Impregnation Depths for Stepped and Semi-Round Profile

This bit crown profile is only offered with a standard impregnation depth of 6 mm (0.24 inch).

 

This bit crown profile is only intended for use on core bits with very thick kerf widths. It is available in customer specified impregnation depths ranging from 6 mm (0.24 inch) through 14 mm (0.55 inch) inclusive.

Impregnation Depths for Flat-Face Profile Core Bits

This bit crown profile is offered in standard impregnation depths of 6 mm (0.24 inch), 9 mm (0.35 inch) and 12 mm (0.47 inch). Note that impregnation depths greater than 9 mm (0.35 inch) are NOT available matrix core bits as well as those with kerf widths of less than 0.33 inch (8.4 mm). Customer specified impregnation depths of up to 14 mm (0.55 inch) are available on request for core bits with kerf widths of 0.39 inch (10 mm) or greater.

Impregnation Depths for V-Ring Profile Core Bits

This bit crown profile is offered in standard impregnation depths of 6 mm (0.24 inch), 9 mm (0.35 inch) and 12 mm (0.47 inch). Note that impregnation depths greater than 9 mm (0.35 inch) are NOT available matrix core bits as well as those with kerf widths of less than 0.33 inch (8.4 mm). Customer specified impregnation depths of up to 14 mm (0.55 inch) are available on request for core bits with kerf widths of 0.39 inch (10 mm) or greater.

Impegration Depth

The term "impregnation depth" refers to the thickness of the diamond impregnated matrix layer on a core bit crown as shown in the illustration to the right. The variable “y” is used to define the impregnation depth dimension for a particular core bit.

IDP offers many sizes of core bits with standard impregnation depths of 6 mm (0.24 inch), 9 mm (0.35 inch) and 12 mm (0.47 inch). Other customer defined impregnation depths are available on request. Unless otherwise specified, a standard 9 mm impregnation depth is supplied for most North American sizes of core bits while a standard 6 mm impregnation depth is supplied for all thin-walled metric “I”, “T”, “TT”, “T2” and “T6”-series core bits.

As the price of an impregnated core bit increases from a 6 mm impregnation depth through to a 12 mm impregnation depth, consideration should be given to the economics of selecting a particular impregnation depth. While the initial cost of a core bit with a 6 mm depth of impregnation is relatively low, the expected overall bit life will also be lower than that of a bit with a thicker impregnation depth. For this reason, a 6 mm impregnation depth is generally recommended for use in shallow drill holes or for non-Wireline applications where more frequent bit changes are not objectionable. Conversely, the higher initial cost of a core bit with a 12 mm impregnation depth is largely offset by its inherently long bit life when used to drill extremely deep holes. The cost saving benefit is realized through reduced down time on the drill rig that would otherwise be required for tripping the drill string for bit changes.

Impregnated diamond matrices with matrix layer

IDP manufactures a range of impregnated diamond matrices with matrix layer metal bonds that range from hard, abrasion-resistant types to soft, ductile types. In general, a hard, abrasion-resistant matrix would be used to drill a soft, abrasive, unconsolidated formation while a soft, ductile matrix would be used to drill an extremely hard, non-abrasive, consolidated formation. The idea is to match the bit matrix hardness to the formation hardness in order that the metal bond of the matrix layer will erode at a controlled rate during normal drilling operation. This controlled erosion of the matrix layer metal bond will in turn continually expose new layers of sharp synthetic diamonds until the matrix layer of the bit crown is totally consumed.