Equalizing means for well tools
US4452311A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 1982 |
| Grant date | Jun 5, 1984 |
| Priority date | — |
| Expiry date | Sep 24, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/86936
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Pressure equalizing means for well tools having a tubular housing and an operator tube movable longitudinally therewithin, there being provided a valved bypass passage in the housing and a shoulder on the operator tube for engaging and opening the valve of the valved bypass passage upon longitudinal movement of the operator tube in the housing, the equalizing mechanism further including a pair of seal rings sealing between the housing and the operator tube above and below the valved bypass passage in the housing and a lateral passage in the wall of the operator tube normally above the pair of seals but movable under no-flow conditions with the operator tube to a position between the pair of seals prior to the operator tube shoulder contacting the valve of the bypass passage, thus avoiding damage to or flow cutting of the seals which normally form a secondary seal to provide bubble-tight integrity even if the valve in the bypass passage does not seal bubble tight.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.