Drill string for a sonic drill rig

Abstract

The invention relates to a drill string for a sonic drill rig, which drill string comprises a number of drill pipes, each drill pipe having on one end a male connection and on the other end a female connection, wherein the male connection and female connection of two adjacent drill pipes form a joint to connect the respective drill pipes together and to form a string, wherein each drill pipe is provided with an RFID tag containing a code unique to the drill pipe, wherein the RFID tag is arranged in a cavity provided in the drill pipe, wherein the RFID tag of each drill pipe is embedded in a solidified fluid, such as a synthetic resin, filling the cavity and wherein the cavity and resin have a form-fit connection.

Description

[0001] Drill string for a sonic drill rig

[0002] The invention relates to a drill string for a sonic drill rig, which drill string comprises a number of drill pipes , each drill pipe having on one end a male connection and on the other end a female connection, wherein the male connection and female connection of two adj acent drill pipes form a j oint to connect the respective drill pipes together and to form a string, wherein each drill pipe is provided with an RFID tag containing a code unique to the drill pipe , wherein the RFID tag is arranged in a cavity provided in the drill pipe .

[0003] Such a drill string is for example known from US 2012212326 .

[0004] The application of such a drill string in a sonic drill string subj ects the RFID tag and the attachment thereof to the drill pipe to severe conditions . The vibrations of the sonic drill head will be transmitted to the mounting of the RFID tag, which could result in detachment of the RFID tag from the drill pipe . The RFID tag will then be lost into the ground, in which the drill string is drilled .

[0005] Accordingly, it is an obj ect to reduce or even remove the above mentioned disadvantages .

[0006] This obj ect is achieved according to the invention with a drill string according to the preamble , which is characteri zed in that the RFID tag of each drill pipe is embedded in a solidi fied fluid, such as a synthetic resin, filling the cavity and wherein the cavity and resin have a form- fit connection .

[0007] By embedding the RFID tag in a solidi fied fluid, which fills the cavity, an easy and cost ef fective form- fit connection is obtained . I f the solidi fied fluid would detach from the wall of the cavity due to the continued vibrations of the sonic drill head, the form- fit connection will still keep the RFID tag inside of the cavity . This ensures that the RFID tag will be brought up with the drill pipe after drilling and could be reattached into the cavity .

[0008] In a preferred embodiment of the drill string according to the invention the cavity of each drill pipe is arranged in the outer circumferential surface of the drill pipe and wherein the cavity extends from the circumferential surface into the body of the drill pipe along a main axis .

[0009] With the RFID tag in a cavity in the outer circumferential surface , the RFID tag can easily be read, while the drill tube is mounted on the drill string and push into the ground . For example the antenna of a RFID scanner could be positioned around an opening in the drill rig, through which opening the drill string is transported and push into the ground .

[0010] In a further preferred embodiment of the drill string according to the invention the cross-section of the cavity along the main axis increases in si ze over at least part of the depth of the cavity .

[0011] By increasing the si ze of the cross-section, a shape of the cavity is formed, which allows for a form- fit connection .

[0012] A preferred shape of the cavity is wherein the cavity comprises a truncated cone shaped space along the main axis . The truncated cone shape allows to withstand relative high forces compared to other shapes . This will increase the li fetime of the embedded RFID tag in the drill tube .

[0013] Another shape of the cavity is wherein the cavity comprises a groove arranged in the cavity wall . A groove can easily be machined in a pocket hole and provides for a cost ef fective solution .

[0014] In yet another embodiment of the drill string according to the invention the male connection and female connection of each drill pipe is threaded .

[0015] The RFID tag being embedded in a solidi fied fluid, such as a synthetic resin, filling a cavity, wherein the cavity and resin have a form- fit connection can also be used for other parts used during sonic drilling, such as in the drill bit .

[0016] The invention also relates to a combination of a sonic drill rig having a base and a sonic drill head guided along a vertical guide arranged to the base , and a drill string according to the invention, wherein a RFID scanner is arranged to the vertical guide near the base to detect the RFID tag of each drill pipe passing the RFID scanner .

[0017] The RFID scanner allows to detect which drill pipe is added to the drill string and pushed into the ground . With the characteristics of each speci fic drill pipe , it is possible to calculate the drilling depth .

[0018] A preferred embodiment of the combination according to the invention further comprises a controller for controlling the sonic drill head and the movement thereof along the vertical guide , which controller is connected to the RFID scanner to obtain the length of the drill pipes detected by the RFID scanner in and to determine the drill depth based on the combined length of the drill pipes and the position of the sonic drill head along the vertical guide .

[0019] These and other features of the invention will be elucidated in conj unction with the accompanying drawings .

[0020] Figure 1 shows a schematic view of an embodiment of a combination according to the invention .

[0021] Figure 2 shows a perspective view of an end of a drill pipe for a drill string according to the invention .

[0022] Figure 3 shows a cross-section of figure 2 .

