WO2006056010A1 - Induction-hardened drill string components - Google Patents

Induction-hardened drill string components Download PDF

Info

Publication number
WO2006056010A1
WO2006056010A1 PCT/AU2005/001777 AU2005001777W WO2006056010A1 WO 2006056010 A1 WO2006056010 A1 WO 2006056010A1 AU 2005001777 W AU2005001777 W AU 2005001777W WO 2006056010 A1 WO2006056010 A1 WO 2006056010A1
Authority
WO
WIPO (PCT)
Prior art keywords
drill
drill steel
hardened
steel
hardness
Prior art date
Application number
PCT/AU2005/001777
Other languages
French (fr)
Inventor
Todd Andrew Haines
Original Assignee
Todd Andrew Haines
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from AU2004906674A external-priority patent/AU2004906674A0/en
Application filed by Todd Andrew Haines filed Critical Todd Andrew Haines
Publication of WO2006056010A1 publication Critical patent/WO2006056010A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/06—Surface hardening
    • C21D1/09—Surface hardening by direct application of electrical or wave energy; by particle radiation
    • C21D1/10—Surface hardening by direct application of electrical or wave energy; by particle radiation by electric induction
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/06—Surface hardening
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/34—Methods of heating
    • C21D1/42—Induction heating
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
    • E21B17/10—Wear protectors; Centralising devices, e.g. stabilisers
    • E21B17/1085—Wear protectors; Blast joints; Hard facing
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2221/00—Treating localised areas of an article
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2221/00—Treating localised areas of an article
    • C21D2221/10—Differential treatment of inner with respect to outer regions, e.g. core and periphery, respectively
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/25—Process efficiency

