Nā ʻāpana wili hohonu IADC127 12 1/4” (311mm)

Hāʻawi kēia ʻano hana ʻoi aku ka maikaʻi i kahi niho ikaika a ʻoi aku ka pale ʻana i ka hopena ma mua o ka wili ʻana no ka mea ua pale ʻia ke ʻano o nā ʻāpana metala i ka wā o ka forging, e hopena ana i nā niho ikaika. ʻO nā kikoʻī o ka Steel tooth Bit.
Hoʻopaʻa koho ke kaʻina hana wela ʻo Far Eastern Drilling i ka ʻili o ka bearing e hōʻoia i ka paʻa o ka hale. Hāʻawi kēia i ka hana bearing lōʻihi a hilinaʻi hoʻi.
Ke nānā mau ʻia nei ke kaʻina hana paʻakikī niho koʻikoʻi a hōʻano hou ʻia e hōʻoia i ka waiho ʻana o ka paʻakikī niho kiʻekiʻe loa.
He kūpono nā wili niho kila no nā ʻano palupalu loa me ka ikaika compressive haʻahaʻa a me ke kiʻekiʻe o ka wili ʻana e like me ka lepo, ka pōhaku lepo, ka chalk, a pēlā aku. He kūpono nō hoʻi lākou no nā strata waena me ka ikaika compressive kiʻekiʻe, e like me ka shale palupalu, anhydrite, ka limestone palupalu waena, ka one palupalu waena. Stratum waena me kahi interlayer paʻakikī.