Raro te poka dth sd mission 6” hama me te utu moka
Ko te awhe tino pai o te rahi o te rua mo te keri poka pupuhi me te DTH he 90 mm ki te 254 mm (3 ½”–10″).Ko nga kohao pupuhi iti ka keria ma te whakamahi i te tophammer, ka whakamahia nga kohao nui ki nga miihini hurihuri.I etahi atu tono, penei i te keri turanga, ka taea te whakamahi i nga hama DTH me te moka kotahi ki te rahi o te kohao tae atu ki te .750 mm (30″).Me te maha o nga waahanga hama CD (Cluster drills) nga rua wiri ki te 70″, 1778 mm ranei.
Ka rite ki te tikanga o te koromatua, ko te iti rawa te diameter o te kohao ka taea e te hama DTH te keri ko tona rahinga ingoa.Ma te hama 4 inihi ka keri he poka 4 inihi (102 mm).Ko te mea whakaiti ko te diameter o waho o te hama, na te mea, i te mea ka heke te diameter o te kohao, ka aukati te rere o te hau.Ko te rahinga nui o te kohao mo te mahi keri ko te rahi o te hama me te 1 inihi, no reira mo te hama 4 inihi te rahi o te kohao ko te 5 inihi (127–130 mm).
Ko te whiriwhiri i te hama tika ka whakatauhia ma te rahi o te rua me te momo toka.Ko te mea pai, kia rite te rahi o te hama ki te inenga o te kohao e hiahiatia ana kia rite ki te mea e taea ana, me waiho noa he waahi mo nga haea hei wehe i te poka.
| Tauira | Hononga Miro | OD(mm) | Te Rahi Puka | Kāhua Shank | Pēhanga Mahi(Pae) |
| CD35 | API 2 3/8" Reg | φ82mm | φ90-φ105 | DHD3.5 CD35 | 1.0-1.5Mpa |
| CD45 | API 2 3/8" Reg | φ99mm | φ110-φ135 | Cop44 DHD340 CD45 | 1.0-2.5Mpa |
| CSD4 | API 2 3/8" Reg | φ99mm | φ110-φ135 | SD4 CSD4 | 1.0-2.5Mpa |
| CQL40 | API 2 3/8" Reg | φ99mm | φ110-φ135 | QL40 CQL40 | 1.0-2.5Mpa |
| CD55 | API 2 3/8" Reg API 3 1/2" Reg | φ125mm | φ135-φ155 | Cop54 DHD350R CD55 | 1.0-2.5Mpa |
| CSD5 | API 3 1/2" Reg | φ125mm | φ135-φ155 | SD5 CSD5 | 1.0-2.5Mpa |
| CQL50 | API 3 1/2" Reg | φ125mm | φ135-φ155 | Cop54 QL50 CQL50 | 1.0-2.5Mpa |
| CD65 | API 3 1/2" Reg | φ148mm | φ155-φ190 | Cop64 DHD360 CD65 | 1.0-2.5Mpa |
| CSD6 | API 3 1/2" Reg | φ148mm | φ155-φ190 | SD6 CSD6 | 1.0-2.5Mpa |
| CQL60 | API 3 1/2" Reg | φ148mm | φ155-φ190 | Cop64 QL60 CQL60 | 1.0-2.5Mpa |
| CD85 | API 4 1/2" Reg | φ185mm | φ195-φ254 | Cop84 DHD380 CD85 | 1.0-2.5Mpa |
| CSD85 | API 4 1/2" Reg | φ185mm | φ195-φ254 | SD8 CSD8 | 1.0-2.5Mpa |
| CQL80 | API 4 1/2" Reg | φ185mm | φ195-φ254 | QL80 CQL80 | 1.0-2.5Mpa |
| CSD10 | API 4 1/2" Reg API 5 1/2" Reg API 6 5/8" Reg | φ225mm | φ254-φ311 | SD10 CSD10 | 1.0-2.5Mpa |
| CN100 | API 6 5/8" Reg | φ225mm | φ254-φ311 | NUMA100 CN100 | 1.0-2.5Mpa |
| CSD12 | API 6 5/8" Reg | φ275mm | φ305-φ445 | SD12 CSD12 | 1.0-2.5Mpa |
