Self aligning stuffing box for pumpjack units
US5343944A · kind A · utility
Inventor
Key dates
| Filing date | Sep 10, 1992 |
| Grant date | Sep 6, 1994 |
| Priority date | — |
| Expiry date | Sep 10, 2012 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B33/08
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A self aligning stuffing box for a pumpjack unit of the type having a polished rod reciprocatingly extending therethrough and downhole to a pump located at the lower end of the borehole. The stuffing box is an annular main body having a tubing adaptor at the lower end by which it can be mounted to the upper end of a well bore. A spool receiving cavity is located within the main body concentrically respective to the polished rod, and an annular spool is received within the cavity. The polished rod reciprocatingly extends through the spool and main body. A seal assembly is mounted to the inner surface of the spool for sealingly engaging the polished rod. The spool cooperates with the cavity to form a lubrication chamber that extends outwardly and about the spool. The spool moves within the spool receiving cavity radially of the passageway to align the polished rod with the wellbore. The adaptor forms a pack-off that isolates the seal from the wellbore, and provision is made by which the seal assembly can be replaced without removing the polished rod from the pumpjack unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.