2 ms·

What do these bits look like? How wide are they? How does the drilling work, are they hollow and the material goes in the middle, which you then pull up every

What do these bits look like? How wide are they? How does the drilling work, are they hollow and the material goes in the middle, which you then pull up every now and then? Do they come in sections (how long) and you just keep putting in more? Sorry for many questions just can't find much info on actual field truth (just generic info on theory of operation).

gtvwill 4y ago
So we drilled core for gold. There are two main types of drilling RC and diamond core. RC is like a pneumatic hammer system i didnt work with those so cant say much about them (they recover a dust pile as their sample type, diamond core pulls out preferably a long cylinder core sample that has orientation marked on it (e.g. north). Diamond core drilling tho is basically a cylinder shaped drill bit attached to a hardened drill rod that is attached to a rod string (groups of 3m pipes). Everything is basically done in 3m lengths, mostly for transport reasons. When your drilling you work with the rods in bundles of 3 so 9m lengths. I worked mostly on UDR 1200's and a prototype surface rig that there were like...3 built? partnership between a few big companies. That rig was the one that could do (estimated) up to 3000m or so. Deepest I worked on was 2200m. Drill bit sizes if your interested in looking them up that we worked with are BQ,NQ,HQ,PQ. So external diameters ranging from 60mm with bq (core size of 36.5mm) to PQ @ 122mm ext. and 85 ID. We worked all manual by hand so PQ with a drill barrel weighing like 50kg was our limit. Shaking core from 3m HQ drill rods nearly broke me the first time I did it. The drill barrels have a inner tube that is the core holder/lifter that hangs like a few mm from the spinning bit at all times while drilling, these are 6m long. After you have drilled 3m, you clamp the rod string so its hanging from the drill rig and add 3m until you have preferably 6m drilled. Drilling stops, you pull back on a wireline that is holding the core tube to engage the internal clamps on it and haul up your 6m of core. A empty tube gets sent back down, you add another 3m rod to the string and repeat the process. While this happens the full core tube is orientation marked, shaken out and cleaned and re-assembled as it comes out of the hole in core trays. ^^^^ Everything above is if things go to plan. Rough ground, broken bits, hard ground, loss of water return all kinds of things can cause problems and make runs stop, go short, loose rods, drop core, require bit changes, cause equipment to overload and break so on. Been a few years since I did it but I do kind of miss the work. https://www.youtube.com/watch?v=DUMftmjpdNg https://www.youtube.com/watch?v=DUMftmjpdNg This is a video of after a bit change. they are pushing rods back down the hole to hit the point where drilling stopped. They are moving real slow. 111 rods roughly to 1000m. Worst shift I had was 16 ton of rods moved. >1000m down, started shift pulling rods for a bit change, bit snapped a tooth after we got it back down in under 5m of cutting and had to come straight back out. Hell of a night. If your lucky you have 3 to a rig (driller and two offsiders) if your unlucky its just 2 on a rig. No breaks. You eat while you drill. https://www.youtube.com/watch?v=VF3_TqN6AQA https://www.youtube.com/watch?v=VF3_TqN6AQA This video also covers the whole basics pretty well.
- tomcam 4y ago
  Your comments are opening up a new world for me. Thank you.
- mcnugget 4y ago
  Dam, didn't think I'd see another mining person on hackernews. Exploration geology that far down is wild. Was it core sampling all the way from grade or only in mineralized zones?
  - gtvwill 4y ago
    Core sampling the whole way. Outskirts of jundee at wiluna. Punched a few holes down the side of the pit while I was there and the deep holes were for underground to work out where they were going. Most target zones 800-1200. I got lucky as the drillers I offsided with were absolute guns so we got the hard stuff. Best day we cracked >100m in our 12 hours and cross shift got 80m. 22mins was out fastest 6m off memory. That was shallow work tho, deep holes can take 45m just to pull a core tube. I don't drill any more but do kind of miss the work.
    - grecy 4y ago
      Huh, I just drove the canning, I was in wiluna two weeks ago!
jcampbell1 4y ago
The drilling fluid/mud is pumped down the center of the string and flows back up the sides of the bore hole. The material removed comes up with the drilling fluid. The drill string is a chain of threaded pipes. There is tons of good information online, just search for oil well drilling on YouTube.
- gtvwill 4y ago
  Geez https://amcmud.com/drilling-fluids/ https://amcmud.com/drilling-fluids/ if you want to look into some of the fluids/chems used in drilling. This stuff is nuts, https://amcmud.com/product/amc-cr-650/ https://amcmud.com/product/amc-cr-650/ Have sent pallets of the stuff down hole. Few 500ml scoops of that and you can turn 5000l of water into some crazy thick mud for bringing up heavy cuttings. Worst experience tho copping a face full of dust when dosing it tho, gets in your eyes. Takes a ridiculous amount of water to wash past the thickening point and get it out.
  - jcampbell1 4y ago
    I once had the task of measuring powdered dye for industrial soap. A coworker told me to make sure and tamp down the can. Turns out tamping the can kicks up just enough dust that I had blue snot for a week. Not an OSHA approved practical joke, but funny nonetheless.

