Steam generator tubesheet face machining apparatus
Abstract
Abstract An adjustable face milling cutter is carried on a turntable rotatable about a central axis that is coaxial with the cylindrical shell of the steam generator in which the tubesheet is located, to machine a circular path on the upper tubesheet surface. For complete circle-by-circle scanning of the tubesheet surface, the radius of the circular machined path is variable by virtue of mounting the milling cutter on the outer periphery of a circular mounting member turnable to different locked rotary positions about an off-center pivot axis on the turntable. The rotary support for the turntable is at its outer periphery, as provided by an encircling support ring which in turn is supported by a ball bearing assembly having an inner race secured to the turntable top and an outer race secured to the support ring top; teeth on the inner race being provided to accommodate a motor-operated drive gear. The support ring is centered in the steam generator shell by jack screws and is supported by such shell via a circular array of support lugs welded to the inner wall of such shell.
Inventors
- 👤 Frank M. Pekar
- 👤 Frank W. Cooper, Jr.
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-12-06 | 1986-06-07 | 1986-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-12-06 | 1990-06-07 | 1990-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-12-06 | 1994-06-07 | 1994-12-07 | $7700.00 | Window Closed / Lapsed |