CASING END TOOL

1 . A casing bit, comprising:

a mandrel; and

a bit body bonded to the mandrel, the bit body having an inner surface and an outer surface opposite the inner surface, the bit body consisting essentially of a matrix material of crystalline tungsten and a binder material.

2 . The casing bit of claim 1 wherein the bit body includes at least one blade.

3 . The casing bit of claim 2 wherein the blade includes at least one channel having a channel depth less than a thickness of the blade.

4 . The casing bit of claim 3 wherein the at least one channel is a blade channel radially following the blade.

5 . The casing bit of claim 3 wherein the blade includes a plurality of cutters, each cutter being bonded the blade.

6 . The casing bit of claim 5 wherein each cutter is a polycrystalline diamond cutter.

7 . The casing bit of claim 5 wherein each cutter comprises a diamond table mounted to a substrate of a first material.

8 . The casing bit of claim 5 wherein the blade further includes a plurality of cutter channels, each cutter channel running circumferentially and having a depth less than the blade thickness.

9 . The casing bit of claim 8 wherein the blade further comprises a plurality of cutter backup structures, and wherein one of the cutter channels is formed between adjacent ones of the cutter backup structures.

10 . The casing bit of claim 8 further including a cap mounted to the substrate of the first material, wherein the cap at least partially overlies, but is not attached to, the diamond table.

11 . The casing bit of claim 10 wherein the cap is made of or tipped with tungsten carbide.

12 . The casing bit of claim 1 further including a plurality of blind openings formed in either the inner surface or the outer surface.

13 . The casing bit of claim 1 wherein the binder material comprises brass.

14 . The casing bit of claim 13 wherein the binder material comprises a nickel-brass alloy.

15 . The casing bit of claim 1 wherein the inner surface includes a plurality of non-axisymmetric regions defined by raised portions of the inner surface.

16 . The casing bit of claim 15 wherein the raised portions comprise a raised boss structure or a raised land structure.

17 . The casing bit of claim 16 wherein the inner surface is configured such that during a drill out operation, drill out forces on the inner surface are first received by the raised boss structure or the raised land structure.

18 . A casing end tool, comprising:

a tool body bonded to a mandrel, the tool body including a face portion having an inner surface, the face portion comprising a crystalline tungsten matrix material.

19 . The tool of claim 18 wherein the tool body includes a plurality of blades.

20 . The tool of claim 18 wherein the inner surface includes a plurality of non-axisymmetric regions defined by raised portions of the inner surface.

21 . The tool of claim 20 wherein the raised portions comprise a raised boss structure or a raised land structure.

22 . The tool of claim 21 wherein the inner surface is configured such that during a drill out operation, drill out forces on the inner surface are first received by the raised boss structure or the raised land structure.

23 . The tool of claim 18 further including a plurality of blades, each blade supporting a plurality of cutter elements and further including at least one cutter channel having a depth less than a thickness of the blade.

24 . The tool of claim 23 wherein one of the blades further comprises a plurality of cutter backup structures, and wherein the cutter channel is formed between adjacent ones of the cutter backup structures.

25 . The tool of claim 18 wherein the tool is one of a casing bit or a casing reamer.

26 . A casing end tool, comprising:

a body bonded to a mandrel, the body having a plurality of blades, each blade having at least one channel having a channel depth less than a thickness of the blade.

27 . The tool of claim 26 wherein each blade supports a plurality of cutter elements, and the at least one channel running circumferentially along the blade.

28 . The tool of claim 26 wherein the body includes an inner surface and an outer surface opposite the inner surface, the inner surface having a non-axisymmetric region being defined by a raised region of the inner surface.

29 . The tool of claim 26 wherein the raised region comprises a raised boss or raised land structure.

30 . The tool of claim 26 wherein the body further comprises:

a wall defining an inner surface and an outer surface opposite the inner surface; and

a plurality of ports formed through the inner surface and the outer surface, each port having a surrounding thicker region of the wall interior to the bit body.

31 . The tool of claim 30 further including a port sleeve for each port, the port sleeve extending above the surrounding thicker region.

32 . The tool of claim 26 wherein the at least one channel is a blade channel radially following the blade.

33 . The tool of claim 26 wherein the body includes a face portion formed of a crystalline tungsten matrix material.