gtvwill 4y ago

So we drilled core for gold. There are two main types of drilling RC and diamond core. RC is like a pneumatic hammer system i didnt work with those so cant say much about them (they recover a dust pile as their sample type, diamond core pulls out preferably a long cylinder core sample that has orientation marked on it (e.g. north). Diamond core drilling tho is basically a cylinder shaped drill bit attached to a hardened drill rod that is attached to a rod string (groups of 3m pipes). Everything is basically done in 3m lengths, mostly for transport reasons. When your drilling you work with the rods in bundles of 3 so 9m lengths. I worked mostly on UDR 1200's and a prototype surface rig that there were like...3 built? partnership between a few big companies. That rig was the one that could do (estimated) up to 3000m or so. Deepest I worked on was 2200m. Drill bit sizes if your interested in looking them up that we worked with are BQ,NQ,HQ,PQ. So external diameters ranging from 60mm with bq (core size of 36.5mm) to PQ @ 122mm ext. and 85 ID. We worked all manual by hand so PQ with a drill barrel weighing like 50kg was our limit. Shaking core from 3m HQ drill rods nearly broke me the first time I did it. The drill barrels have a inner tube that is the core holder/lifter that hangs like a few mm from the spinning bit at all times while drilling, these are 6m long. After you have drilled 3m, you clamp the rod string so its hanging from the drill rig and add 3m until you have preferably 6m drilled. Drilling stops, you pull back on a wireline that is holding the core tube to engage the internal clamps on it and haul up your 6m of core. A empty tube gets sent back down, you add another 3m rod to the string and repeat the process. While this happens the full core tube is orientation marked, shaken out and cleaned and re-assembled as it comes out of the hole in core trays. ^^^^ Everything above is if things go to plan. Rough ground, broken bits, hard ground, loss of water return all kinds of things can cause problems and make runs stop, go short, loose rods, drop core, require bit changes, cause equipment to overload and break so on. Been a few years since I did it but I do kind of miss the work. https://www.youtube.com/watch?v=DUMftmjpdNg https://www.youtube.com/watch?v=DUMftmjpdNg This is a video of after a bit change. they are pushing rods back down the hole to hit the point where drilling stopped. They are moving real slow. 111 rods roughly to 1000m. Worst shift I had was 16 ton of rods moved. >1000m down, started shift pulling rods for a bit change, bit snapped a tooth after we got it back down in under 5m of cutting and had to come straight back out. Hell of a night. If your lucky you have 3 to a rig (driller and two offsiders) if your unlucky its just 2 on a rig. No breaks. You eat while you drill. https://www.youtube.com/watch?v=VF3_TqN6AQA https://www.youtube.com/watch?v=VF3_TqN6AQA This video also covers the whole basics pretty well.

tomcam 4y ago
Your comments are opening up a new world for me. Thank you.
mcnugget 4y ago
Dam, didn't think I'd see another mining person on hackernews. Exploration geology that far down is wild. Was it core sampling all the way from grade or only in mineralized zones?
- gtvwill 4y ago
  Core sampling the whole way. Outskirts of jundee at wiluna. Punched a few holes down the side of the pit while I was there and the deep holes were for underground to work out where they were going. Most target zones 800-1200. I got lucky as the drillers I offsided with were absolute guns so we got the hard stuff. Best day we cracked >100m in our 12 hours and cross shift got 80m. 22mins was out fastest 6m off memory. That was shallow work tho, deep holes can take 45m just to pull a core tube. I don't drill any more but do kind of miss the work.
  - grecy 4y ago
    Huh, I just drove the canning, I was in wiluna two weeks ago!

jcampbell1 4y ago

The drilling fluid/mud is pumped down the center of the string and flows back up the sides of the bore hole. The material removed comes up with the drilling fluid. The drill string is a chain of threaded pipes. There is tons of good information online, just search for oil well drilling on YouTube.

gtvwill 4y ago
Geez https://amcmud.com/drilling-fluids/ https://amcmud.com/drilling-fluids/ if you want to look into some of the fluids/chems used in drilling. This stuff is nuts, https://amcmud.com/product/amc-cr-650/ https://amcmud.com/product/amc-cr-650/ Have sent pallets of the stuff down hole. Few 500ml scoops of that and you can turn 5000l of water into some crazy thick mud for bringing up heavy cuttings. Worst experience tho copping a face full of dust when dosing it tho, gets in your eyes. Takes a ridiculous amount of water to wash past the thickening point and get it out.
- jcampbell1 4y ago
  I once had the task of measuring powdered dye for industrial soap. A coworker told me to make sure and tamp down the can. Turns out tamping the can kicks up just enough dust that I had blue snot for a week. Not an OSHA approved practical joke, but funny nonetheless.