The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 26, 2002
Filed:
May. 19, 2000
Applicant:
Inventor:
Peter Ellenberger, Feldmeilen, CH;
Assignee:
MBT Holding AG, Zurich, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21D 9/06 ; E21D 9/12 ;
U.S. Cl.
CPC ...
E21D 9/06 ; E21D 9/12 ;
Abstract
A method of boring a tunnel through a stratum utilizing a shield tunneling apparatus, the process comprising the injection into the stratum at the cutting face of an aqueous material comprising (a) from 0.005-0.05% by weight of a polyethylene oxide of weight-average molecular weight from 2,000,000 to 8,000,000 (b) from 0.05-0.5% by weight of a sulphate-containing anionic surfactant. The method is effective even in difficult soils.