EN 
- Technical Features
- Technical Parameters
Main Technical Features
● Material: 4145H/4145Hmod or Non-magnetic.
●.Standard: API SPEC 7-1, NS-1.
● Types: Slick Drill Collars, Spiral Drill Collars, Non-magnetic Drill Collars
●Thread Protectors: Steel, cast steel and plastic steel thread protectors for drill collars
A Slick Drill Collar
Drill collar is mainly used to provide bit weight to drill bit so that drill pipe is in tension.
Especially drill collar can keep drill bit centralized and hole track by large rigidity. The Drill collar
are manufactured strictly from API Spec7-1 and NS-1 standard.
B Spiral Drill Collar
Spiral drill collar is used to reduce contact area with hole so as to avoid efficiently bit sticking
from differential pressure. The drill collars are manufactured strictly according to API Spec7-1.
C. Elevator Groove And Slip Groove
Elevator groove and slip groove made on box thread face of slick drill collar or spiral drill collar
can be used as lifting sub and safety slip when trip out. The technical parameters for elevator
groove and slip groove is as per API SPEC7-1. Hard banding is optional at customers’ requests.
D. Non-magnetic Drill Collar
Cold roiled finish on both ID and OD surface with unique technical process strengthen the
structure and ensures the tools with optimal resistance to stress, corrosion, cracking and the
mechanical performance is greatly enhanced.
| Drill Collar Thread | OD | ID | Length | ||
|---|---|---|---|---|---|
| mm | in | mm | in | mm | |
| NC31-41（27/8IF | 104.8 | 4 1/8 | 50.8 | 2 | 9150 |
| NC35-47 | 120.7 | 4 3/4 | 50.8 | 2 | 9150 |
| NC38-50（31/2IF） | 127 | 5 | 57.2 | 2 1/4 | 9150 |
| NC44-60 | 152.4 | 6 | 57.2 | 2 1/4 | 9150or9450 |
| NC44-60 | 152.4 | 6 | 71.4 | 2 13/16 | 9150or9450 |
| NC44-62 | 158.8 | 6 1/4 | 57.2 | 2 1/4 | 9150or9450 |
| NC46-62（4IF） | 158.8 | 6 1/4 | 71.4 | 2 13/16 | 9150or9450 |
| NC46-65（4IF | 165.1 | 6 1/2 | 57.2 | 2 1/4 | 9150or9450 |
| NC46-65（4IF | 165.1 | 6 1/2 | 71.4 | 2 13/16 | 9150or9450 |
| NC46-67（4IF） | 171.4 | 6 3/4 | 57.2 | 2 1/4 | 9150or9450 |
| NC50-67（41/2IF） | 171.4 | 6 3/4 | 71.4 | 2 13/16 | 9150or9450 |
| NC50-70（41/2IF） | 177.8 | 7 | 57.2 | 2 1/4 | 9150or9450 |
| NC50-70（41/2IF） | 177.8 | 7 | 71.4 | 2 13/16 | 9150or9450 |
| NC50-72（41/2IF） | 184.2 | 7 1/4 | 71.4 | 2 13/16 | 9150or9450 |
| NC56-77 | 196.8 | 7 1/4 | 71.4 | 2 13/16 | 9150or9450 |
| NC56-80 | 203.2 | 8 | 71.4 | 2 13/16 | 9150or9450 |
| 65/xREG | 209.6 | 8 1/4 | 71.4 | 2 13/16 | 9150or9450 |
| NC61-90 | 228.6 | 9 | 71.4 | 2 13/16 | 9150or9450 |