The Overshot is dropped or pushed into the drill string to bring back the inner – tube assembly by means of wireline cable hoist.


The Locking Coupling attaches the drill string to the outer – tube assembly and maintain a mating surface which the head assembly bolt ride against while performing the drilling.

Besides this, locking couplings maintains directional control for the core barrel assembly by means of wear resistant preserving pads that wear down against the drill hole wall.


The adapter coupling matches between the locking coupling and core barrel outer–tube, maintaning the pocket into which the head assembly secures deploy.


The head assembly maintains latching and also evoting spearpoint mechanism to grant insertion and bringing back of the inner–tube assembly, a bearing assembly to let on the inner – tube to remain stationary and avert sample damage while driling, fluid pressure operating indications and fluid control valves. All head assemblies integrate a shut off valve assembly which maintains a fluid pressure signal to drill operator, revealing a full or blocked inner–tube.


The Landing Ring sits in the upper–end of the outer tube and is recollected  by the mating coupling. As the inner tube assembly trips into drill string, the landing shoulder on the Head Assembly collides the Landing Ring setting the inner tube assembly into drilling position.


The outer – tube houses  the inner–tube assembly and conncets to the diamond products piercing the hole. The increased wall thickness of the outer–tube maintains supplementary rigidity for directional control and a tighter hole annulus for increased fluid velocity and swift cuttings discharging for bit performance. Multiple outer–tubes can be amassed to extend the potential core sample lenght.


The inner- tube takes the core sample as performing the drilling progresses. Multiple inner–tubes can be amassed with couplers or extensions to get longer core samples.


Installed in the Reaming Shell or in mated outer – tube extensions, the replaceable and reversible inner–tube stabilizer maintains centralizing for advanced sample recovery and a bearing between the stationary inner–tube and the rotating outer–tube.


The core lifter is a pressed steel , split collar with a tapered body that matches to a tapered socket in the core lifter case.

In a core breaking operation, the drill string is climbed off bottom and the core sample starts to slide out of the inner–tube. Grip marks on the inner surface of the core lifter takes the moving core sample and pull the core lifter towards the smaller end of the tapered socket in the core lifter case. The core lifter is compressed againstthe core sample and retainsit after it has crushed, granting retrieval to surface.


The core lifter case mates to the inner-tube and houses the core lifter in a tapered socket which controls movement of the core lifter. As the drill string is lifted during a core breaking operation, the core lifter case bottoms out on the inside of the drill bit transferring the pullback load from the Drill string to the core lifter until the core sample breaks


The stop ring is a compressed steel snap ring devised to seat into a mating groove, and maintaining the core lifter in the core lifter case.


Wireline systems are optimal for use in most drilling conditions and applicable in standard DCDMA hole sizes.

Son–Mak presently offers two models of the wireline core barrel system:

O / O 3  

O wireline systems, includes the core barrel assembly and the overshot assembly. Both assemblies are essential to the wireline system.

The core barrel assembly is formed by the inner–tube assembly and outer -tube assembly.

The inner – tube assembly is formed:

  • Head assembly
  • Inner – tube
  • Core lifter case
  • Core lifter
  • Stop ring

The inner–tube assembly takes the core sample during the performing of the drilling process and seperate of the outer–tube assembly.

The outer – tube assembly is formed by the remainder of the core barrels components:

  • Locking Coupling
  • Adapter Coupling
  • Outer–tube

The outer tube assembly always stands at the bottom of the hole and houses the inner–tube assembly during the drilling process.

O 3

O3 Wireline systems contains the same assemblies as the O but utilize a third tube called an innter – tube liner or split tube.The liner is housed inside the inner- tube.

O3 systems implements integral core recovery when drilling coal, clay bearing or highly fractured formations. The liner, or split tube, contains the core sample in its received state for easier loading into sample trays or for storage and following presentations to the geologist. The O3 system is only applicable in surface configurations and is possible in N Wireline, H Wireline and P Wireline sizes.