Патент USA US2410201код для вставки
oct. 29, 194e. ' J_ F, CORBY ` ' 2,410,201 PLATE '-'STEEL CASING JOINT FOR ROTARY HYDRÀULÍIÍC-MÀGHINESv Filed April 26,1944 _Il N / . y2,410,201 Patented Óct. 29, y:19426K ,410,291.1 ., , G JOINT?FSI?3 NS „Corby,. HYDRAULIC Philadelphiaïî Pa., `assign otiye Works', ‘afcòrporatión Applicatiorinpm c, 194.4;y »Seria l No states-È' i 'Y " D . ' " ~ 'zel-assi (ci.44V This invention relates to plate steel volute casings for rotary hydraulic machines such as hydraulic turbines and pumps. 3 and at the same time place the rivets under double shear, I machine a groove 9 and a ' vanes small rib I0 circularly around the stay vane ring preferably on the uppermost and lowermost sur of the respective walls and the plate metal heads considerable diiiâculty is frequently experi CII faces Il of the casing is ñtted against the rib I0. A enced in obtaining proper flow velocity conditions rivet strap I2 is anchored to the ring by being within the casing primarily because of the in provided with a circular key I3 which fits into ability to have'certain portions of the plate steel the keyway 9.' Rivets I4 .extend through the stay casing _of sufficiently small radius of curvature at ring, plate and strap I2 and are placed in the points where the casing joins the usual stay lo vane double shear by reason of the strap I2 being vane ring especially at the small cross-sections of keyed to and forming in elîect a rigid part of the casing. This difficulty has heretofore arisen the stay ring structure itself. Hence, when the because of the necessity to provide an extended casing is subjected to internal water pressure so When volute casings are used under certain straight portion of the plate steel casing adja cent the stay vane ring in order toemploy usual 4riveted butt straps on each side of the 'casing joint and thereby place the rivets in double shear. that the plate I I is placed under tension the load will be transmitted directly to the stay ring through the rivets and to the plate I2 which in turn transmits the load to key I3 and thence to the stay ring. LIn this manner it is possible to improved combination of elements whereby a eliminate the excessive space that is normally 20 plate steel casing of a rotary hydraulic machine required to produce a double strap riveted joint may have a relatively small radius ofcurvature which has been necessary in order to place the adjacent the stay vane ring and particularly at rivets in double shear. Hence, with my improved the small cross-sections of the casing, in the case arrangement, it is possible to obtain more ideal of a volute, where the problem of making small 25 flow conditions within the casing particularly at radii of curvature is particularly acute. the'small cross-section because of the ability to Another object is to provide an improved com start a small radius of casing curvature close to bination of elements for obtaining small radii of the stay vanes. curvature, of a plate steel casing,.adjacent the The modification shown in Fig. 3 allows the stay vane ring and still cause the rivets to’be in 30 curvature of the casing to start very abruptly ad double shear. jacent the stay vane ring I1, this being accom-V » Other objects'and advantages will be more ap plished by providing a plate metal supporting parent to those skilled in the art from the fol » surface I8 of suliìcient depth on the stay ring lowing description of the accompanying drawing so that the plate metal casing 20 extends to a in which: ` ^ ' midway of the radial depth of 35 Ypoint 2| about Itis an object of my invention to provide an Fig. 1 is a partial sectional view through a cas ing and a portion of a hydraulic turbine; Fig. 2 is an- enlarged fragmentary sectional view V the guide vane I9. To provide a ñrm anchor for the'rivet strap 22 it extends inwardly over the whole of the upper end of the stay vane ring with a substantial flanged end of key 23 which Figs. 3 and 4 areV enlarged sectional views overlaps the inner edge 24 of the stay vane ring. 40 showing modiñed forms of arrangements by plac Rivets 25 secure the component elements to - ing the rivets in double shear. gether and the rivets are placed in double shear The particular embodiments of the invention of the casing joint shown inFig. 1; and ' - disclosed herein have been applied for purposes by virtue ofplate 22 being anchored at 23 and 24. The lianged end 23 of the strap plate is of illustration to a Francis type hydraulic turbine including a runner I, adjustable guide vanes 2 45 fitted within the corner 26 of the head cover -21 well-known in the art. f and stay vanes 3 which are secured at their upper In the modification shown in Fig. 4, the cas and lowerends to flow guidingportions 4 and 5 ing plate 30 is placed on the inside of the stay extending as a'surface of revolution around the ring 3I while a rivet strap 32 has a key 33 seated runner axis. The stay vanes and portions 4 and 5’are usually cast'integrally from a stay 'vane 50 in a circular keyway of the stay vane ring. The _ rivets 34 will be placed in double shear by reason ring. A plate steel casing 6, generally of volute of the inside strap being anchored to the stay form, well-known in the art, is usually riveted to the edges of the stay ringk elements 4 and 5. In From the foregoing disclosure of the several` order to allow the casing to start its curvature 'I as close as possible to the edge 8 of the guide 55 modifications, it is seen that I have provided an ring. ' ` ' 2,410,201 3 4 improved arrangement of overlapping casing and stay ring elements whereby the casing plates may overlapping one side of said plate steel casing near its edge portion, a rivet strap overlying the other side of the Vplate steel casing, and means for anchoring said strap to the stay vane ring be curved very closely to the stay vanes 8 thereby to permit desirable velocity and ñow conditions to be obtained While at the same time insuring by a direct abutting contact with a transverse maximum structural strength to thesjoints be surface on said ring whereby rivets extending tween the Acasing`v` and stay vanev ring. It is, =of course, to be understood that the keyed straps through said strapy plate and ring will be placed in doubleshear to provide'necessary strength and will be formed in segmental lengths. to allow curvature of the casing at its small sec It will of course be understood that various tions to start adjacent the stay ring thereby to changes in details of construction and arrangee ment of parts may be made by those skilled in the art Without departing from the spirit of the invention as set forth in the appended c1aims.,. I claim: . ‘ ' I obtain more desirable flow conditions through the volute casing. 2. The combination set forth in claim 1 further characterized in that a head cover is provided with a recess to receive said stay vane ring, and 1. A rotary hydraulic apparatus comprising, in said ring has an annular ledge at its innermost combination, a stay vane ring and .a volute plate ‘edge and the strap has a flanged portion seated steel casing therefor having certain small sec in saidvrecess and overlapping and engaging said tions that are relatively small compared to oth edge. " ì ers, said stay vane ring having a portion 20 JOSEPH F. CORBY.