US 4,566,545 AGranted

Coring device with an improved core sleeve and anti-gripping collar with a collective core catcher

AssigneeNorton Christensen, Inc.

InventorsArthur L. Story, Michael Filshtinsky

Life of this patent

Estimating the term…

Loading patent…

Abstract

An improved coring device that incorporates a nonrotatable inner barrel disposed within the outer driving structure of the drill string which is coupled to the coring bit. A woven metal mesh sleeve is circumferentially mounted outside the inner barrel and tucked around its lower end. The lower end of the mesh sleeve in the inner barrel is in turn connected to a stripper tube which is pulled upwardly during the coring operation. As the core is cut by the coring bit and enters the inner barrel, the woven metal mesh sleeve is disposed about the core and constricts about the core when pulled upwardly by the stripper tube. The opposing end of the woven metal mesh sleeve is under a weight which serves to compress the metal sleeve when outside the inner barrel, thereby increasing its diameter. The plurality of wedge-shaped segments located on the top of the sleeve are collectively brought together to form a core catcher when that end of the woven metal mesh sleeve to which the segments are connected is drawn around and into the lower end of the inner barrel.

Claims18

Dependent claims

An improved coring apparatus used in combination with a coring bit and drill string comprising:

an outer driving structure adapted to be connected at one end to said coring bit for cutting a core in a bore hole, and at the other end to the lower end of said drill string in telescoping and co-rotatable manner therewith;
an inner barrel disposed within said outer driving structure and including a lower end portion adjacent to said bit;
first means supporting said inner barrel in spaced relationship to said outer driving structure while permitting rotation of said driving structure with respect to said inner barrel;
a woven metal mesh sleeve mounted in surrounding relation on at least a portion of the exterior surface of said inner barrel, said sleeve including a leading portion adapted to be positioned within the inner barrel and initially to receive a core as it is cut, said sleeve having a predetermined normal diameter which is greater than the diameter of the sleeve in tension;
second means, connected to a free end of said sleeve opposite said leading portion of said sleeve, for maintaining the portion of said sleeve which surrounds said inner barrel in compression and to maintain an inside diameter greater than the outside diameter of said inner barrel of said portion of said sleeve surrounding said inner barrel while the portion of said sleeve positioned inside said inner barrel being in tension to grip and compress a core received within said sleeve and having an outside diameter less than the inside diameter of said inner barrel when in tension, wherein said second means is also for engaging said core when said means is drawn into said inner barrel, and
third means positioned within said inner barrel and connected to the leading portion of said sleeve to draw said sleeve within said inner barrel and to apply tension to the portion of said sleeve within said barrel to encase and grip said core as it is cut.

3 more elements

The improved coring apparatus for use in combination with a coring bit and drill string to retrieve a core comprising:

an outer telescoping supporting structure adapted to be connected at one end to said coring bit and at the other end to said pipe string;
an inner barrel supported within said supporting structure and including a lower end portion adjacent to said bit;
intermediate tube means supported by said supporting structure and spaced radially outwardly of said inner barrel to form a chamber therebetween;
flexible sleeve means positioned in said chamber and including a free end and an opposing portion received in the interior of said inner barrel, said sleeve means being mounted and supported with respect to said inner barrel to encase a core received by said portion of said sleeve positioned within said inner barrel, said sleeve means being drawn into said inner barrel as said core is cut;
and
terminal means between said intermediate tube means and said barrel contacting the free end of said sleeve, said terminal means for providing a constricting force about said core when said terminal means is drawn into said inner barrel.

3 more elements

Dependencies are inferred from the claim text.