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GJ/GJT rock bits
metaL SEALED BIT WITH ROLLER BEATING
GJ/GJT series rock bit adopts metal seal with roller bearing ,which can drill stably with middle to low WOB and middle to high RPM,it is the ideal choice for higher part of well section.
The size range of GJ/GJT series rock bit is from8 1/2 to 17 1/2 inch, and IADC varies from 115 to 545.For example:17 1/2 GJT515GC rock bits
MAIN STRUCTURE FEATURES
- sizes of bearing journal and rollers are made larger by arranging the rollers in recesses in cone body.
- All rubber compensator is used which can limit pressure differential and prevent drilling fluid from entering the lubrication system and this provides the bearing system with good assurance of lubrication.
- Shirttail and head OD are hardfaced for enhanced gage protection. Center nozzle is equipped for bits of larger sizes.
- For GJT,a row of inserts is added between gage row and heel row to trim borehole wall and protect cone shell.
Bit type | HJ117 |
Applicable formation | Very soft with low compressive strength and high drillabilty,such as soft shale ,clay and salt bed,etc. |
Main characteristics of the bit &Cutting Stracture | Hardfaced gage and all tooth surface and the gage fitted with compacts for enhanced gage protections |
Normal WOB Kn/mm(bit dia) | 0.30~0.90 |
Rotary Speed（rpm） | 300~80 |
Bit type | HJ127 |
Applicable formation | Very soft with low compressive strength and high drillabilty,such as soft shale ,clay and salt bed,etc. |
Main characteristics of the bit &Cutting Stracture | Hardfaced gage and all tooth surface and the gage fitted with compacts for enhanced gage protections |
Normal WOB Kn/mm(bit dia) | 0.30~0.90 |
Rotary Speed（rpm） | 300~80 |
Bit type | HJ137 |
Applicable formation | Soft to medium soft with low compressive strength or soft with harder stringers,such as hard gypsolyte,soft timestone and limestone, etc. |
Main characteristics of the bit &Cutting Stracture | Hardfaced gage and all tooth surface and the gage fitted with compacts for enhanced gage protections |
Normal WOB Kn/mm(bit dia) | 0.3~0.90 |
Rotary Speed（rpm） | 300~80 |
Bit type | HJ417 |
Applicable formation | Long section of soft information with low compressive strength and high drillabilty,such as soft shale ,clay and salt bed and soft limestone ,etc. |
Main characteristics of the bit &Cutting Stracture | Large radius,offset crested scoop compacts in inner roe wedge compacts in outer row ,high compact exposure and inequable spaced compacts arrangement. |
Normal WOB Kn/mm(bit dia) | 0.35~0.90 |
Rotary Speed（rpm） | 280~60 |
Bit type | HJ437 |
Applicable formation | soft with low compressive strength and high drillabilty,such as soft shale ,clay and salt bed gypsolyte,and soft limestone ,etc. |
Main characteristics of the bit &Cutting Stracture | Large radius,offset crested scoop compacts in inner roe wedge compacts in outer row ,high compact exposure and inequable spaced compacts arrangement. |
Normal WOB Kn/mm(bit dia) | 0.35~1.00 |
Rotary Speed（rpm） | 240~60 |
Bit type | HJ447 |
Applicable formation | Soft with low compressive strength or soft with harder stringers,such as hard gypsolyte,soft timestone and limestone, etc |
Main characteristics of the bit &Cutting Stracture | Large radius,offset crested scoop compacts in inner roe wedge compacts in outer row ,high compact exposure and inequable spaced compacts arrangement. |
Normal WOB Kn/mm(bit dia) | 0.35~1.05 |
Rotary Speed（rpm） | 240~60 |
Bit type | HJ517 |
Applicable formation | soft with low compressive strength and high drillabilty,such as soft shale ,clay and salt bed and soft limestone ,etc. |
Main characteristics of the bit &Cutting Stracture | Large radius,offset crested scoop compacts in inner roe wedge compacts in outer row ,high compact exposure and inequable spaced compacts arrangement. |
Normal WOB Kn/mm(bit dia) | 0.35~1.05 |
Rotary Speed（rpm） | 240~60 |
Bit type | HJ527 |
Applicable formation | soft with low compressive strength and high drillabilty,such as soft shale ,clay and salt bed and soft limestone ,etc. |
Main characteristics of the bit &Cutting Stracture | Large radius,offset crested scoop compacts in inner roe wedge compacts in outer row ,high compact exposure and inequable spaced compacts arrangement. |
Normal WOB Kn/mm(bit dia) | 0.35~1.00 |
Rotary Speed（rpm） | 240~50 |
Bit type | HJ537 |
Applicable formation | Medium soft with low compressive strength and harder abrasive stringers,,such as soft shale ,clay,sandstone and soft limestone ,dolomite with stringers ,etc |
Main characteristics of the bit &Cutting Stracture | Large radius,offset crested scoop compacts in inner roe wedge compacts in outer row ,high compact exposure and inequable spaced compacts arrangement. |
Normal WOB Kn/mm(bit dia) | 0.50~1.05 |
Rotary Speed（rpm） | 220~40 |
Bit type | HJ547 |
Applicable formation | Medium soft with low compressive strength and harder abrasive stringers,,such as hard shale ,clay,mudstone and soft limestone ,and sandstone ,etc |
Main characteristics of the bit &Cutting Stracture | Large rudius offset crested scoop compacts in inner roe wedge compacts in outer row , and inequable spaced compacts arrangement. |
Normal WOB Kn/mm(bit dia) | 0.50~1.05 |
Rotary Speed（rpm） | 220~40 |
Bit type | HJ617 |
Applicable formation | Medium soft with low compressive strength and thick&hard stringers,,such as hard shale ,clay,mudstone and soft limestone ,and mudstone ,sandstone ,etc |
Main characteristics of the bit &Cutting Stracture | Large radius offset crested scoop compacts in inner row wedge compacts in outer row , inequable spaced compacts arrangement. |
Normal WOB Kn/mm(bit dia) | 0.50~1.05 |
Rotary Speed（rpm） | 200~40 |
Bit type | HJ627 |
Applicable formation | Medium soft with low compressive strength and harder abrasive stringers,,such as hard shale ,clay,mudstone and soft limestone ,and sandstone ,etc |
Main characteristics of the bit &Cutting Stracture | Conical compacts in inner row, wedge compacts in outer row |
Normal WOB Kn/mm(bit dia) | 0.5~1.05 |
Rotary Speed（rpm） | 200~40 |
Bit type | HJ637 |
Applicable formation | Medium soft with low compressive strength and harder abrasive stringers,,such as hard shale ,clay,mudstone and soft limestone ,and sandstone ,etc |
Main characteristics of the bit &Cutting Stracture | Conical compacts in inner row, wedge compacts in outer row. |
Normal WOB Kn/mm(bit dia) | 0.50~1.05 |
Rotary Speed（rpm） | 200~40 |
Bit type | HJ737 |
Applicable formation | Hard formation with high abrasiveness such as hard limestone,dolomite,hard sandstone and chert,ect |
Main characteristics of the bit &Cutting Stracture | Large radius conical compacts in inner row,spherical compacts in out row |
Normal WOB Kn/mm(bit dia) | 0.5~1.20 |
Rotary Speed（rpm） | 200~40
web:http://www.tcirockbit.com |
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