Definitions

  • THIS INVENTION relates to induction-hardened drill string components; and to drill strings incorporating such components.
  • the invention is particularly suitable for, but not limited to, drill string components, and drill strings, for single-pass blast hole drilling.
  • a single-pass drill string will normally consist of a top sub, two drill steels and a bit sub.
  • the top sub screws into the rotary head that provides pull-down and rotary drive for the drilling operation.
  • the first drill steel screws into the top sub and the second drill steel screws into the first steel.
  • the bit sub screws into the second drill steel.
  • a large amount of air is passed through the inside of the drill string to force the cuttings, generated from the rotary drill bit or down-hole hammer, past the outside of the drill string.
  • the drill string is 25 mm-75mm smaller in diameter than the bit.
  • the cuttings blown through the annular cavity around the drill string may be travelling at 2000-15,000 feet per
  • diameter of the drill string are the main factors affecting wear rates on the drill string from this type of wear.
  • Sub drill is required due to the fact that when a pattern is drilled, and then blasted, it does not leave a completely flat surface. If the required
  • the sub-drill is particularly hard on the drill string as it consists of broken rock that rubs against the drill string, while the bit works its way down
  • a single-pass drill string does not wear out threads, as the string is
  • the method of extending the life of the drill string is by applying "hardfacing" using a welding process. This process normally
  • AISI 4140 for the tool joints and A106GB (mild steel pipe) or AISI 4140 for the connecting pipe.
  • the wear properties of the AISI 4140 connecting pipe are normally not that different than the A106GB. However, I have observed on one mine site 30% to 40% less wear on the 4140 tool joint adjacent to A106GB connecting pipe.
  • the AISI 4140 drill steels normally cost around 30% more to manufacture due to the more expensive pipe and therefore it is not economic or at best marginally economic to utilise 4140 connecting pipe.
  • the 4140 tool joints have a hardness of approximately 280-320 Brinell, where the A106GB connecting pipe is around 1650 Brinell.
  • the difference in wear observed on the site appears to be directly related to the hardness of the material. A major component of the wear in single-pass drilling is caused by the drill string rubbing on the side of the hole and this mainly happens in sub drill or ground that has been blasted already.
  • the 4140 material tends to not be gouged as deeply by the sharp rock compared to the A106GB connecting pie and therefore wears less.
  • the 4140 material used for the tool joints has the same chemical make-up as the available 4140 connecting pipe, but the 4140 tool joint material is supplied quenched and tempered.
  • the 4140 connecting pipe is not quenched and tempered, it is supplied as hot rolled and the hardness is around the 190-230 Brinell.
  • Single-pass drilling is normally used in metalliferous mining, Multi ⁇ pass drilling is used more in coal mines, where the seams are up to 120m below the surface, and at times, up to 7 drill steel sare coupled together to drill down to 85m.
  • coal mines are not as abrasive as metalliferous mines, and the drill steel s do not wear as quickly.
  • the wear also, tends to be caused more by the sandblasting effect of the cuttings passing the outside diameter of the steel at up to 12000 feet/minute.
  • the 4140 tool joints and A106GB connecting pipe tend to wear at the same rate.
  • the pipe is 3-4mm smaller on the bottom of the pipe and this is normally a linear wear from bottom to top as the bottom of the pipe is in the ground subject to sandblasting longer than the top.
  • the present invention resides in a method of induction
  • hardening a drill steel including the steps of: supporting the drill steel to be hardened in a support member; placing a hollow induction heating head and a hollow quenching head about the drill steel; advancing the induction heating head along the drill steel to heat an outer layer on the drill steel; and advancing the quenching head along the drill steel, to quench the outer layer of the drill steel to above the desired hardness and depth of hardness.
  • the induction heating head and the quenching head are provided in a combined unit.
  • the drill steel is manufactured from AISI 4140 material, and the outer "layer" of the material is hardened to a depth of at least 6mm, and to a hardness of at least 600 Brinell.
