Drill rod clamping system and methods of using same

Patent metadata

Field	Value
Publication number	US-10066451-B2
Application number	US-201615387981-A
Country	US
Kind code	B2
Filing date	Dec 22, 2016
Priority date	Dec 22, 2015
Publication date	Sep 4, 2018
Grant date	Sep 4, 2018

Abstract

A drill rod clamping system for securing a drill rod in a selected position. The drill rod clamping system has a hollow spindle with an upper portion that defines axial slots and a base portion that defines at least one radial opening. A plurality of jaws are moveable radially inwardly to a drill rod gripping position and radially outwardly to a drill rod releasing position. Each jaw is received within a respective axial slot of the hollow spindle. An actuator moves the plurality of jaws between the drill rod gripping position and the drill rod releasing position. A compressed gas spring assembly exerts force on the actuator to close the jaws. A hydraulic operator exerts force on the actuator to overcome the force of the compressed gas spring assembly to open the jaws. The radial openings of the base portion of the spindle permit flushing of material flowing within the spindle.

First claim

What is claimed is:

1. A drill rod clamping system for securing a drill rod in a selected position, the drill rod clamping system having a longitudinal axis and comprising:
a hollow spindle having a central bore, an inner surface, an outer surface, a base portion and an upper portion extending upwardly from the base portion relative to the longitudinal axis, wherein the upper portion defines a plurality of axial slots that extend between the inner and outer surfaces of the hollow spindle, and wherein the base portion defines at least one opening that extends between the inner and outer surfaces of the hollow spindle;
a plurality of jaws coupled to the spindle and being moveable radially inwardly to a closed drill rod gripping position and radially outwardly to an open drill rod releasing position, wherein each jaw is at least partially received within a respective axial slot of the plurality of axial slots of the upper portion of the hollow spindle;
an actuator configured to move the plurality of jaws between the closed drill rod gripping position and the open drill rod releasing position;
a compressed gas spring assembly configured to exert sufficient force on the actuator to close the jaws of the drill rod clamping system, the compressed gas spring assembly comprising a plurality of compressed gas springs, wherein each compressed gas spring comprises a cylinder containing compressed gas and a piston urged by the compressed gas outwardly of the cylinder to the end of its stroke; and
a hydraulic operator configured to exert force on the actuator to overcome the force of the compressed gas spring assembly to effect opening of the jaws of the drill rod clamping system,
wherein the at least one opening of the base portion of the hollow spindle is configured to permit flushing of material flowing within the central bore of the hollow spindle relative to the longitudinal axis.

2. The drill rod clamping system of claim 1 , wherein each jaw of the plurality of jaws is mounted within a respective axial slot of the plurality of axial slots of the upper portion of the hollow spindle.

3. The drill rod clamping system of claim 1 , wherein the actuator comprises a jaw bowl that is slideable relative to the plurality of jaws to open and close the jaws, wherein the jaw bowl has an upper surface, and wherein the cylinders of the compressed gas springs of the compressed gas spring assembly are embedded in the upper surface of the jaw bowl.

4. The drill rod clamping system of claim 3 , further comprising a gas spring retainer that circumferentially surrounds the hollow spindle and at least partially encloses the compressed gas springs, wherein the gas spring retainer has an inner stop surface, and wherein the pistons of the compressed gas springs of the compressed gas spring assembly are configured to engage the stop surface to urge the actuator away from the stop surface to the jaw closing position.

5. The drill rod clamping system of claim 4 , further comprising a base plate secured to the base portion of the spindle, wherein the base plate defines a central opening positioned in alignment with the central bore of the spindle, and wherein the base plate extends radially outwardly from the outer surface of the base portion of the spindle.

6. The drill rod clamping system of claim 4 , wherein the jaw bowl has jaw receiving undercut slots for registering with the axial slots in the upper portion of the spindle, and wherein the jaws project through the spindle slots into the central bore of the spindle to grip a drill rod and to be withdrawn from the drill rod gripping position upon sliding motion of the jaw bowl.

