1.Cutter placement with

3D-software.

2.Simulation analysis

of flow field well bottom.

3.Computer simulation

processing.

4.Reverse detection

technology.

5.Reverse detection

technology.

6.Analog processing

and testing

7.Optimization of the

angle of the cutting teeth

8.Three-dimensional

model Stress Analysis

9.Bottomhole flow

field vector

10.Nozzle velocity

vector distribution

11.Nozzle Flow

Chart

Bit Size

Connection Size

Make-up Torque

O.D. of Connection

I.D. of Connection  

3 3/4”~4 1/2”

2 3/8”REG 

2.40-4.12kN.m

3 1/8” 

1”

4 5/8”~5”

2 7/8”REG

4.10-6.20kN.m

4 1/8”

1 1/4”

5 1/8”~7 3/8”

3 1/2”REG  

6.90-10.23kN.m 

4 3/4”

1 1/2”

7 13/32”~9 3/8”

4 1/2”REG 

16.63-23.71kN.m 

6 3/4”

1 3/4”

9 13/32”~14 1/2” 

6 5/8”REG 

49.56-51.43kN.m 

8”

3”

14 9/16”~18 1/2” 

7 5/8”REG 

64.52-81.35kN.m 

9 3/4”

3”