Self aligning stuffing box for pumpjack units
US5538080A · kind A · utility
Inventor
Key dates
| Filing date | Sep 2, 1994 |
| Grant date | Jul 23, 1996 |
| Priority date | — |
| Expiry date | Sep 2, 2014 |
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 a borehole. The stuffing box has a main body that terminates in a tubing adaptor at the lower end thereof by which it can be mounted to the upper end of a wellhead. The main body forms an upward opening chamber within which an annular seal assembly for sealingly engaging the polished rod is received. The polished rod reciprocatingly extends through the seal assembly and main body. The seal assembly and chamber together form a lubrication chamber that extends outwardly about the seal assembly. The seal assembly moves within the chamber radially of the passageway to align the polished rod with the production tubing of the wellhead. 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.