The present disclosure is directed to a pipe management system and, more particularly, is directed to a pipe management system for negative angle drilling.
Excavating is employed to create mines, quarries, etc., in order to obtain desirable material such as ore or stone. In addition to using various types of heavy excavating equipment, drill-and-blast operations are commonly used to fragment material so it can be loaded and hauled. For example, overburden may need to be removed in order to reach the desirable material. Drill-and-blast operations may include drilling different types of blast holes, and some blast holes, for example pre-split holes, may require negative angle drilling. For example, pre-split holes are drilled in a “bench” of an excavation typically at an angle, referred to as a “negative angle,” that aligns with the slope of a “highwall” of the excavation, for example 5 to 15 degrees from a vertical direction.
Current drill-and-blast operations employ platform based drills to bore production holes, but not for boring pre-split holes which must be formed close to the highwall and substantially at the negative angle of the highwall in order to maintain the desired slope of the highwall as the depth of the bench is increased and the height of the highwall is increased. Since current platform based drills are not capable of drilling at the required negative angle of the highwall, the usual drill-and-blast operation will employ various dedicated pre-split drills that are usually boom mounted drills. Accordingly, a drill-and-blast operation in an open pit mine ordinarily may require a diverse fleet of drilling machines in order to form the different types of required holes.
During a drilling operation with a platform based drill, sections of drill pipe may be added to a drill column in order to increase the depth of drilling, and later removed as the drill column is disassembled. Various systems for managing drill pipe have been developed to manipulate and stabilize the drill pipe both during drilling and when adding or removing sections of drill pipe. Such drill pipe management systems typically include pipe handling equipment that requires substantial space, either externally of the mast or within the mast. Platform based drills capable of drilling blast holes at negative angles may enable drilling of all the various types of blast holes, including production and pre-split holes. Drilling negative angle holes with an open side of the mast inclined downwardly presents pipe management issues, particularly since gravity tends to work against pipe alignment as the mast tilts to negative angles. Current pipe management systems have not proven adequate for negative angle drilling.
There exists a need for a relatively simple and cost-effective pipe management system that occupies minimum space and effectively handles drill pipe as it is installed and removed from the drill column. It would be both beneficial and desirable to provide the mast of a drilling machine capable of negative angle drilling with a system that will both occupy minimum space and support negative angle drilling and that can hold and maintain drill pipe stable during both positive and negative angle drilling as well as vertical drilling. It would be both beneficial and desirable to provide a platform based drill that is capable of boring both vertical and positive angle production holes, is capable of boring negative angle pre-split holes, and includes support structure sufficient to accommodate pipe handling and management with a mast tilted at a negative angle.
One type of drilling machine used for drill and blast operations is disclosed in U.S. Pat. No. 5,931,238 issued to Gilmore et al. on Aug. 3, 1999 (“the '238 patent”). The '238 patent discloses a blast hole drill with a drill head mounted on a mast and a pipe carousel on the drill deck. A drill pipe handling system includes an arm assembly that transfers a drill pipe from a position on a pipe carousel to a position adjacent the mast. The arm assembly includes a single jaw pipe grasping assembly and a double jaw grasping assembly to hold a drill pipe as it is transferred by the arm assembly.
While the drilling machine of the '238 patent may be useful for some drilling purposes, the '238 patent does not disclose a pipe management system that supports negative angle drilling. In addition, the drill pipe handling system disclosed in the '238 patent may be unduly complicated and adapted only to drilling machines where drill pipes are stored in horizontal position on the deck. Furthermore, the drill pipe handling system disclosed in the '238 patent requires a substantial amount of space in order to manipulate between a pipe loading and pipe storage position. Accordingly, the system of the '238 patent may not be suitable for drilling operations where the pipe carousel is positioned parallel to the mast.
The disclosed pipe management system for negative angle drilling of the present disclosure solves one or more of the problems set forth above and/or other problems of the prior art.