  • the support member may be a lathe or other suitable support structure.
  • the temperature of the drill steel is closely monitored by optical pyrometers during the heating step.
  • the present invention resides in a drill steel, or other drill string component, hardened by the method, of the first aspect, hereinbefore described.
  • the present invention resides in a drill string incorporating one or more drill steels or drill string components, hardened by the method of the first aspect.
  • FIG. 1 is a side view indicating the general appearance of a single- pass mining drilling string
  • FIG. 2 is a sectional side view of a typical drill string hardened in accordance with the present invention
  • FIG. 3 is a schematic side elevation view of a drill string being hardened in accordance with the invention.
  • FIG. 4 is an end sectional view of the induction heating head/ quenching head unit taken in line 4-4 on FIG. 3.
  • FIG. 1 illustrates an example of a typical single-pass drill string 10, where a cushion sub 11 and saver sub 12 operably connect at least one drill steel 13 to a rotary drilling head 14.
  • a bit sub 15 connects the, or lowermost, drill steel 13 to the rotary drill bit or down-hole-hammer (not shown).
  • the drill string 10 is stabilised by a deck bush 16 on the drill rig (not shown).
  • FIG. 2 illustrates a cross-sectional side view of a drill string 13, manufactured of 4140 material, where an induction-hardened outer layer 13a, preferably 6.0mm-10.00mm thick, and of at least 600 Brinell hardness, is formed along the string.
  • NB (i) The screw threadsi 3b (of the pin tool joint 13c) are not hardened.
  • the outer layer of the recesses 13d, engageable by uncoupling tools, are preferably hardened (eg to a 6.0mm thickness) to a hardness greater than 4140 pipe, but less than the at least 600 Brinell hardness of the 5 layer 13a.
  • the hardness of the outer layer of the recesses 13d may be in the range of 280-500 Brinell.
  • the drill steel 13, of 4140 material for the tool joints and the connecting pipe is supported in a long (eg. 12m bed) lathe 20 by gripping one end with a chuck 21 and supporting the other by a chuck or a tailstock 22.
  • the induction heating and quenching unit 30 is hollow and passes s about the drill steel 13.
  • the induction heating and quenching unit 30 is mounted on the lathe carriage 23 and its rate of advance along the lathe 20 is controlled by a feed screw 24.
  • An induction heating head 31 is connected to a high frequency o electrical power source 32 via suitable power cables 33, and closely surrounds the pipe 13.
  • the quenching head 34 is located adjacent to, and downstream of, the induction heating head 31 , and is connected to a source of quenching liquid (not shown) by suitable pipes 35.
  • the drill steel 13 is heated by electrical induction generated by the induction heating head 31.
  • a current is oscillated at high frequencies through the pipe wall or tool joint.
  • the resistance of the material to the electron flow converts the electrical energy into heat, which is closely regulated and monitored by optical pyrometers 36 mounted on the unit 30.
  • the relative speed of the drill steel 13 passing through the induction heating head 31 , and the power applied, is precisely controlled to achieve heat balance at the required temperature.
  • the drill steel 13 is then subjected to quenching in the quenching head 34 to achieve the desired hardness and depth of hardness.
  • the induction head 34 has quenching sprays 37, integral to the head 34, directing quenching liquid onto the drill steel 13.
  • a potential problem in the process could be the drill steel 13 bending as it is heated and quenched. To limit this bending, the drill steel 13 can be rotated as the induction heating and quenching unit 30 is passed over it - this will tend to evenly distribute the heating and quenching around the drill steel 13. If the drill steel 13 does bend, it is proposed to either hydraulically straighten the drill steel or spot heat the drill steel to straighten it.
  • the induction hardening method need not be limited to drill steels, as other drill string components, such as bit subs and stabilisers may be hardened as well.
  • the softer outer layers of the recess 13d will still be harder than standard quenched and tempered 4140 material, but not too hard that the dies will not grip. (The "softer" outer layers of the recess 13d are preferably hardened, eg., in the range of 280-500 Brinell.)

