Research Article

Dynamic Characteristics and Key Parameter Optimization of Mechanical Automatic Vertical Drilling Tools

Table 1

The theoretical values of platform design parameters.

Parameter nameParameter value

Outer diameter (m)0.11
Inner diameter (m)0.045
Density (kg/m3)11000
Gravity acceleration (m/s2)9.8
Friction radius of thrust bearing (m)0.08375
Friction coefficient of thrust bearing 0.0015
Friction radius of radial bearing (m)0.081
Friction coefficient of radial bearing (m)0.0025
Fluid pressure on disc valve (MPa)1
Pressure area of disc valve (mm2)2713
Friction radius of disc valve (m)0.054
Friction coefficient of disc valve 0.2