US930907A

US930907A - Turbine blade and vane.

Info

Publication number: US930907A
Application number: US35040607A
Authority: US
Inventors: George Westinghouse
Original assignee: Individual
Current assignee: Individual
Priority date: 1907-01-02
Filing date: 1907-01-02
Publication date: 1909-08-10
Anticipated expiration: 1926-08-10

Description

G. WESTINGHOUSE. TURBINE BLADE AND VANE. APPLICATION FILED JAN. 2, 1907.

, Patented Aug. 10, 1909.

GEORGE WESTINGHOUSE, OF PITTSBURG, PENNSYLVANIA;

TURBINE BLADE A ND YANE To all whom it may concern:

Be it known that I, GEORGE WnsrrnenoU'sE, acitizen of the United States, and a resident of Pittsburg, in the county of Allegheny and State of Pennsylvania, have made a new and useful Inventionin Turbine Blades and Vanes, of which the following is a specification.

'This invention relates to elastic fluid turbines.

It has been found inpraotice that the ro-' tors and stators of elastic'fluid turbines are liable to, and do distort under certain operating conditions. It is essential to the efficiency of such machines to have the clear ances betweenthe relatively moving parts (that is, the clearances between the tip ends of the blades and the stator oncasing and the tips of the vanes and small, and to overcome the troubles which arise from small clearances and said distortions, hasbeen an object of this invention. I am aware that numerous attempts to this end have been made,but with all of them with which I am familiar fluid eddies resulting from the schemes utilized rendered the same impracticable.

A further object of this invention is to produce a turbine blade or vane which throughout its entire length presents to the working fluid the proper surface contour, and

the free end or tip of which, when collision between it and the surface element to which it stands adjacent occurs, may be readily. worn away in a predetermined amount whereby the remainder of the blade or vane will be uninjured and safe clearances at tained.

These and'other obj ects' I attain by means of the blades and vanes illustrated in the accompanying drawings forming apart of this application, and throu hout which like elements are denoted by ike characters.

In the drawings,'Figure 1 is afragmentary view of a portion of a turbine stator carrying two, annular rows of vanes and of a turbine rotpr carrying two rows ofblades alternating with said vanes; Fig. 2 is a view. in

perspective of a portion of a turbine blade or vane as the case may be, constructed in accordance withv this invention; Fig. 3 isan end view of a turbine blade or vane, as. .the case may be, constructed in accordance with this invention; and Fig. 4 1s a partial sectional view taken alongthe line A-'A of Fig. 3.

g The stator vanes 5, which may be secured Specification of Letters Patent. Application filed January 2, 1907. Serial a. 350,406.

jecting rim,

thus sheathing the projecting rim to Patented Aug. 10, 1909.

to the stator in anydesired manner, errtend to within close proximity of the rotor in order to maintain the small clearances desirable,. while the rotor blades 6, which may be secured to the rotor in any desired manner,

extend to within the same distance of the stator.

In order to present to the working fluid the proper surface contour the entire length, each blade and vane is properly formed of two parts; a core portion, which is preferably of steel, and anarmor or sheath, preferably of copper, which extends beyond the core portion, forming a pro ecting rim which lies in the planes of the blade faces and forms a hollow tip, which presents to the working fluid a working surface of the same contour as the blade proper. The rowhioh is of less cross sectional area than the major portion of the blade, may be readily worn away to the end of the major portion of the blade if COlllSlOIl tween it and the adjacent occurs.

In order to protect the blade proper against the erosive and corrosive effect of the fluid encountered, it is preferable to sheath the same with an armor of copper or some other metal equally as efficient as a protector. By the blade with a metal softer than the core portion, I am enabled to. form the tip end of tne blade same soft metal, tl us providing a wearing ti which will be as effective-1n exp'anding t e working fluid and abstracting the energy therefrom as though formed of the same metal as the core portion, but more effective as a weari tip.

Blades and vanes constructed in accordance with this invention are preferably formed by welding a copper envelop or sheath to a steel core, after which the whole is drawn to the proper cross section. Each blade then consists of a core portion 7 and a protect ve armor or sheath 8. After the blade strips are thus formed they are out into the proper lengths and the individual blades and vanes are then tip immersed in a suitable acid bath (such as sulphuric acid) whereby the ,core is attacked and removed in a predetermined amount, leaving a projecting rim of the sheathing or armor metal. acid for the bath, of course, will be chosen wh ch Wlll attack the core portion without touching the sheath 6r armor and the acid,- of course, may

be varied to suit the different metals used.

In Fig. 1, one blade and one vane is out throughout element to which it stands away near its outer end to illustrate the positions of the several parts of the structure.

In accordance with the provisions of the patent statutes, I have described the pram ciple of 0 eration of my invention, together with the V resent the best embodiment thereof, but I desire to have it understood that the device shown is only illustrative and that the invention can be carried outby other means.

What I claim is; 1. A sheathed turbine blade or vane, the

sheath of which projects beyond the sheathed portion'at one end of the b ads or vane. 2. A turbine blade or vane formed of a core and a protective cover or envelo which "projects beyond the core at one enr of the ade. 2. .A turbine blade or vane formed of metallic core and a metallic armor welded thereto and which projects beyond the core at one end of the blade.

4. Aturbine blade or vane formed of a metallic core and a metallic armor welded thereto and which projects in the planes of the blade or vane faces beyond one end of the blade or vane.

5. In-a turbine, alternate annular rows of moving blades and stationary vanes, the blades and vanes of which rows extend to -Within close proximity of the stator and rotor respectively; the free ends of each evice which 1 now consider to rep-- 7'. A. turbine blade or vane provided at one end with a wearing tip welded thereto...

8. A bladeor vane provided with a tip portion of metal softer than the major portion of the blade or vane.

9. A turbine blade or vane provided with a tip portion of metal softer than the major portion of the blade or vane and presenting to the working fluid working faces of sub- I stantially the same contour as the blade or vane.

10. A turbine blade or vane provided with a wearing tip of soft metal.

11. A turbine blade or vane provided with a soft metal tip welded thereto.

In testimony whereof, I have hereunto subscribed my name this 29th day of l )ecember, 1906.

GEO. wns'rrnenousn.

lYitnesscs CnAnLEs W. MoG-nnn, JNo. S. GREEN.