Arrangement for controlling collaring drilling

Abstract

An apparatus for controlling collaring drilling includes at least one collaring cycle executed in a control device. The collaring cycle has an advance drilling step, a reversing step and a monitoring feature. The apparatus is configured to repeat as many collaring cycles as needed for reaching a drilled material having predetermined properties. The disclosure also relates to a method for collaring drilling and a computer program product.

1 . An apparatus for controlling collaring drilling, wherein the collaring drilling includes initiating drilling of a drill hole followed by actual drilling for drilling the drill hole to a final drilling depth, the apparatus comprising at least one control device arranged to control a drilling unit during the collaring drilling by executing at least one collaring cycle in the control device, the collaring cycle including an advance drilling step and a defined advance rule, whereby the apparatus is configured to control the drilling unit to advance the drilling of the drill hole in a drilling direction from a realized depth of the drill hole further to a next depth, the collaring cycle defining a reversing step executed in response to a success of the defined advance rule, whereby the apparatus is configured to terminate the advance drilling and move the drilling tool in a reverse direction, the collaring cycle further including a monitoring feature for controlling the apparatus to receive measuring data from the drilling unit and to monitor characteristics of the drilled material during the advance drilling, and wherein the apparatus is configured to execute several collaring cycles successively at least until a change in the monitored characteristics during the advance drilling is detected, whereby the number of the executed collaring cycles of the drill hole under examination is dependent on the characteristics of the drilled material. 
     
     
         2 . The apparatus as claimed in  claim 1 , wherein the apparatus is configured to detect initial depth position of the collaring drilling corresponding to an opening of the drill hole being drilled, and further detect a greatest depth of the drill hole corresponding a bottom of the drill hole, the apparatus being configured to reverse the drilling tool during the reversing step of the collaring cycle out of the drill hole, whereby the reversing step defines the reversing movement from the bottom of the drill hole at least to the opening of the drill hole. 
     
     
         3 . The apparatus as claimed in  claim 1 , wherein the apparatus is configured to control the drilling unit to direct flushing flow through a drilling tool to the drill hole during the collaring cycle, the apparatus being configured to increase magnitude of the flushing flow in response to an increase of the drilling depth, whereby the flushing flow is greater during every following collaring cycle compared to the previous collaring cycles. 
     
     
         4 . The apparatus as claimed in  claim 2 , wherein the apparatus is configured to terminate the flushing flow during the reversing step of the collaring cycle at a distance from the opening of the drill hole, whereby the flushing flow is terminated before a drilling tool is pulled out of the drill hole. 
     
     
         5 . The apparatus as claimed in  claim 1 , wherein the apparatus is configured to control the drilling unit to direct liquid flow through a drilling tool to the drill hole during the reversing step of the collaring cycle. 
     
     
         6 . The apparatus as claimed in  claim 1 , wherein the apparatus is configured to delay the execution of the succeeding collaring cycles. 
     
     
         7 . The apparatus as claimed in  claim 6 , wherein the apparatus is configured to delay the execution of the succeeding collaring cycles for a duration of a determined delay time. 
     
     
         8 . The apparatus as claimed in  claim 1 , wherein the apparatus is provided with reference data defining at least one limit value for determining difference in hardness of loose drilled material and solid drilled material, the apparatus being configured to control collaring drilling through a loose material layer towards a solid material layer, detect change in drilling characteristics by means of the comparison of the measuring data and the limit value when reaching the solid material layer during the advance drilling, and to determine depth position of the solid material layer on the basis of the detected change in drilling characteristics at a borderline between the loose material layer and the solid material layer. 
     
     
         9 . The apparatus as claimed in  claim 8 , wherein the apparatus is provided with data on depth of solid material layer of at least one drill hole being located at proximity of the drill hole under examination, the apparatus being configured to determine depth of solid material layer of the drill hole under examination on the basis of the determined characteristics of the material, and to compare the determined depth of the solid material layer of the drill hole under examination to the depth of the solid material of the at least one neighboring drill hole in order to improve accuracy of the determination of the depth position of the solid material layer. 
     
     
         10 . The apparatus as claimed in  claim 8 , wherein the apparatus is provided with data on thickness of the loose material layer and based on that is configured to estimate depth position of a borderline between the loose and solid material layer, the apparatus being configured to compare the determined depth position to the estimate depth position in order to improve accuracy of the determination of the depth position of the solid material layer. 
     
