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:
Sep. 28, 2004
Filed:
Feb. 27, 2003
George Briley, San Antonio, TX (US);
Joe Sopko, Cedar Grove, WI (US);
Layne Christensen Company, Mission Woods, KS (US);
Abstract
A ground freezing method and system which circulates refrigerated heat transfer fluid through freeze pipes in the ground at a low temperature of at least −52° C. (−62° F.) to minimize drilling for the freeze pipe installation. The heat transfer fluid is preferably aqua ammonia (ammonium hydroxide) because of its beneficial characteristics in this application. The circulating heat transfer fluid is preferably cooled by a refrigeration system that includes low and high stage cycles arranged in a cascade relationship and using ammonia or another refrigerant in the high stage refrigeration system and carbon dioxide as the refrigerant in the low stage refrigeration system.