oil drill collar used oil and gas

Standard size ,bores and connection for Drill Collar

Style of connection

OD

ID

Length

Bevel

Bending strength Ratio

mm

in

mm

in

mm

diameter mm

NC23-31

79.4

3 1/8

31.8

1 1/4

9150

76.2

2.57:1

NC26-35(23/8IF)

88.9

3 1/2

38.1

1 1/2

9150

82.9

2.42:1

NC31-41(27/8IF)

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

NC3850(31/2IF)

127.0

5

57.2

2 1/4

9150

121.0

2.38:1

NC44-60

152.4

6

57.2

2 1/4

9150or9450

144.5

2.49:1

NC44-62

158.8

6 1/4

57.2

2 1/4

9150or9450

149.2

2.91:1

NC46-62(4IF)

158.8

6 1/4

71.4

2 13/16

9150or9450

150.0

2.63:1

NC46-65(4IF)

165.1

6 1/2

57.2

2 1/4

9150or9450

154.8

2.76:1

NC46-65(4IF)

165.1

6 1/2

71.4

2 13/16

9150or9450

154.8

3.05:1

NC46-67(4IF)

171.4

6 3/4

57.2

2 1/4

9150or9450

159.5

3.18:1

NC50-67(41/2IF)

171.4

6 3/4

71.4

2 13/16

9150or9450

159.5

2.37:1

NC50-70(41/2IF)

177.8

7

57.2

2 1/4

9150or9450

164.7

2.54:1

NC50-70(41/2IF)

177.8

7

71.4

2 13/16

9150or9450

164.7

2.73:1

NC50-72(41/2IF)

184.2

7 1/4

71.4

2 13/16

9150or9450

169.5

3.12:1

NC50-77

196.8

7 3/4

71.4

2 13/16

9150or9450

185.3

2.70:1

NC50-80

203.2

8

71.4

2 13/16

9150or9450

190.1

3.02:1

6 5/8REG

209.6

8 1/4

71.4

2 13/16

9150or9450

195.7

2.93:1

NC61-90

228.6

9

71.4

2 13/16

9150or9450

212.7

3.17:1

7 5/8REG

241.3

9 1/2

76.2

3

9150or9450

223.8

2.81:1

NC70-97

247.6

9 3/4

76.2

3

9150or9450

232.6

2.57:1

NC70-100

254.0

10

76.2

3

9150or9450

237.3

2.81:1

8 5/8REG

279.4

11

76.2

3

9150or9450

266.7

2.84:1

Mechanical Property of Drill Collar

OD

Yield Strength

Tensile Strength

Elongation

Brinell Hardness HB

Charpy

mm

in inch

σ 0.2 Mpa

σ b Mpa

4%

AKVJ

79.4-171.4

3 1/8-6 3/4

≥758

≥965

≥13

285-341

≥54

177.8-279.4

7-11

≥689

≥930

Stress Relief Groove for Thread Connection

Style of Connection

Length between Inner Thread Shoulder and the last Dens

Diameter of Inner Thread

Taper of the Hole nest to inner Thread

Outer Thread Diameter

Length between alternative Inner Thread Shoulder and Stress Relief Groove

±1.59mm

Dcb+0.40,-0

±20.83

DRG+0 -0.79

LRG +0 -3.18

mm

mm/m

mm

mm

NC35

82.6

82.15

166.67

82.15

85.73

NC38(3 1/2IF)

88.9

88.11

166.67

89.3

92.08

NC44

101.6

101.6

166.67

106.36

104.78

NC46(4IF)

101.6

106.76

166.67

109.93

104.78

NC50(4 1/2IF)

101.6

117.48

166.67

120.65

104.78

NC56

114.3

121.84

250

134.14

117.48

NC61

127

132.95

250

149.25

130.18

NC70

139.7

152

250

171.05

142.88

6 5/8REG

114.3

134.14

166.67

137.72

117.48

7 5/8REG

120.7

133.35

250

162.72

123.83

8 5/8REG

123.8

149.25

250

184.94

127

Note: The connection of NC23,26,31 and 2 3/8IF are without stress relief groove mould for their thin wall.