Patent GB191117268A successfully refreshed from Google Patents.
GB2212091A
Expired / Lapsed
GB
⏱️ 0.0 years remaining
Drilling equipment
Assignee: Boart Longyear Ltd
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Filing: 1987-11-12
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Granted: —
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Expires: 2007-11-12
Abstract
Abstract A percussion drill bit 10 has a cutting face 22 with cutting elements which may be in the form of buttons 20 (e.g. carbide material) or blades. The bit has a cylindrical body with helical flutes 32, which extend into a reduced diameter neck 30 disposed between face 22 and the cylindrical body. The bit 10 includes holes 28 extending therethrough to direct flushing medium (water) to the face 22 and a threaded socket for receiving threaded end of the drill rod. The bit 10 can be combined in a drill string with an extension body 12 and a rod connector 16, all of which have similar helical fluted surfaces. The body 12 has a threaded end received in the threaded socket of bit 10, and a threaded socket to receive therein a drill rod 14. The connector 16 has threaded sockets at its ends for receiving the rod 14 and a rod 18. The rods 14, 18, body 12 and bit 10 all have flushing passages therethrough. The angle of the helix defined by flutes 32 is between 20 DEG and 30 DEG . <IMAGE>
Inventors
- 👤 James Mcenery
- 👤 Joseph Dalton
- 👤 Gerard William Mcinerney
- 👤 Kjell Arne Andersson
- 👤 R David William Paul
Bibliographic Details
Application Number
—
Jurisdiction
GB
Data Source
google_patents
Last Synchronized
2026-10-23 05:22
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/10; E21B17/1092; E21B10/00; E21B10/36; E21B10/38; E21B10/44; E21B10/445; E21B17/22
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
86 words
A percussion drill bit having a cutting face carrying drilling inserts, a neck behind the cutting face, and a body portion extending back from the neck, the body portion having an outer cylindrical surface with helical flutes formed in the surface, a flushing hole extending through the bit to direct flushing medium to the cutting face, and a threaded socket for receiving the threaded end of the drill rod, the cylindrical outer surface extending up to that end of the bit remote from the cutting face.
Claim 2
Dependent Claim
86 words
A percussion drill bit having a cutting face carrying drilling inserts, a neck behind the cutting face, and a body portion extending back from the neck, the body portion having an outer cylindrical surface with helical flutes formed in the surface, a flushing hole extending through the bit to direct flushing medium to the cutting face, and a threaded socket for receiving the threaded end of the drill rod, the cylindrical outer surface extending up to that end of the bit remote from the cutting face.
Claim 3
Dependent Claim
13 words
A drill bit as claimed in Claim 1, which is a button bit.
Claim 4
Dependent Claim
13 words
A drill bit as claimed in Claim 1, which is a blade bit.
Claim 5
Dependent Claim
35 words
A drill bit as claimed in any preceding claim, wherein the diameter of the cylindrical surface is 4 to 8 millimetres less than the gauge diameter of the cutting face, when the bit is new.
Claim 6
Dependent Claim
89 words
In combination, a drill bit as claimed in any one of
Claims 1 to 4, together with an extension body, the extension body having a male threaded end, a female threaded socket coaxial with the male end, an outer cylindrical surface with helical flutes formed in the surface and a flushing hole extending through the body, the male threaded end being adapted to screw into the socket in the drill bit, and the thread of the female socket being adapted to receive the threaded end of a drill rod.
Claim 7
Dependent Claim
40 words
The combination as claimed in Claim 5, together with at least one drill rod connector, the drill rod connector being adapted to receive the threaded ends of two drill rods, and having a cylindrical outer surface with helical flutes therein.
Claim 8
Dependent Claim
94 words
A drilling string for drilling long straight holes in rock using a percussive drilling technique, the string comprising a drill bit, an extension body, at least two drill rods with threaded ends and at least one drill rod connector, the extension body being threadedly connected to the drill bit, one drill rod being threadedly connected to the extension body and the connector connecting the one drill rod to another drill rod, wherein all of the drill bit, the extension body and the connector have outer cylindrical surfaces with helical flutes formed in the surfaces.
