Drilling complications

hey, friends i have created a thread to discuss drilling complications here.
As we are drilling a vertical well in north east India, we are facing huge complications here. Need suggestions from expert guys here. Pls come in for discussion.

Drilling is very complicated. Discussion complete.

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The basic problems that we learn from our experience us follows.
[li]You have to get all the rock cuttings out of the hole, which is rather difficult when the hole gets deep.
[/li][li]Cutting through rock wears away the drill bit and drill pipe so you have to keep replacing equipment.
[/li][li]A lot of heat builds up when you drill through rock, so a significant amount of bit cooling is required.
[/li][li]Many rocks aren’t very stable, so the hole may try to collapse.
[/li][li]It’s hard to see through rock, so you often don’t know where you’re drilling.
[/li][li]Most sedimentary rocks contain pressurized fluid in the pore spaces between grains, and those fluids want to flow up the borehole and cause a dangerous blowout.
[/li][li]Subterranean minerals often leach toxic or radioactive materials, so the drilling equipment & fluids can become hazardous to handle.
our company AV Drilling is doing drilling and boring services for more than five years,we face these complications while drilling.

very good topic i want know any thing about this topic