ROCK SAMPLE CHARACTERISTICS DETERMINATION DEVICE Russian patent published in 2006 - IPC E21C39/00 

FIELD: devices for testing in situ the hardness or other properties of minerals, particularly to determine specific electric resistivity and resiliency of rock under conditions stimulating in-situ conditions.

SUBSTANCE: device comprises chamber with core holder, as well as nipples provided with fluid inlet and outlet pipes, nipple with liquid supply pipe to create pre-stressing pressure, core specific electric resistivity determination unit connected with fluid inlet and outlet pipes, electronic measuring unit, which determines time of longitudinal and transversal wave spreading in rock core and two inserts made as stepped cylinders. Core holder is arranged in sealed chamber and made as sealed dielectric shell having the first end enclosing movable electrode and the second end enclosing fixed end bush. Space defined by the ends is communicated with fluid inlet and outlet pipes. Cavity defined by outer elastic shell surface and inner chamber walls is connected to liquid inlet nipple to create pre-stressing pressure. Insert ends of having lesser diameters are installed in cylindrical depressions formed in movable electrode and having the same diameter. The second stages have diameters equal to core diameter and provided with through orifices to supply fluid to core and to remove fluid from core. The second insert stage ends have fluid distribution grooves, wherein above through orifices cross one of the grooves. Lesser diameter insert end is provided with piezoelectric plates connected with the electronic measuring unit, which determines time of longitudinal and transversal wave spreading in rock core. Grooves formed in inner insert ends may be concentric and connected one to another with the same radial grooves. Groove cross-section defines triangular having 60°±1° vertex angle. Piezoelectric plates are formed of piezoceramics at an angle to crystallographic axis Z, wherein the angle provides serial emission and receiving of transversal and longitudinal waves. For particular piezoceramics this angle is equal to 70°±3°. The electronic measuring unit structure is also disclosed.

EFFECT: increased research reliability and reduced research time.

6 cl, 3 dwg