[0023] Figure 4 shows a cross-section of a second embodiment of a drill pipe for a drill string according to the invention .

[0024] Figure 1 shows a schematic view of an embodiment of a combination 1 according to the invention . The combination 1 has a sonic drill rig with a base 2 arranged on tracks 3 to move the sonic drill rig over the ground G . A vertical guide 4 is arranged to the base 2 . A sonic drill head 5 is guided along this vertical guide 4 to push a drill string 6 , 7 , 8 , 9 into the ground G .

[0025] The drill string 6 , 7 , 8 , 9 is composed out of drill pipes 6 , 7 , 8 each having a length li, 12, 12respectively and a drill bit 9 .

[0026] A RFID scanner 10 is mounted to the vertical guide 4 near the base 2 of the sonic drill rig . This RFID scanner 10 scans the RFID tags mounted in the drill pipes 6 , 7 , 8 and drill bit 9 . Together with the position x of the sonic drill head 5 and the respective lengths 12, 12, 12the drill depth d can be calculated .

[0027] The drill depth d can for example be used for an automatic billing system, which sends invoices to customers based on the depth d of the drilled hole .

[0028] The identi fication of the drill pipes 6 , 7 , 8 and drill bit 9 by their respective RFID tags allows for tracking of the several parts and registering the conditions under which the parts were used, such that the parts 6 , 7 , 8 , 9 can timely be serviced .

[0029] Figure 2 shows a perspective view of an end of a drill pipe 20 for a drill string according to the invention . The end of the drill pipe 20 is provided with a threaded male connection to form a j oint with a threaded female connection of another drill pipe .

[0030] An RFID tag 22 is embedded in the outer circumferential surface 23 of the drill pipe 20 . Figure 3 shows a cross-section of figure 2. The RFID tag 22 is positioned on the bottom 24 of a cavity, which is filled with a solidified fluid 25, such as a synthetic resin. The cavity has a main axis 26.

[0031] The cross-section of the cavity along the main axis 26 increases in size over at least part of the depth of the cavity, such that a truncated cone shaped space portion 27 is formed. This provides a form-fit connection of the solidified fluid 25 in which the RFID tag 22 is embedded with the cavity 24, 27. Even if the solidified fluid 25 would detach from the wall of the cavity 24, 27, the truncated cone shape 27 will ensure that the solidified fluid 25 with the RFID tag 22 is kept inside of the cavity 24, 27 due to the form-fit connection .

[0032] Figure 4 shows a cross-section of a second embodiment of a drill pipe 30 for a drill string according to the invention. A cylindrical pocket with bottom 31 and cylindrical wall 32 is arranged into the body 33 of the drill pipe 30. A groove 34 is furthermore provided in the cylindrical wall 32.

[0033] An RFID tag 35 is positioned on the bottom 31 of the cavity 31, 32, 34 and is filled with a solidified liquid 36. Due to the groove 34 a form-fit connection is obtained between the cavity 31, 32, 34 and the solidified liquid 36 in which the RFID tag 35 is embedded.

Claims

6Claims1 . Drill string for a sonic drill rig, which drill string comprises a number of drill pipes , each drill pipe having on one end a male connection and on the other end a female connection, wherein the male connection and female connection of two adj acent drill pipes form a j oint to connect the respective drill pipes together and to form a string, wherein each drill pipe is provided with an RFID tag containing a code unique to the drill pipe , wherein the RFID tag is arranged in a cavity provided in the drill pipe , characterized in that the RFID tag of each drill pipe is embedded in a solidi fied fluid, such as a synthetic resin, filling the cavity and wherein the cavity and resin have a form- fit connection .2 . Drill string according to claim 1 , wherein the cavity of each drill pipe is arranged in the outer circumferential surface of the drill pipe and wherein the cavity extends from the circumferential surface into the body of the drill pipe along a main axis .3 . Drill string according to claim 2 , wherein the cross-section of the cavity along the main axis increases in si ze over at least part of the depth of the cavity .4 . Drill string according to claim 3 , wherein the cavity comprises a truncated cone shaped space along the main axis .5 . Drill string according to claim 3 , wherein the cavity comprises a groove arranged in the cavity wall .6 . Drill string according to any of the preceding claims , wherein the male connection and female connection of each drill pipe is threaded .7 . Combination of a sonic drill rig having a baseand a sonic drill head guided along a vertical guide arranged to the base , and a drill string according to any of the preceding claims , wherein a RFID scanner is arranged to the vertical guide near the base to detect the RFID tag of each drill pipe passing the RFID scanner .8 . Combination according to claim 7 , further comprising a controller for controlling the sonic drill head and the movement thereof along the vertical guide , which controller is connected to the RFID scanner to obtain the length of the drill pipes detected by the RFID scanner in and to determine the drill depth based on the combined length of the drill pipes and the position of the sonic drill head along the vertical guide .

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