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Materials Engineering (AREA)
  • Thermal Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Geochemistry & Mineralogy (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Fluid Mechanics (AREA)
  • Earth Drilling (AREA)

Abstract

A drill string steel (13) has an outer layer (13a), at least 6mm deep, hardened to a hardness of at least 600 Brinell, using an induction heating head (31) and a quenching head (34), moved along the drill steel (13) as it rotates in a supporting lathe (20). Portions or recesses (13d) of the drill steel (13), to be engaged by tools, have an outer layer hardened to a hardness in the range of 280-500 Brinell.

Description

TITLE
INDUCTION-HARDENED DRILL STRING COMPONENTS BACKGROUND OF THE INVENTION
1. Field of the Invention THIS INVENTION relates to induction-hardened drill string components; and to drill strings incorporating such components.
The invention is particularly suitable for, but not limited to, drill string components, and drill strings, for single-pass blast hole drilling.
2. Prior Art A large proportion of production blast hole drilling worldwide is single pass. Single-pass refers to the technique of drilling a hole down, usually 15m - 19m deep, without having to add another drill steel to the string to get to the required depth.
Single-pass drill rigs generally have longer masts than multi-pass drill rigs to fit the drill string into. A single-pass drill string will normally consist of a top sub, two drill steels and a bit sub. The top sub screws into the rotary head that provides pull-down and rotary drive for the drilling operation. The first drill steel screws into the top sub and the second drill steel screws into the first steel. The bit sub screws into the second drill steel. The rotary drill bit, or down-the-hole hammer screws into the bit sub.
A large amount of air is passed through the inside of the drill string to force the cuttings, generated from the rotary drill bit or down-hole hammer, past the outside of the drill string. Normally the drill string is 25 mm-75mm smaller in diameter than the bit. The cuttings blown through the annular cavity around the drill string may be travelling at 2000-15,000 feet per
minute. The abrasiveness, velocity and size of the cuttings passing the outer
diameter of the drill string are the main factors affecting wear rates on the drill string from this type of wear.
There is also another factor affecting wear rates of the first 2.5m-3.5m of the drill string connected to the drill bit. This factor is the requirement of drilling through 2.5m-3.5m of sub drill. Sub drill is set by how far you drill past the level of a new bench that will be worked to when the ground is
blasted. Sub drill is required due to the fact that when a pattern is drilled, and then blasted, it does not leave a completely flat surface. If the required
bench height is 18m, then the holes may be 20.5m-21.5m deep. This leaves
a 2-4m of shot ground that can be bulldozed or graded flat after the shovel has come through taking out the 18m of ore or waste.
The sub-drill is particularly hard on the drill string as it consists of broken rock that rubs against the drill string, while the bit works its way down
to unblasted material. Air is lost into the sub drill laterally due to the porous nature of the material, and does not create a sufficiently strong uphole blast
of air to clear the broken rock, until the bit is engaged in the unblasted
material. A single-pass drill string does not wear out threads, as the string is
coupled together until one of the components wears out or breaks.
At present, the method of extending the life of the drill string is by applying "hardfacing" using a welding process. This process normally
consists of a device to rotate the drill string while it is in the horizontal plane, and a wire feeder that welds a run of hardfacing onto the component. The widths of these welds vary from approximately 6mm-40mm, and the entire length of the drill string can be hardfaced in this manner and has been done in the past. However, this process is expensive and time consuming. At present, most drill steels are manufactured using AISI 4140 for the tool joints and A106GB (mild steel pipe) or AISI 4140 for the connecting pipe.
The wear properties of the AISI 4140 connecting pipe are normally not that different than the A106GB. However, I have observed on one mine site 30% to 40% less wear on the 4140 tool joint adjacent to A106GB connecting pipe. The AISI 4140 drill steels normally cost around 30% more to manufacture due to the more expensive pipe and therefore it is not economic or at best marginally economic to utilise 4140 connecting pipe. The 4140 tool joints have a hardness of approximately 280-320 Brinell, where the A106GB connecting pipe is around 1650 Brinell. The difference in wear observed on the site appears to be directly related to the hardness of the material. A major component of the wear in single-pass drilling is caused by the drill string rubbing on the side of the hole and this mainly happens in sub drill or ground that has been blasted already. The 4140 material tends to not be gouged as deeply by the sharp rock compared to the A106GB connecting pie and therefore wears less. The 4140 material used for the tool joints has the same chemical make-up as the available 4140 connecting pipe, but the 4140 tool joint material is supplied quenched and tempered. The 4140 connecting pipe is not quenched and tempered, it is supplied as hot rolled and the hardness is around the 190-230 Brinell. Single-pass drilling is normally used in metalliferous mining, Multi¬ pass drilling is used more in coal mines, where the seams are up to 120m below the surface, and at times, up to 7 drill steel sare coupled together to drill down to 85m. Normally, coal mines are not as abrasive as metalliferous mines, and the drill steel s do not wear as quickly. The wear, also, tends to be caused more by the sandblasting effect of the cuttings passing the outside diameter of the steel at up to 12000 feet/minute. The 4140 tool joints and A106GB connecting pipe tend to wear at the same rate. There is a tendency for the pipe to be 3-4mm smaller on the bottom of the pipe and this is normally a linear wear from bottom to top as the bottom of the pipe is in the ground subject to sandblasting longer than the top.
SUMMARY OF THE PRESENT INVENTION It is an object of the present invention to induction harden complete drill steels. It is a preferred object to harden such steels to a depth of at least
6mm and preferably to a hardness of >600 Brinell.
It is a further preferred object to effect the hardening using induction hardening and quenching heads which are hollow and passed along the drill steels. Other preferred objects will become apparent from the following
description.
In one aspect, the present invention resides in a method of induction