7. The drill rod clamping system of claim 6 , further comprising a jaw retainer having depending legs projecting downwardly for complementary receipt within the axial slots of the spindle to overlie the jaws and prevent upward movement thereof.

8. The drill rod clamping system of claim 7 , further comprising a bushing positioned at least partially within the spindle and overlying the plurality of jaws, wherein the bushing is configured to allow the jaws to move radially inwardly to a closed drill rod gripping position and radially outwardly to an open drill rod releasing position.

9. The drill rod clamping system of claim 8 , wherein the bushing is a split bushing comprising at least two pieces that are configured to be selectively secured to the jaw retainer to cooperatively form a circumferential enclosure.

10. A drill rod clamping system of claim 6 , wherein the jaw bowl has an inner surface, an outer surface, and at least one radial grease feed passageway extending between the inner and outer surfaces of the jaw bowl and positioned in communication with the jaw receiving slots.

11. A drill rod clamping system of claim 10 , wherein the jaw bowl defines a circumferential grease passageway, and wherein the jaw receiving slots are interconnected by the circumferential grease passageway.

12. A drill rod clamping system of claim 6 , wherein the jaw receiving slots of the jaw bowl and the plurality of jaws have complementary engagement portions, wherein downward movement of the jaw bowl positively advances the jaws into the drill rod gripping position, and wherein upward movement of the jaw bowl positively withdraws the jaws from the drill rod gripping position.

13. A drill rod clamping system of claim 12 , further comprising a plurality of locating pins that are interposed between the jaw bowl and the gas spring retainer to locate the jaw bowl so that the jaw receiving slots complementarily register with the axial slots in the top portion of the spindle.

14. A drill rod clamping system of claim 13 , wherein the jaws comprise grippers that are configured to grip a drill rod.

15. The drill rod clamping system of claim 14 , wherein the grippers have an angled tooth pattern, and wherein the angled tooth pattern comprises a plurality of teeth that have respective plough paths through rod material when gripping the drill rod.

16. The drill rod clamping system of claim 4 , wherein the gas springs are configured to effect downward movement of the jaw bowl, and wherein the hydraulic operator is configured to effect upward movement of the jaw bowl.

17. The drill rod clamping system of claim 4 , wherein the drill rod clamping system does not rotate.

18. The drill rod clamping system of claim 4 , wherein, upon deactivation of the hydraulic operator, the force exerted by the hydraulic operator on the actuator is removed to allow the compressed gas spring assembly to drive the plurality of jaws to the drill rod gripping position.

19. The drill rod clamping system of claim 4 , wherein the actuator comprises an inner ring cylinder that circumferentially surrounds the base portion of the spindle, an outer ring cylinder that circumferentially surrounds the inner ring cylinder, and a ring cylinder piston positioned radially between the inner and outer ring cylinders, wherein the ring cylinder piston is configured for upward and downward movement relative to the longitudinal axis to selectively engage the gas springs.

20. The drill rod clamping system of claim 19 , further comprising a ring cylinder cover positioned between the actuator and the jaw bowl, wherein the ring cylinder cover circumferentially surrounds the spindle and is configured to direct material radially inwardly and away from the ring cylinder piston.

21. The drill rod clamping system of claim 19 , wherein the actuator is selectively replaceable independently of the other co

Assignees

• Bly Ip Inc

Inventors

• Ritter David Robert
• Wright Christopher Allen
• Markham Anthony Charles William

Classifications

• E21B17/042

  Threaded · CPC title

• E21B17/1042

  Elastomer protector or centering means · CPC title

• E21B19/163

  piston-cylinder actuated · CPC title

• E21B19/07 Primary

  Slip-type elevators · CPC title

• E21B19/24

  Guiding or centralising devices for drilling rods or pipes · CPC title