Claim 9
Dependent Claim
94 words
A drilling string for drilling long straight holes in rock using a percussive drilling technique, the string comprising a drill bit, an extension body, at least two drill rods with threaded ends and at least one drill rod connector, the extension body being threadedly connected to the drill bit, one drill rod being threadedly connected to the extension body and the connector connecting the one drill rod to another drill rod, wherein all of the drill bit, the extension body and the connector have outer cylindrical surfaces with helical flutes formed in the surfaces.
Claim 10
Dependent Claim
38 words
A drill bit as claimed in any one of Claims 1 to 4, wherein the cylindrical surface has four flutes around the circumference, and the flutes and the lands which separate the flutes, have approximately equal circumferential extents.
Claim 11
Dependent Claim
28 words
A drill bit as claimed in any one of Claims 1 to 4 and 8, wherein the helix angle of the helical flutes is between 2C" and 30".
Claim 12
Dependent Claim
17 words
A drill bit as claimed in Claim 9, wherein the angle of the helix is approximately 26".
Claim 13
Dependent Claim
30 words
A drill bit as claimed in any one of Claims 1 to 4 or 8 to 10, wherein the helix is handed to conform to an anti-clockwise direction of rotation.
Claim 14
Dependent Claim
35 words
The combination as claimed in Claim 5 or Claim 6, wherein each cylindrical surface has four flutes around the circumference, and the flutes and the lands, which separate the flutes have approximately equal circumferential extents.
Claim 15
Dependent Claim
25 words
The combination as claimed in Claim 5, Claim 6 or Claim 12 wherein the helix angle of the helical flutes is between 20 and 30".
Claim 16
Dependent Claim
14 words
The combination as claimed in Claim 13, wherein the helix angle is approximately 260.
Claim 17
Dependent Claim
36 words
The combination as claimed in Claim 5 or Claim 6 or any one of Claims 12 to 14, wherein the helix formed by the helical flutes is handed to conform to an anti-clockwise direction of rotation.
Claim 18
Dependent Claim
34 words
A drilling string as claimed in Claim 7, wherein each cylindrical surface has four helical flutes around the circumference, and the flutes and the lands, which separate the flutes, have approximately equal circumferential extents.
Claim 19
Dependent Claim
24 words
A drilling string as claimed in Claim 7 or Claim 16, wherein the helix angle of the helical flutes is between 20C and 30".
Claim 20
Dependent Claim
15 words
A drilling string as claimed in Claim 17, wherein the helix angle is approximately 26".
Claim 21
Dependent Claim
38 words
A drilling string as claimed in any one of Claims 7 or 16 to 18, and arranged to be rotated anti-clockwise with the helix formed by the helical flutes being handed to conform to this direction of rotation.
Claim 22
Dependent Claim
20 words
A drilling string substantially as herein described with reference to and as shown in Figure 1 of the accompanying drawings.
Claim 23
Dependent Claim
20 words
A drilling string substantially as herein described with reference to and as shown in Figure 1 of the accompanying drawings.
Claim 24
Dependent Claim
26 words
A percussion drill bit substantially as herein described with reference to and as shown in any one of
Figures 1 to 5 of the accompanying drawings.
Claim 25
Dependent Claim
26 words
A percussion drill bit substantially as herein described with reference to and as shown in any one of
Figures 1 to 5 of the accompanying drawings.
Claim 26
Dependent Claim
24 words
The combination of a drill bit, an extension body and a drill rod connector, substantially as herein described with reference to the accompanying drawings.
Claim 27
Dependent Claim
24 words
The combination of a drill bit, an extension body and a drill rod connector, substantially as herein described with reference to the accompanying drawings.
References Cited (Backward Citations)
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