Abstract: Downhole tool assembly (10) for mounting to a core barrel assembly (12) including a core tube (14) and a pair of split tubes (16). The downhole tool assembly (10) includes a downhole tool (18) and at least one sleeve (20) dimensioned to slidingly engage the split tubes (16) to inhibit radial movement of the split tubes (16) and receive and retain the downhole tool (18) coaxially with the core tube (14). Core ejection pistons (72), and methods for extracting a core from bedrock are also disclosed. A housing assembly (120) for a downhole tool, downhole assemblies (180, 200), and methods of assembling such assemblies are also disclosed.

Abstract: A shock absorber (24) for a downhole tool (18) is disclosed. The shock absorber (24) includes a downhole portion (32) defining a bore (34), and an uphole portion (36) configured for direct or indirect connection to the downhole tool (18). The uphole portion (36) has a stanchion (38) extending from one end and which carries a piston (40). The piston (40) is slidably engaged with the bore (34) to allow relative axial movement of the uphole portion (36) and the downhole portion (32). A first resiliently deformable member (42) is arranged between the uphole portion (36) and the downhole portion (32), and arranged to be compressed when the uphole portion (36) and downhole portion (32) move axially relative to each other in a first direction. A second resiliently deformable member (44) is arranged between an end of the bore (34) and the piston (40) to be compressed when the uphole portion (36) and downhole portion (32) move axially relative to each other in a second direction opposite to the first direction.

Abstract: A batch sample preparation apparatus (10) for preparing a geological sample for analysis is described and claimed. The apparatus (10) comprises a dryer (12) having a drying (chamber 52), a sample inlet (20) and at least one sample outlet (22), (24) communicating with the drying chamber (52), to a comminution device (14) in selective fluid communication via valves (26), (28) with the dryer (12) to selectively receive dried sample. The apparatus (10) has a source of fluid (74) introduced at the dryer (12) so that sample material may be transported from the dryer (12) to the comminution device (14) by fluid flow, which fluid flow also extracts the sample material from the comminution device (14) for collection and subsequent analysis.

Abstract: A drive sub for a drilling assembly includes a tubular body configured to receive and releasably engage a drilling tool. The body has inner and outer faces and further has a castellated edge provided on its operative downhole end, which edge defines a plurality of lugs separated from each other by intervening slots. In one aspect the drive sub has a contour profile provided at least partially along a circumference of the castellated edge, wherein the contour profile traverses the castellated edge substantially from the inner face to the outer face. In another aspect the drive sub has a channel provided in each of the lugs, wherein the channel at least partially traverses the lugs and leads from an inlet opening on the castellated edge to an outlet opening on the outer face. The contour profile and/or channel facilitate flow of drilling fluid and cuttings past the lugs during use.

Abstract: There is disclosed a torque transfer apparatus for a mineral drilling tool used in a downhole assembly of a drill string. The drilling tool has a downhole drill bit and one or more uphole drill bits spaced apart from the downhole drill bit, with the torque transfer apparatus being located between them. The apparatus has an axial bore therethrough for fluid flow and comprises first and second members being rotatably joined to each other. The apparatus rotationally couples and transfers torque between the first and second members when a torque difference between torque on the downhole drill bit and torque on the uphole drill bit is below a threshold torque value. The apparatus disengages the rotational coupling while the torque difference exceeds the threshold torque value. The flow rate of drilling fluid flowing through the axial bore is altered when the apparatus engages and disengages the coupling.

Abstract: A drive sub for a drilling assembly includes a tubular body configured to receive and releasably engage a drilling tool. The body has inner and outer faces and further has a castellated edge provided on its operative downhole end, which edge defines a plurality of lugs separated from each other by intervening slots. In one aspect the drive sub has a contour profile provided at least in partially along a circumference of the castellated edge, wherein the contour profile traverses the castellated edge substantially from the inner face to the outer face. In another aspect the drive sub has a channel provided in each of the lugs, wherein the channel at least partially traverses the lugs and leads from an inlet opening on the castellated edge to an outlet opening on the outer face. The contour profile and/or channel facilitate flow of drilling fluid and cuttings past the lugs during use.

Abstract: There is disclosed a torque transfer apparatus for a mineral drilling tool used in a downhole assembly of a drill string. The drilling tool has a downhole drill bit and one or more uphole drill bits spaced apart from the downhole drill bit, with the torque transfer apparatus being located between them. The apparatus has an axial bore therethrough for fluid flow and comprises first and second members being rotatably joined to each other. The apparatus rotationally couples and transfers torque between the first and second members when a torque difference between torque on the downhole drill bit and torque on the uphole drill bit is below a threshold torque value. The apparatus disengages the rotational coupling while the torque difference exceeds the threshold torque value. The flow rate of drilling fluid flowing through the axial bore is altered when the apparatus engages and disengages the coupling.

Abstract: A batch sample preparation apparatus (10) for preparing a geological sample for analysis is described and claimed. The apparatus (10) comprises a dryer (12) having a drying (chamber 52), a sample inlet (20) and at least one sample outlet (22), (24) communicating with the drying chamber (52), to a comminution device (14) in selective fluid communication via valves (26), (28) with the dryer (12) to selectively receive dried sample. The apparatus (10) has a source of fluid (74) introduced at the dryer (12) so that sample material may be transported from the dryer (12) to the comminution device (14) by fluid flow, which fluid flow also extracts the sample material from the comminution device (14) for collection and subsequent analysis.