hardening a drill steel, including the steps of: supporting the drill steel to be hardened in a support member; placing a hollow induction heating head and a hollow quenching head about the drill steel; advancing the induction heating head along the drill steel to heat an outer layer on the drill steel; and advancing the quenching head along the drill steel, to quench the outer layer of the drill steel to above the desired hardness and depth of hardness.
Preferably, the induction heating head and the quenching head are provided in a combined unit. Preferably, the drill steel is manufactured from AISI 4140 material, and the outer "layer" of the material is hardened to a depth of at least 6mm, and to a hardness of at least 600 Brinell.
The support member may be a lathe or other suitable support structure. Preferably, the temperature of the drill steel is closely monitored by optical pyrometers during the heating step.
Preferably, where region(s) of the drill steel are to be engaged by tools, eg., for uncoupling, an outer layer of the material in the region(s) hardened to a lower Brinell hardness. In a second aspect, the present invention resides in a drill steel, or other drill string component, hardened by the method, of the first aspect, hereinbefore described.
In a third aspect, the present invention resides in a drill string incorporating one or more drill steels or drill string components, hardened by the method of the first aspect.
BRIEF DESCRIPTION OF THE DRAWINGS To enable the invention to be fully understood, preferred embodiments will now be described with reference to the accompanying drawings in which:
FIG. 1 is a side view indicating the general appearance of a single- pass mining drilling string;
FIG. 2 is a sectional side view of a typical drill string hardened in accordance with the present invention; FIG. 3 is a schematic side elevation view of a drill string being hardened in accordance with the invention; and
FIG. 4 is an end sectional view of the induction heating head/ quenching head unit taken in line 4-4 on FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates an example of a typical single-pass drill string 10, where a cushion sub 11 and saver sub 12 operably connect at least one drill steel 13 to a rotary drilling head 14. A bit sub 15 connects the, or lowermost, drill steel 13 to the rotary drill bit or down-hole-hammer (not shown).
The drill string 10 is stabilised by a deck bush 16 on the drill rig (not shown).
FIG. 2 illustrates a cross-sectional side view of a drill string 13, manufactured of 4140 material, where an induction-hardened outer layer 13a, preferably 6.0mm-10.00mm thick, and of at least 600 Brinell hardness, is formed along the string. NB: (i) The screw threadsi 3b (of the pin tool joint 13c) are not hardened.
(ii) The outer layer of the recesses 13d, engageable by uncoupling tools, are preferably hardened (eg to a 6.0mm thickness) to a hardness greater than 4140 pipe, but less than the at least 600 Brinell hardness of the 5 layer 13a.
The hardness of the outer layer of the recesses 13d may be in the range of 280-500 Brinell.
The method of effecting the hardening of the layer 13a will now be described. o The drill steel 13, of 4140 material for the tool joints and the connecting pipe, is supported in a long (eg. 12m bed) lathe 20 by gripping one end with a chuck 21 and supporting the other by a chuck or a tailstock 22.
The induction heating and quenching unit 30 is hollow and passes s about the drill steel 13.
The induction heating and quenching unit 30 is mounted on the lathe carriage 23 and its rate of advance along the lathe 20 is controlled by a feed screw 24.
An induction heating head 31 is connected to a high frequency o electrical power source 32 via suitable power cables 33, and closely surrounds the pipe 13.
The quenching head 34 is located adjacent to, and downstream of, the induction heating head 31 , and is connected to a source of quenching liquid (not shown) by suitable pipes 35. The drill steel 13 is heated by electrical induction generated by the induction heating head 31. A current is oscillated at high frequencies through the pipe wall or tool joint. The resistance of the material to the electron flow converts the electrical energy into heat, which is closely regulated and monitored by optical pyrometers 36 mounted on the unit 30. The relative speed of the drill steel 13 passing through the induction heating head 31 , and the power applied, is precisely controlled to achieve heat balance at the required temperature.
The drill steel 13 is then subjected to quenching in the quenching head 34 to achieve the desired hardness and depth of hardness. The induction head 34 has quenching sprays 37, integral to the head 34, directing quenching liquid onto the drill steel 13.
A potential problem in the process could be the drill steel 13 bending as it is heated and quenched. To limit this bending, the drill steel 13 can be rotated as the induction heating and quenching unit 30 is passed over it - this will tend to evenly distribute the heating and quenching around the drill steel 13. If the drill steel 13 does bend, it is proposed to either hydraulically straighten the drill steel or spot heat the drill steel to straighten it.
The induction hardening method need not be limited to drill steels, as other drill string components, such as bit subs and stabilisers may be hardened as well.
One of the problems of hardening complete drill strings is that when drill string components are uncoupled, using a hydraulic pipe wrench fitted standard to the drill, the break-out dies in the wrench that grip the drill steel need to be harder than the drill steel it is attempting to grip. If the dies are softer or the same hardness, they will not bite into the steel and the drill steel will slip on the dies. This would make uncoupling very difficult. It is proposed to overcome this problem by induction hardening the region(s) eg recesses 13d, on the drill steel 13 that are gripped by the pipe wrench. The hardening process will be modified for these region(s) to ensure they are softer than the rest of the induction hardened material 13a. The softer outer layers of the recess 13d will still be harder than standard quenched and tempered 4140 material, but not too hard that the dies will not grip. (The "softer" outer layers of the recess 13d are preferably hardened, eg., in the range of 280-500 Brinell.)
It will be readily apparent to the skilled addressee that the extended service life of the drill string components, and the drill strings incorporating same, manufactured by the method of the present invention, whilst possibly having a higher initial capital outlay, will result in considerable savings over the life of the drill strings.
Various changes and modifications may be made to the embodiment described and illustrated without departing from the present invention.

