Mtengo wa API trione kubowola IADC216 4 5/8 mainchesi (118mm)

4 5/8" TCI tricone bit imagwiritsidwa ntchito kwambiri pobowola madzi, kufufuza, dzenje loyendetsa ndege la HDD, kuyika maziko, ili ndi mapangidwe apakati a jet hole, kotero imagwiranso ntchito pobowola mozungulira mozungulira.
Chovalacho chimasindikizidwa, moyo wogwira ntchito ndi wautali kwambiri kuposa zingwe zotseguka zonyamula.
Mano achitsulo amtundu wa tricone bit ali ndi dzenje lapakati lomwe ndiloyenera kubowola RC (Reverse Circulation kubowola).
IADC216 tricone bit imatha kubowola zolimba kuposa IADC126, kusankha IADC yoyenera molingana ndi kuuma kwa miyala ndiye gawo loyamba la kubowola koyenera kwambiri. Far Eastern Drilling ndi fakitale yovomerezeka ya API ya trione roller bit.