Feedback of piling core barrel

There is no mud pump in rotary piling rig, so it is no mud circulation during drilling of rock core barrel, big chipes can not be circulated to ground, so rock chips are rolling at hole bottom again and again from big to small which wear the body of cones too much. So you could see 1200+ meters footage in traditional vertical well drilling for only 1 piece of tricone bit, and you could see 1000+ meters length in horizontal directional drilling, but you could only see 70+ meters in foundation hard rock piling.

Here is the video of recording Solidkey roller cone bits on piling core barrel. 

It is 800mm piling core barrel, using 6 pieces of SolidKey roller cone bits, model No. NG2(49/7.7). 

Rotary drill rig is Sany 360, drilling site is at Shenzhen City, Guangdong Province, China, rock hardness is more than 120MPa.

We could see the conditions of creo barrel, after drilled 10 meters, after drilled 30 meters, and it still could drill more hard rocks after drilled 48 meters. The customers are always satisfied, because the total footage is always around 70 meters in drilling rocks hardness more than 120MPa.