應用地層參考

軟巖地層：一般指30MPa以下地層，采用517齒

中硬地層：40-80MPa硬度巖石，采用537、617齒

硬巖地層：大于80MPa巖石，采用637齒

SOFT ROCK FORMATION：≤30MPa,  IADC 517

MEDIUM TO MEDIUM HARD FORMTION: 40-80MPa,IADC 537/617

HARD FORMATION:≥80MPa, IADC637

IADC 217

低抗壓強度的軟到中等地層，如中軟頁巖，中軟石灰?guī)r、中軟砂巖和有硬夾層的軟地層

Soft to medium formation with low compressive strength,such as mid-soft shale,mid -soft limestone,mid-soft sandstone and soft formation with hard interbeds

IADC 517

低抗壓強度的軟地層，如泥巖、石膏、鹽巖、軟頁巖、軟石灰?guī)r

soft formation with low compressive strength ,such as mudstone,gypsum,salinastone,soft shale and soft limestone

IADC537

低抗壓強度的軟到中等地層，如中軟頁巖、中軟石灰?guī)r、中軟砂巖和有較硬研磨性夾層的中等地層

Soft to medium formation with low compressive strength,such as mid-soft shale,mid -soft limestone,mid-soft sandstone and medium formation with harder abrasiveness interbeds

IADC637

高抗壓強度的硬地層，如砂巖、石灰?guī)r、白云巖和硬石膏、大理石

Hard formation with high compressive strength,such as sandstone，limestone,dolomite and anhydrite,marble