Patent · US Expired

Reduced-shock landing collar

US6079496A · kind A · utility

107Cited by
13References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 4, 1997
Grant dateJun 27, 2000
Priority date
Expiry dateDec 4, 2017

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B21/10
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A landing collar is disclosed which defines a sealed cavity around its periphery. The landing collar has a seat to accept a sphere. Upon application of pressure on the sphere, the pressure rises on fluid in the chamber which surrounds the landing collar. At a predetermined pressure in the chamber, a rupture disc breaks which allows the fluid in the chamber to escape through a restrictor, thus regulating the rate of movement of the landing collar to expose gradually a bypass opening around the landing collar. Because the movement of the landing collar is regulated by the orifice adjacent the rupture disc, shock to the formation below is eliminated. In the event of sticking of the landing collar, an emergency release is possible since the landing collar is configured in two parts which can be pinned together. Upon an application of pressure higher than the pressure to break the rupture disc, the shear pins fail and a portion of the landing collar with the sphere disconnects to allow communication to the formation below.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.