| US 7,476,083 B2 | ||
| Blade/disk dovetail backcut for blade/disk stress reduction (7FA+e, stage 1) | ||
| Daniel David Snook, Moore, S.C. (US); John Herbert Dimmick, III, Greenville, S.C. (US); Rachel Jane Obermeyer, West Chester, Ohio (US); Ariel Caesar Prepena Jacala, Simpsonville, S.C. (US); and Robert Craig Akin, Greer, S.C. (US) | ||
| Assigned to General Electric Company, Schenectady, N.Y. (US) | ||
| Filed on Jun. 28, 2006, as Appl. No. 11/476,095. | ||
| Application 11/476095 is a continuation of application No. PCT/US06/18468, filed on May 12, 2006. | ||
| Claims priority of provisional application 60/681169, filed on May 16, 2005. | ||
| Claims priority of provisional application 60/681455, filed on May 17, 2005. | ||
| Prior Publication US 2008/0260534 A1, Oct. 23, 2008 | ||
| This patent is subject to a terminal disclaimer. | ||
| Int. Cl. F01D 5/30 (2006.01) | ||
| U.S. Cl. 416—219R [416/248] | 12 Claims |
| 1. A method for reducing stress on at least one of a turbine disk and a turbine blade, wherein a plurality of turbine blades
are attachable to the disk, and wherein each of the turbine blades includes a blade dovetail engageable in a correspondingly-shaped
dovetail slot in the disk, the method comprising:
(a) determining a start point for a dovetail backcut relative to a datum line, the start point defining a length of the dovetail
backcut along a dovetail axis;
(b) determining a cut angle for the dovetail backcut; and
(c) removing material from at least one of the blade dovetail or the disk dovetail slot according to the start point and the
cut angle to form the dovetail backcut,
wherein the start point and the cut angle are optimized according to blade and disk geometry to maximize a balance between
stress reduction on the disk, stress reduction on the blade, a useful life of the turbine blades, and maintaining or improving
the aeromechanical behavior of the turbine blade,
wherein the datum line is positioned 2.470 inches from a forward face of the blade dovetail along a centerline of the dovetail
axis, and wherein step (a) is practiced such that the start point of the dovetail backcut is at least 1.945 inches in an aft
direction from the datum line.
|