Tubular lost borehole closure

US4362440A · kind A · utility

Assignee

• Bergwerksverband GmbH · DE

Inventors

• Otto-Ernst Glaesmann · Dortmund, DE
• Frank Meyer · Essen, DE
• Walter Marsch · Recklinghausen, DE

Key dates

• Filing date: Jan 25, 1980
• Grant date: Dec 7, 1982
• Expiry date: Jan 25, 2000

Classification

• Technology area (CPC E): Fixed Constructions
• CPC primary: E21B33/129
• WIPO field: Civil engineering
• WIPO sector: Other fields

Abstract

A borehole closure, especially for injection of plastic material or cement into a borehole formed into rock for solidifying the latter and comprising a tube, a one-way valve connected to the leading end of said tube, a holding element including a spreading cone cooperating with a spreadable shell surrounding the tube in the region of its leading end, which in turn is followed by an axially compressible and radially expandable sealing element in form of a rubber sleeve surrounding the tube. In order to place the lost borehole closure at any desired distance from the outer end of the borehole, a plurality of tube sections and connecting bushings are provided for connecting the tube sections with different restraining forces to each other and to the trailing end of the tube, with one of the tube sections extending beyond the outer end of the borehole. An anchor plate may be provided surrounding the tube section projecting beyond the outer end of the borehole and is held against the rock by a lockscrew so that the arrangement may be used as a spreading anchor. A screw nipple is fixed to the outer end of the one tube section for turning the latter and the other tube sections and the tub…