DRILLING BIT FOR CORE SAMPLING DEVICE FOR ISOLATED CORE SAMPLING Russian patent published in 2017 - IPC E21B10/48 E21B25/08 

FIELD: mining.

SUBSTANCE: drilling bit for the core sampling device for isolated core sampling contains a hollow body with external and end blades in which the well and core forming cutters are fixed, a thread made in the upper part of the body for connecting to the core sampling device body, washing holes made in the body of the drilling bit, leading from the cavity of the body into its end grooves located between the end blades, a central core lifting hole formed in the lower part of the drilling bit, a cylindrical bore made concentrically above the core lifting hole, a shell connected to core separation unit in the annular grooves in which there are split sealing rings made of flexible deformed metal. The drilling bit additionally contains a metal bushing rigidly fixed in a cylindrical bore and cooperating with the shell installed therein. The hardness of bushing material corresponds to the hardness of split sealing rings material. The core forming cutters fixed at the end blades with the rotation of the drilling bit circumscribe D1 diameter which is larger than Dk diameter of the drilled core by 510… mm. The final core forming cutters are additionally fixed in the core lifting hole above the end grooves and when the drilling bit is rotating they circumscribe a circle with diameter equal to the drilled core Dk diameter.

EFFECT: improved quality of the core sampled and operational durability of the drilling bit.

2 dwg, 2 app