Claims

CLAIMS:
1. A method of induction hardening a drill steel, including the steps of: supporting the drill steel to be hardened in a support member; placing a hollow induction heating head and a hollow quenching head about the drill steel; advancing the induction heating head along the drill steel to heat an outer layer on the drill steel; and advancing the quenching head along the drill steel, to quench the outer layer of the drill steel to above the desired hardness and depth of hardness.
2. A method as claimed in claim 1 , wherein: the induction heating head and the quenching head are provided in a combined unit.
3. A method as claimed in claim 1 or claim 2, wherein: the drill steel is manufactured from AISI 4140 material, and the outer layer of the material is hardened to a depth of at least 6mm, and to a hardness of at least 600 Brinell.
4. A method as claimed in claim 1 , wherein: the support member is a lathe or other suitable support structure operable to rotate the drill steel as the induction heating head and the quenching head are advanced.
5. A method as claimed in claim 1 , wherein: the temperature of the drill steel is closely monitored by one or more optical pyrometers during the heating step.
6. A method as claimed in claim 3, wherein: where region(s) of the drill steel are to be engaged by tools, for uncoupling, an outer layer of the material in the region(s) hardened to a lower Brinell hardness.
7. A method as claimed in claim 6 hwerein: the lower Brinell hardness is in the range of 280 to 500.
8. A drill steel, or other drill string component, hardened by the method, of any one of claims 1 to 7.
9. A drill string incorporating one or more drill steels or drill string components, hardened by the method of any one of claims 1 to 7.
PCT/AU2005/001777 2004-11-23 2005-11-23 Induction-hardened drill string components WO2006056010A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AU2004906674A AU2004906674A0 (en) 2004-11-23 Induction-hardened drill string components
AU2004906674 2004-11-23

Publications (1)

Publication Number Publication Date
WO2006056010A1 true WO2006056010A1 (en) 2006-06-01

Family

ID=36497668

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/AU2005/001777 WO2006056010A1 (en) 2004-11-23 2005-11-23 Induction-hardened drill string components

Country Status (1)

Country Link
WO (1) WO2006056010A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120186320A1 (en) * 2011-01-21 2012-07-26 Moshe Israel Meidar Method and machine tool for the processing and hardening of metallic workpieces
CN107630138A (en) * 2017-09-13 2018-01-26 中国地质大学（武汉） The device for magnetic treatment and method that a kind of hot pressing coring formula iron base diamond drilling bit is modified

