英语论文网

Abstract—with development of auto bit feeding technology, the autobit feeding technology is one of main development directions of
automatic drilling. The drilling quality can be improved in variousdrilling status, the accident rate in work, the labor intensity, and
drilling costs can be reduced. The system composition and controlprinciple of auto bit feeding are introduced ，also is the auto bitfeeding with variable frequency timing and disc brake, and the digitalmodel of the auto bit feeding system with constant drilling pressure is
are presented. The research and development of the auto bit feedingtechnology provide necessary technical support for drilling expertsystem. At last some related suggestion and prospect are provided.
Keywords-auto bit feeding system; intelligent drilling; Acvariable frequency; drilling rig
I. INTRODUCTION
The technology of automatic bit feed is needed strongly, in
order to improve the drilling quality, reduce the labor intensity
of the driller. The automatic driller is used to control the
drilling pressure and mechanical rotational speed, the scientific
drilling is achieved according to the setting drilling pressure,
and has much advantage that can not compare with the
artificial control drilling to enhance the drilling quality.
Equipping with the automatic driller has become a trend on
drilling [1].
Viewing around most of the automatic bit feed devices in
the world; they all are classified into some methods as flows:
A. Classification by parameters of the control drilling
1) Control and regulation with constant drilling pressure;
2) Control and regulation with constant penetration rate;
3) Control and regulation with constant torque;
4) Control and regulation with the product value of drilling
pressure and rotational speed.
At present, the method of controlling and regulating with
constant drilling pressure is widely used among all above,
while the method of controlling and regulating with constant
penetration rate and the constant torque are rarely used, and the
way of controlling and regulating with the product value of
drilling pressure and rotational speed is mainly used in the
optimization drilling.
B. Classification by different ways of main drive for the
control system
1) Mechanical types;
2) Pneumatic types;
3) Hydraulic operated types；
4) Electrodynamics types;
5) Electromagnetic types;
6) Computer types.
C. Classification by different installation position
1) The ground-automatic feed drilling equipment；
2) Underground automatic feed drilling devices: this kind
of device is installed on the bit and mainly used in the
directional well.
What’s important is that, the technology of automatic bit
feed may enhance the mechanical rotational speed, improve the
drilling quality. Two ways are mainly adopted in the
technology of automatic bit feed. One is realized by using the
disc brake or the belt brake; another is implemented by an
independence AC motor [2].
II. THE THEORY FOR THE AUTO BIT FEEDING TECHNOLOGY
A. control system
According to the principle of the automatic control, the
closed-loop control should be used, if the technology of the
constant drilling pressure automatic bit feed is adopted. The
closed-loop control means that, there is not only successive
effect, but also rever本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。