In one aspect, the present disclosure is directed to a pipe handling system for a platform based drill comprising a drilling platform including a frame structure having a first end, a second end opposite the first end, and first and second opposite sides. The pipe handling system for a platform based drill may include a mast supported on a pivotal connection to the drilling platform permitting the mast to be pivotally adjusted to a negative drilling angle whereby an upper portion of the mast leans in a first direction extending toward the first end of the frame structure and away from the second end of the frame structure, the mast including a length direction and having an open cross-section with a concave side facing in the first direction, and a convex side facing in a second direction opposite to the first direction. The pipe handling system also may include a pipe handling unit mounted to the concave side of the mast and configured to support a drill pipe within the mast when the mast is pivotally adjusted to the negative drilling angle.
In another aspect, the present disclosure is directed to a pipe handling unit on a mast of a drilling platform and may include a mast having a length direction and a generally C-shaped cross section including a back element and first and second side elements partially enclosing a space within the mast, and including an open front. The pipe handling unit may be within the space and may include a first support linkage having first and second ends and pivotally attached at the first end to the first side element, and a second support linkage having first and second ends and pivotally attached at the first end to the second side element.
In yet another aspect, the present disclosure is directed to a method of managing drill pipe to support negative angle drilling with a drilling machine including a mast having a length direction and a generally C-shaped cross section with a back element and first and second side elements partially enclosing a space, and including an open front. The method may include pivoting the mast to a negative angle with the mast leaning from a vertical direction toward the direction of the open front and away from the back element. The method also may include moving in the length direction of the mast a pair of opposed arcuate support elements that are partially cylindrical about axes extending parallel to the length direction of the mast. The method also may include, while moving the pair of opposed arcuate support elements, maintaining the axes extending parallel to the length direction of the mast to engage and support a section of drill pipe. The method also may include moving the pair of opposed arcuate support elements again in the length direction of the mast. The method also may include, while moving the pair of opposed arcuate support elements again, maintaining the opposed arcuate support elements parallel to the length direction of the mast to release the section of drill pipe.
During the course of forming excavation 10, bench 12 may be drilled and blasted in order to aid further removal of overburden and/or desirable ore material, for example. A common practice is to attempt to maintain face 15 of highwall 14 at an angle α relative to vertical direction 17 that is commensurate with maintaining stability of highwall 14. For example, an exemplary angle α of slope for face 15 of highwall 14 may be on the order of 15 degrees from vertical direction 17. Mast 30 may be supported and mounted for pivotal movement adjacent first end 32 and adjacent a lower portion 29 of mast 30, permitting mast 30 to be pivotally adjusted to a negative drilling angle equivalent to angle α whereby an upper portion 31 of mast 30 leans in a first direction extending toward first end 32 of frame structure 20 and away from second end 34 of frame structure 20.
As illustrated in
A pipe rack carousel 62 may be suitably mounted adjacent mast 30 and may include holders 63 for a plurality of drill pipe sections, such as drill pipe section 66 illustrated at drill column 65. Pipe rack carousel 62 may be mounted to swing about a pivot rod 64, for example mounted to baseplate 60 of mast 30, to move a drill pipe section 66 to or from drill column 65. Pipe rack carousel 62 is illustrated in
First support linkage 52 may include first arm 75 and second arm 76 spaced from each other along length direction A of mast 30 with first arm 75 being parallel to second arm 76. Similarly, second support linkage 56 may include first arm 77 and second arm 78 spaced from each other along length direction A of mast 30 with first arm 77 being parallel to second arm 78. A first mast bracket 79 and a first support element bracket 80 may be associated with first support linkage 52 and its first and second arms 75, 76. Similarly, a second mast bracket 81 and a second support element bracket 82 may be associated with second support linkage 56 and its first and second arms 77, 78. First mast bracket 79 may be fixed to first side element 44 on concave side 38 of mast 30. In like manner, second mast bracket 81 may be fixed to second side element 46. First support element bracket 80 may be fixed to first arcuate support element 72, and second support element bracket 82 may be fixed to second arcuate support element 74. First and second arms 75, 76 of first support linkage 52 may be pivotally connected to first mast bracket 79 via pivotal connections 83, 84 at first end 53 of first support linkage 52, and may be pivotally attached to first support element bracket 80 via pivotal connections 87, 88 at second end 54 of first support linkage 52. First and second arms 77, 78 of second support linkage 56 may be pivotally connected to second mast bracket 81 via pivotal connections 85, 86 at first end 57 of second support linkage 56, and may be pivotally attached to second support element bracket 82 via pivotal connections 89, 90 at second end 55 of second support linkage 56.
