Special Feature
Drill collar features
·high quality, unique selection
·special intermediate frequency heat treatment technique
·satisfies API SPEC7-1 requests
·UT&MT inspection
·strict quality control system
·can produce normal drill collar, spiral drill collar and non-magnetic drill collar.
Drill collar List
|
Nominal size
|
D
|
d
|
Lmm
|
DF(mm)
|
Bending Strength ratio
|
|
mm
|
In
|
mm
|
in
|
|
NC31-41(2-7/8IF)
|
104.8
|
4-1/8
|
50.8
|
2
|
9150
|
100.4
|
2.43:1
|
|
NC35-47
|
120.7
|
4-3/4
|
50.8
|
2
|
9150
|
114.7
|
2.58:1
|
|
NC38-50(3-1/2IF)
|
127.0
|
5
|
57.2
|
2-1/4
|
9150
|
121.0
|
2.38:1
|
|
NC44-60
|
152.4
|
6
|
57.2
|
2-1/4
|
9150/9450
|
144.5
|
2.49:1
|
|
NC44-60
|
152.4
|
6
|
71.4
|
2-13/16
|
9150/9450
|
144.5
|
2.84:1
|
|
NC44-62
|
158.8
|
6-1/4
|
57.2
|
2-1/4
|
9150/9450
|
149.2
|
2.91:1
|
|
NC46-62(4IF)
|
158.8
|
6-1/4
|
71.4
|
2-13/16
|
9150/9450
|
150.0
|
2.63:1
|
|
NC46-65(4IF)
|
165.1
|
6-1/2
|
57.2
|
2-1/4
|
9150/9450
|
154.8
|
2.76:1
|
|
NC46-65(4IF)
|
165.1
|
6-1/2
|
71.4
|
2-13/16
|
9150/9450
|
154.8
|
3.05:1
|
|
NC46-67(4IF)
|
171.4
|
6-3/4
|
57.2
|
2-1/4
|
9150/9450
|
159.5
|
3.18:1
|
|
NC50-67(4-1/2IF)
|
171.4
|
6-3/4
|
71.4
|
2-13/16
|
9150/9450
|
159.5
|
2.37:1
|
|
NC50-70(4-1/2IF)
|
177.8
|
7
|
57.2
|
2-1/4
|
9150/9450
|
164.7
|
2.54:1
|
|
NC50-70(4-1/2IF)
|
177.8
|
7
|
71.4
|
2-13/16
|
9150/9450
|
164.7
|
2.73:1
|
|
NC50-72(4-1/2IF)
|
184.2
|
7-1/4
|
71.4
|
2-13/16
|
9150/9450
|
169.5
|
3.12:1
|
|
NC56-77
|
196.8
|
7-3/4
|
71.4
|
2-13/16
|
9150/9450
|
185.3
|
2.70:1
|
|
NC56-80
|
203.2
|
8
|
71.4
|
2-13/16
|
9150/9450
|
190.1
|
3.02:1
|
|
6-5/8REG
|
209.6
|
8-1/4
|
71.4
|
2-13/16
|
9150/9450
|
195.7
|
2.93:1
|
|
NC61-90
|
228.6
|
9
|
71.4
|
2-13/16
|
9150/9450
|
212.7
|
3.17:1
|
|
7-5/8REG
|
241.3
|
9-1/2
|
76.2
|
3
|
9150/9450
|
223.8
|
2.81:1
|
|
NC70-97
|
247.6
|
9-3/4
|
76.2
|
3
|
9150/9450
|
232.6
|
2.57:1
|
|
NC70-100
|
254.0
|
10
|
76.2
|
3
|
9150/9450
|
237.3
|
2.81:1
|
|