     
         11 . The apparatus as claimed in  claim 1 , wherein the apparatus is provided with data on feed resistance of the feed device of the drilling unit during advance drilling of the collaring cycle, the apparatus being configured to compare the data with at least one limit value for the feed resistance for detecting hardness of the drilled material. 
     
     
         12 . The apparatus as claimed in  claim 11 , wherein the apparatus is provided with pressure data on the pressure fluid operated feed device of the drilling unit, the limit value includes a threshold pressure, whereby exceeding the threshold pressure indicates change in characteristics of the drilled material. 
     
     
         13 . The apparatus as claimed in  claim 1 , wherein the apparatus is provided with data on stress waves propagating in a drilling tool of the drilling unit, which is provided with an impact device for generating stress waves to the drilling tool and the stress waves reflecting back from the drilled material towards the rock drilling machine in accordance with the hardness of the drilled material, the apparatus being configured to compare the data with at least one limit value for the magnitude of the reflecting stress waves for detecting characteristics of the drilled material. 
     
     
         14 . The apparatus as claimed in  claim 1 , wherein the apparatus is configured to control the drilling unit to execute transfer drilling of the drilling tool from a reversed drill hole depth position to the realized drill hole bottom reached in the previous collaring cycle before initiating advance drilling of the following collaring cycle, the apparatus being configured to connect the rock drilling machine on during the transfer drilling. 
     
     
         15 . The apparatus as claimed in  claim 1 , wherein the advance rule of the collaring cycle defines an advance distance, whereby the apparatus is configured to control the drilling unit to advance the drilling of the drill hole in the drilling direction further for the length of the defined advance distance. 
     
     
         16 . The apparatus as claimed in  claim 1 , wherein the advance rule of the collaring cycle defines an advance period of time, whereby the apparatus is configured to control the drilling unit to advance the drilling of the drill hole in the drilling direction until the defined advance period of time expires. 
     
     
         17 . The apparatus as claimed in  claim 1 , wherein the collaring cycle defines a reverse distance or period of time for the reversing step, whereby the apparatus is configured to move the drilling tool in a reverse direction for the defined reverse distance or period of time. 
     
     
         18 . A rock drilling rig, comprising
 a movable carrier;   at least one drilling boom provided with at least one drilling unit including a rock drilling machine and a feed device for moving the rock drilling machine; and   at least one apparatus for controlling drilling, wherein the collaring drilling includes initiating drilling of a drill hole followed by actual drilling for drilling the drill hole to a final drilling depth, the apparatus including at least one control device arranged to control a drilling unit during the collaring drilling by executing at least one collaring cycle in the control device, the collaring cycle including an advance drilling step and a defined advance rule, whereby the apparatus is configured to control the drilling unit to advance the drilling of the drill hole in a drilling direction from a realized depth of the drill hole further to a next depth, the collaring cycle defining a reversing step executed in response to a success of the defined advance rule, whereby the apparatus is configured to terminate the advance drilling and move the drilling tool in a reverse direction, the collaring cycle further including a monitoring feature for controlling the apparatus to receive measuring data from the drilling unit and to monitor characteristics of the drilled material during the advance drilling, and wherein the apparatus is configured to execute several collaring cycles successively at least until a change in the monitored characteristics during the advance drilling is detected, whereby the number of the executed collaring cycles of the drill hole under examination is dependent on the characteristics of the drilled material.   
     
     
         19 . A method for collaring drilling, wherein drilling of a drill hole is initiated by a drilling unit including a rock drilling machine movable by a feed device and being provided with a drilling tool, the method comprising the steps of:
 controlling the drilling unit with at least one control device;   providing the control unit with at least one collaring cycle;   executing the collaring cycle in the control device for controlling the collaring drilling;   drilling in a drilling direction a predetermined limited advance distance or limited period of time defined in the collaring cycle and monitoring simultaneously the drilling;   stopping the advance drilling when the limited advance distance is reached or the limited period of time is expired and moving the drilling tool in a reverse direction;   detecting change in the drilled material on the basis of the monitored data; and   executing several collaring cycles one after each other until the change in the drilled material is being detected by the control device and final depth of the collaring drilling is reached.   
     
     
         20 . A computer program product comprising program code means configured to execute the steps and procedures of  claim 20  when being run on a computer or a data processing device.