust turbine of the kind described in Specification 14053/15 having an exhaust casing similar to that described in Specification 105,933. A further modification relates to an exhaust casing located centrally between ahead and astern turbines. The number of guide-walls employed may vary from two upwards according to the size of the turbine. With exhaust casings. which are not symmetrical about the vertical axial plane, as shown for example in Figs. 25, 26, and 27 of Specification 105,933, the whole of the exhaust blade area may be divided up by the guidewalls into sections alike in shape. Other curves than involutes are indicated for the guide-walls. A portion only of the exhaust steam may be handled by the described casing, the other portion being led away by an exhaust casing of any suitable known type.