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4046603A (en) * 1974-07-05 1977-09-06 Mannesmann Aktiengesellschaft Process for the continuous hardening of tubes
US4844752A (en) * 1985-10-23 1989-07-04 Quinn's Oilfield Supply Ltd. Process for making internally hardened tubes
US5433800A (en) * 1987-08-17 1995-07-18 Arthur E. Bishop & Associates Pty, Ltd. Scanning induction hardening
US6048417A (en) * 1996-08-16 2000-04-11 Caterpillar Inc. Method and apparatus for heat treating a bushing
WO2003097885A1 (en) * 2002-05-17 2003-11-27 Sandvik Ab Rock drill product and method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4046603A (en) * 1974-07-05 1977-09-06 Mannesmann Aktiengesellschaft Process for the continuous hardening of tubes
US4844752A (en) * 1985-10-23 1989-07-04 Quinn's Oilfield Supply Ltd. Process for making internally hardened tubes
US5433800A (en) * 1987-08-17 1995-07-18 Arthur E. Bishop & Associates Pty, Ltd. Scanning induction hardening
US6048417A (en) * 1996-08-16 2000-04-11 Caterpillar Inc. Method and apparatus for heat treating a bushing
WO2003097885A1 (en) * 2002-05-17 2003-11-27 Sandvik Ab Rock drill product and method

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120186320A1 (en) * 2011-01-21 2012-07-26 Moshe Israel Meidar Method and machine tool for the processing and hardening of metallic workpieces
CN107630138A (en) * 2017-09-13 2018-01-26 中国地质大学（武汉） The device for magnetic treatment and method that a kind of hot pressing coring formula iron base diamond drilling bit is modified
CN107630138B (en) * 2017-09-13 2019-02-12 中国地质大学（武汉） A kind of magnetic processing device and method that hot pressing coring formula iron base diamond drilling bit is modified

Similar Documents

Publication Publication Date Title
US9488008B2 (en) Downhole assembly, tool and method
US7814991B2 (en) Process and apparatus for subterranean drilling
US7237628B2 (en) Fixed cutter drill bit with non-cutting erosion resistant inserts
US6766870B2 (en) Mechanically shaped hardfacing cutting/wear structures
US10480249B2 (en) Hybrid mechanical-laser drilling equipment
US9464484B2 (en) Hydraulic percussion apparatus and method of use
US9133667B2 (en) Drill bit for boring earth and other hard materials
US8720607B2 (en) Downhole tool having a friction stirred surface region
US20160090824A1 (en) Downhole tools having hydrophobic coatings, and methods of manufacturing such tools
WO2006056010A1 (en) Induction-hardened drill string components
CN101644136B (en) Combination of reaming stabilizer and bottom drilling device
US20140008129A1 (en) Multidirectional wellbore penetration system and methods of use
Bondarenko ISM high-performance tools for drilling of oil and gas wells. Review
US10704333B2 (en) Metal matrix composite drill bits with reinforcing metal blanks
JPT staff Hybrid rotary steerable system delivers higher build rates and smoother holes
US8307920B2 (en) Roller cone disk with shaped compacts
CONSUMABLES Product Catalog
CN210714478U (en) Safety long-life roller bit
US6978852B2 (en) Rock drill product and method
CN205577857U (en) Down --hole drill bit
CN205743752U (en) A kind of wear-resistant centralizer for screwdrill
US11136830B2 (en) Downhole tools with variable cutting element arrays
Rejepovich TECHNOLOGICAL AND TECHNICAL PROBLEMS ASSOCIATED WITH THE WIRING OF HORIZONTAL WELLS WITH AN ELECTOBUR AND WAYS TO SOLVE THEM
US5586610A (en) Kelly bar having hardened flutes
WO2023230402A1 (en) Wear resistant tubular members and systems and methods for producing the same

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KM KN KP KR KZ LC LK LR LS LT LU LV LY MA MD MG MK MN MW MX MZ NA NG NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU LV MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 05804569

Country of ref document: EP

Kind code of ref document: A1