DRILL COLLAR NUMBER OR SIZE TYPE |
MINUMUM OD |
BORE TOL. +1/16 (B) |
LENGTH (FT) TOL.+6" (C) |
BENDING STRENGTH RATIO (2) |
APPROX.WEIGTH OF 31 FT DRILL COLLAR (LB) |
N.C. 26-35 (2 3/8 I.F.)
N.C. 31-41 (2 7/8 I.F.)
N.C. 38-47 (3 1/2 I.F.)
N.C. 38-50 (3 1/2 I.F.)
|
3 1/2
4 1/8
4 3/4
5
|
1 1/2
2
2 1/4
21/4
|
30
30
31
31
|
2.42:1
2.43:1
1.85:1
2.38:1
|
800 (3)
1040 (3)
1450
1650
|
N.C. 44-60
N.C. 44-60
N.C. 44-62
N.C. 46-62(4 I.F.)
|
6
6
6 1/4
6 1/4
|
2 1/4
2 13/16
2 1/4
2 13/16
|
31
31
31 or 32
31 or 32
|
2.49:1
2.84:1
2.91:1
2.63:1
|
2560
2350
2810
2600
|
N.C. 46-65 (4 I.F.)
N.C. 46-65 (4 I.F.)
N.C. 46-67 (4 I.F.)
|
6 1/2
6 1/2
6 3/4
|
2 1/4
2 13/16
2 1/4
|
31 or 32
31 or 32
31 or 32
|
2.76:1
3.05:1
3.18:1
|
3090
2880
3360
|
N.C. 50-70 (4 1/2 I.F.
N.C.50-70 (4 1/2 I.F.)
N.C.50-72 (4 1/2 I.F.)
|
7
7
7 1/4
|
2 1/4
2 13/16
2 13/16
|
31 or 32
31 or 32
31 or 32
|
2.54:1
2.73:1
3.12:1
|
3640
3440
3710
|
6 5/8 REG
6 5/8 REG
|
8
8 1/4
|
2 13/16
2 13/16
|
31 or 32
31 or 32
|
2.60:1
2.93:1
|
4680
5020
|
7 5/8 REG.
7 5/8 REG. (1)
8 5/8 REG. (1)
|
9 1/2
9 3/4
11
|
3
3
3
|
31 or 32
31 or 32
30
|
2.81:1
3.09:1
2.78:1
|
6730
7130
8970 (3)
|