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:
Dec. 20, 1994
Filed:
Apr. 16, 1993
John P Heller, Socorro, NM (US);
James V McLemore, Socorro, NM (US);
Zhongming Chen, Bryan, TX (US);
New Mexico Tech Research Foundation, Socorro, NM (US);
Abstract
The disclosure relates to an apparatus and method for determining the permeability and the porosity of small sections at and just below the surface of a slabbed sample of porous rock or other material. The measurement is performed by forcing air or other gas through a central passageway of a deformable (e.g. rubber) probe tip pressed against the surface of the sample to be tested. Permeability of the matter directly under the probe tip is computed from the ratio of flow rate into the sample to the pressure drop between the gas in the probe-tip and the ambient atmosphere. A preferred and an alternative means for measuring flow rate are disclosed involving the use of an optical interferometer to detect displacement of a bellows chamber. The apparatus of the invention includes a fact-acting valve such that immediately after calculation of the permeability of the sample under defined conditions, a precise value of the porosity of the same sample may be computed from the transient pressure change that is observed after cutting off air flow into the sample from the probe.