Retractible segmented packing ring for fluid turbines having gravity springs to neutralize packing segment weight forces
US5395124A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 4, 1993 |
| Grant date | Mar 7, 1995 |
| Priority date | — |
| Expiry date | Jan 4, 2013 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16J15/441
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A segmented seal ring and spring system for steam turbines for minimizing leakage between rotating and stationary components, and preventing damage and wear thereto, including a segmented seal ring, with first springs biased against the seal segments to urge the segments radially outward toward a large clearance position of the seal ring with respect to the turbine shaft. The springs urge the seal segments into the large clearance position at low shaft speeds and small turbine loads, whereas at medium to high flows and high working pressure, working fluid will overcome the spring forces and urge the seal segments into a small clearance position. Special gravity springs are provided in the lower half seal ring segments with the lower end of such springs seated against the turbine casing while the upper spring end is biased against the seal segment to produce an upward force which neutralizes the downward force caused by the weight of the segment. The gravity spring provides a spring force in the vertical direction which is equal to the weight of the segment which it supports so that the fluid pressure forces required to close the lower seal segments is the same as the radially outwa…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.