Drill Collars
Drill collars are made in accordance with API Spec 7 with material AISI 41545H, 4145HM or 4145M.
Drill Collar Standard Sizes and Connection Type
| Size
OD in |
Bore
ID in |
Connection
Type
& Size |
Length |
Bending-Strength Ratio |
Weight |
| m |
ft |
kg |
lbs |
| 31/8 |
1 1/4 |
NC23 |
9.14 |
30 |
2.57:1 |
300 |
622 |
| 31/2 |
11/2 |
NC26
2 3/8 IF |
9.14 |
30 |
2.42:1 |
367 |
809 |
| 4 1/8 |
2 |
NC31
2 7/8 IF |
9.14 |
30 |
2.43:1 |
476 |
1030 |
| 4 3/4 |
2 |
NC35 |
9.14 |
30 |
2.58:1 |
681 |
1502 |
| 5 |
2 1/4 |
NC38
3 1/2 IF |
9.14 |
30 |
2.38:1 |
722 |
1592 |
| 6 |
2 1/4 |
NC44 |
9.45 |
31 |
2.49:1 |
1169 |
2578 |
| 6 |
2 13/16 |
NC44 |
9.45 |
31 |
2.84:1 |
1056 |
2328 |
| 6 1/4 |
2 1/4 |
NC44 |
9.45 |
31 |
2.91:1 |
1281 |
2825 |
| 6 1/4 |
2 13/16 |
NC46
4 IF |
9.45 |
31 |
2.63:1 |
1160 |
2558 |
| 6 1/2 |
2 1/4 |
NC46
4 IF |
9.45 |
31 |
2.76:1 |
1383 |
3050 |
| 6 1/2 |
2 13/16 |
NC46
4 IF |
9.45 |
31 |
3.05:1 |
1277 |
2816 |
| 6 3/4 |
2 1/4 |
NC46
4 IF |
9.45 |
31 |
3.18:1 |
1520 |
3352 |
| 7 |
2 1/4 |
NC50
4 1/2 IF |
9.45 |
31 |
2.54:1 |
1647 |
3632 |
| 7 |
2 13/16 |
NC50
4 1/2 IF |
9.45 |
31 |
2.73:1 |
1548 |
3413 |
| 7 1/4 |
2 13/16 |
NC50
4 1/2 IF |
9.45 |
31 |
3.12:1 |
1675 |
3693 |
| 7 3/4 |
2 13/16 |
NC56
6 5/8 REG |
9.45 |
31 |
2.70:1 |
1957 |
4315 |
| 8 |
2 13/16 |
NC56
6 5/8 REG |
9.45 |
31 |
3.02:1 |
2112 |
4657 |
| 8 1/4 |
2 13/16 |
6 5/8 REG |
9.45 |
3l |
2.93:1 |
2252 |
4966 |
| 9 |
2 13/16 |
NC61
7 5/8 REG |
9.45 |
31 |
3.17:1 |
2746 |
6055 |
| 9 1/2 |
3 |
7 5/8 REG |
9.45 |
31 |
2.81:1 |
3041 |
6705 |
| 9 3/4 |
3 |
NC70
7 5/8 REG |
9.45 |
31 |
2.57:1 |
3224 |
7109 |
| 10 |
3 |
NC70
8 5/8 RGE |
9.45 |
31 |
2.81:1 |
3421 |
7543 |
| 11 |
3 |
NC77
8 5/8 RGE |
9.45 |
31 |
2.78:1 |
4210 |
9283 |
|
Standard Drill Collar and Special Spiral Opion
Non-Magnetic Drill Collar |