Subsurface release cementing plug apparatus and methods
US5762139A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 1996 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Nov 5, 2016 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B33/165
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The present invention provides an improved subsurface release cementing plug apparatus for use in a string of pipe during the cementing of the pipe in a well bore. The apparatus includes a hollow cementing plug seat member adapted to be connected in the string of pipe near the bottom thereof and a cementing plug assembly releasably connectable to a circulation tool or casing running tool in the top of the string of pipe. The cementing plug assembly includes a top cementing plug having an external annular seating surface formed thereon for sealingly engaging a top internal annular seating surface of the cementing plug seat member, and a bottom cementing plug releasably connected to the top cementing plug having an external annular seating surface formed thereon for engaging a bottom internal annular seating surface of the cementing plug seat member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.