Gas turbine sealing band arrangement having an underlap seal
A sealing band arrangement for a gas turbine including first and second adjoining rotor disks each including a disk arm having a slot. The sealing band arrangement includes at least one first seal strip segment located within the slots, wherein the seal strip segment includes first and second ends. The sealing band arrangement also includes a tab section that extends from the first end in order to form an underlap seal with an adjacent second seal strip segment. The underlap seal enables a thickness of the first and second ends to be substantially equivalent to a thickness of the first seal strip segment in order to improve wear life of the seal strip segment. The sealing band arrangement further includes at least one wide portion formed in the first seal strip segment wherein the wide portion is wider than a remaining portion of the first seal strip segment.
1. A sealing band arrangement for a gas turbine, wherein the gas turbine includes first and second adjoining rotor disks each including a disk arm having a slot and wherein the disk arms are separated by a disk arm gap, comprising:
at least one first seal strip segment located within the slots, wherein the seal strip segment includes first and second ends;
at least one second strip segment adjacent to the first seal strip segment, the at least one second strip segment includes first and second ends; and
a tab section extending from a radially inner surface of the first seal strip segment to underneath a radially inner surface of the second seal strip segment so that an underlap seal with the second end of the adjacent second seal strip segment is formed; and
a plurality of wide portions formed in the first seal strip segment, wherein the plurality of wide portions are wider than a remaining portion of the first seal strip segment for limiting movement of the first seal strip segment within the slots wherein the plurality of wide portions are disposed only at the first and second ends of the first seal strip segment and at a center portion of the first seal strip segment,
wherein a thickness of the first and second ends of the at least one first seal strip segment is substantially equivalent to a thickness of the first seal strip segment, and
wherein a thickness of the first and second ends of the at least one second seal strip segment is substantially equivalent to a thickness of the second seal strip segment.
2. The sealing band arrangement according to claim 1 , wherein the first end of the at least one first seal strip segment is separated from the second seal strip segment by a seal strip gap and the tab section seals the seal strip gap.
3. The sealing band arrangement according to claim 1 , wherein the tab section is unistructurally formed with the first end.
4. The sealing band arrangement according to claim 1 , wherein the tab section is approximately 9.5 mm wide.
5. The sealing band arrangement according to claim 1 , wherein the first and second ends of the first seal strip segment are each approximately 2.7 mm thick.
6. The sealing band arrangement according to claim 1 , wherein the sealing band arrangement includes four seal strip segments.
7. The sealing band arrangement according to claim 1 , wherein the first and second seal strip segments each include an anti-rotation device.
8. The sealing band arrangement according to claim 1 , wherein the at least one wide portion is approximately 2 mm wider than the remaining portion of the first seal strip segment.