NON MAGNETIC DRILL COLLAR / FLEX COLLAR
Non magnetic drilling tools include Non Magntic Drill Collar/Flex Collar, Stabilizer, MWD components etc. The material is high purity austenitic stainless steel. Strict control of chemical composition and special forging process guarantee the excellent mechanical properties of Shenlong's non magnetic drilling tools. Corrosion resistance rerequirements:Shenlong's all non magnetic produsts can pass the corrosion test specified in ASTM A 262 Practice E.
Non Magnetic Properties:
Relative Permeability: Max 1.005
Hot Spot / Field Gradient:MAX ±0.05μT
Specail Treatment on ID: Roller Burnishing.
(After roller burnishing,a compressive layer come into being),
Advantages are as following:
Increase the corrosion resistance properties;
Increase the surface hardness of bore up to HB400;
Increase surface finish of bore to Ra≤3.2 μm
Test and Inspection carried out on each bar during production of NMDC, Stabilizer and MWD parts:
Chemical Composition;
Tensile Test;
Impact Test;
Hardness Test;
Metallographic Test (Grain Size);
Corrosion Test (According to ASTM A 262 Practice E);
Ultrasonic Test over the whole length of the bar (According to ASTM A 388);
Relative maganetic permeability Test;
Hot spot Test
Dimensional Inspection etc.
Specification of non magnetic drill collars
|
Drill collar
number
and
connection
label
|
Outside
diameter
D
in
|
Bore
d
in
+1/16
0
|
Length
L
Ft
+6
0
|
Bevel
diameter
DF
in
±1/64 in
|
Reference
bending strength
ratio
BSR
|
|
NC23-31
|
3 1/8
|
1 1/4
|
30
|
3
|
2.57:1
|
|
NC26-35
|
3 1/2
|
1 1/2
|
30
|
3 17/64
|
2.42:1
|
|
NC31-41
|
4 1/8
|
2
|
30 or 31
|
3 61/64
|
2.43:1
|
|
NC35-47
|
4 3/4
|
2
|
30 or 31
|
4 33/64
|
2.58:1
|
|
NC38-50
|
5
|
2 1/4
|
30 or 31
|
4 49/64
|
2.38:1
|
|
NC44-60
|
6
|
2 1/4
|
30 or 31
|
5 11/16
|
2.49:1
|
|
NC44-60
|
6
|
2 13/16
|
30 or 31
|
5 11/16
|
2.84:1
|
|
NC44-62
|
6 1/4
|
2 1/4
|
30 or 31
|
5 7/8
|
2.91:1
|
|
NC46-62
|
6 1/4
|
2 13/16
|
30 or 31
|
5 29/32
|
2.63:1
|
|
NC46-65
|
6 1/2
|
2 1/4
|
30 or 31
|
6 3/32
|
2.76:1
|
|
NC46-65
|
6 1/2
|
2 13/16
|
30 or 31
|
6 3/32
|
3.05:1
|
|
NC46-67
|
6 3/4
|
2 1/4
|
30 or 31
|
6 9/32
|
3.18:1
|
|
NC50-70
|
7
|
2 1/4
|
30 or 31
|
6 31/64
|
2.54:1
|
|
NC50-70
|
7
|
2 13/16
|
30 or 31
|
6 31/64
|
2.73:1
|
|
NC50-72
|
7 1/4
|
2 13/16
|
30 or 31
|
6 43/64
|
3.12:1
|
|
NC56-77
|
7 3/4
|
2 13/16
|
30 or 31
|
7 19/64
|
2.70:1
|
|
NC56-80
|
8
|
2 13/16
|
30 or 31
|
7 31/64
|
3.02:1
|
|
6 5/8 REG
|
8 1/4
|
2 13/16
|
30 or 31
|
7 45/64
|
2.93:1
|
|
NC61-90
|
9
|
2 13/16
|
30 or 31
|
8 3/8
|
3.17:1
|
|
7 5/8 REG
|
9 1/2
|
3
|
30 or 31
|
8 13/16
|
2.81:1
|
|
NC70-97
|
9 3/4
|
3
|
30 or 31
|
9 5/32
|
2.57:1
|
|
NC70-100
|
10
|
3
|
30 or 31
|
9 11/32
|
2.81:1
|
|
8 5/8 REG
|
11
|
3
|
30 or 31
|
10 1/2
|
2.84:1
|
Mechanical Properties
|
Steel
Grade
|
OD Range
in
|
Yield Strength
Rt
|
Tensile Strength
Rm
|
Elongation
A
(%)
|
Impact Value
Akv
|
Hardness Brinell
(HB)
|
|
Mpa
|
ksi
|
Mpa
|
ksi
|
|
SLW-1
|
3 1/8 through 6 7/8
|
≥758
|
≥110
|
≥827
|
≥120
|
≥25
|
≥150 longitudinal
|
285-360
|
|
7 through 11
|
≥689
|
≥100
|
|
SLW-2
|
3 1/8 through 6 7/8
|
≥827
|
≥120
|
≥896
|
≥130
|
≥25
|
≥150 longitudinal
|
285-360
|
|
7 through 11
|
≥758
|
≥110
|
|
SLW-3
|
3 1/8 through 6 7/8
|
≥965
|
≥140
|
≥1034
|
≥150
|
≥20
|
≥90 longitudinal
|
330-400
|
|
7 through 11
|
≥896
|
≥130
|
|
SLW-4
|
3 1/8 through 6 7/8
|
≥827
|
≥120
|
≥896
|
≥130
|
≥20
|
≥75 longitudinal
|
285-360
|
|
7 through 11
|
≥758
|
≥110
|
|
Rotary & Handling Tools