One of first and second arms 75, 76, for example second arm 76, of first support linkage 52, and one of first and second arms 77, 78, for example second arm 78, of second support linkage 56, may include an aperture 97, 98 for connection of a suitable actuator, for example a hydraulic cylinder. First and second actuators 40, 41, not shown in
As will be apparent from the foregoing description and
As more clearly illustrated in
The disclosed pipe management system for negative angle drilling facilitates handling of drilling pipe in a platform based drill where a mast is capable of being pivoted to a negative angle for negative angle drilling. The disclosed open cross-section mast having the concave open side facing in the same direction that the mast leans during negative angle drilling is made more feasible and cost effective by being provided with the disclosed drill pipe handling system. While gravity tends to work with drill pipe when drilling vertically, gravity works against drill pipe during negative angle drilling by pulling it toward the open or concave side of the mast, particularly during loading drill pipe sections into the drill column and removing drill pipe sections from the drill column.
Advantageously, the disclosed pipe management system for negative angle drilling operates to fully support drill pipe and maintain it in alignment with the drill hole associated with the mast. In addition, the disclosed pipe management system for negative angle drilling facilitates loading and unloading drill pipe sections between the drill column and the carousel. The pipe handling unit is housed entirely within the mast itself and occupies a minimum of space thereby avoiding interference with other components associated with the mast. Also, the movement of the pipe handling unit along the length direction of the mast via a parallelogram linkage assembly involves a minimum of movement from a position engaging a drill pipe section to a disengaged position, and therefore requires less space for movement.
An exemplary method according to the disclosure of managing drill pipe to support negative angle drilling with a drilling machine including a mast having a length direction and a generally C-shaped cross section with a back element and first and second side elements partially enclosing a space and including an open front, is diagrammatically illustrated via flowchart 100 in
At box 104, a pair of opposed arcuate support elements that are partially cylindrical about axes extending parallel to the length direction of the mast are moved in the length direction of the mast. At box 106, while moving the pair of opposed arcuate support elements, the axes are maintained extending parallel to the length direction of the mast to engage and support a section of drill pipe. At box 108, the pair of opposed arcuate support elements again are moved in the length direction of the mast. At box 110, while moving the pair of opposed arcuate support elements again, the axes are maintained extending parallel to the length direction of the mast to release the section of drill pipe.
For each moving of the pair of opposed arcuate support elements in the length direction of the mast, at box 112, parallel arms for each of the pair of opposed arcuate support elements may be moved, the parallel arms being attached to one of the first and second side elements of the mast at a first end of the arms and connected to the arcuate support elements at a second end of the arms. The mast may include a baseplate with a drill hole, and, at box 114, the section of drill pipe may be supported and maintained in alignment with the drill hole with the pair of opposed arcuate support elements. At box 116, each moving of the pair of opposed arcuate support elements in the length direction of the mast to support and release the section of drill pipe may be coordinated with loading and unloading the section of drill pipe from a pipe rack carousel and with operation of a deck wrench.
Use of the terms “substantially” and “generally” within this specification, (e.g., substantially parallel, generally C-shaped, etc.) is intended to take into account those situations wherein the components and relationships referenced may deviate from an absolute by normal and accepted convention, industry manufacturing tolerances, or industry field tolerances.
It will be apparent to those skilled in the art that various modifications and variations can be made in the disclosed pipe management system for negative angle drilling without departing from the scope of the disclosure. Other embodiments of the disclosed pipe management system for negative angle drilling will be apparent to those skilled in the art from consideration of the specification. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims and their equivalents.