As a novel guidance equipment for directional drilling, ORT wireless transmission magnetic guidance system is independently developed by Orient for HDD equipment, which is also an advanced equipment popular at home and abroad with independent intellectual property right and independently innovation. A new wireless electromagnetic communication technology is applied for communication part, and the guidance part still applies mature magnetic guidance technology of the Orient. Furthermore, the positioning function of artificial magnetic field is added in the system.
The ORT wireless transmission magnetic guidance system is a new type of guidance equipment for crossing projects with the characteristics of deep and long distance in order to achieve the expectation that an important role will be played in the guidance drilling field.
1. Fundamental Principle:
The guidance instrument installed in drilling tool acquires and processes the date such as pitch angle, magnetic azimuth angle, tool face angle and ground artificial magnetic field that will be sent to the drive sub for coding and output of those data based on the configured coding program. The signal is fed to both ends of the antenna insulator via a drive circuit, and then transmitted to the ground in the form of radio electromagnetic wave through the guidance of drill pipe. The ground receiving antenna receives the signal and sends to the processing instrument for amplification, detection, digital processing, demodulation, error correction and recovery. Then the recovered signal will be sent to computer for the calculation of well trajectory and sketch drafting as well as direction control of the downhole motor.
2.Main Functions and Features:
a.The wireless transmission magnetic guidance system is suitable for large horizontal directional drilling machine, which is used for long distance, large depth and complicated crossing guidance in construction conditions.
b.Instead of wire magnetic guidance instrument, it solve the inconvenience of the construction caused by cable guidance instrument will be solved, such as wiring of each drill pipe, leakage caused by poor sealing of wire and wire damage etc.
c.In the process of drilling, the function of automatic tracking on drilling trajectory length will accelerate the construction progress and reduce the cost of manpower and material without wiring.
d.The unique designed positioning function for artificial magnetic field is able to assist the magnetic guidance instrument to make the exit point and drilling trajectory more accurate and reliable, ensuring that the drilling trajectory is highly consistent with the designed trajectory.
3.Technical Features:
a.Strong applicability: Simple and reliable system, easy operation for HMI in Chinese language. Easy arrangement of artificial magnetic field and small influence affected from complicated formations compared with the wired guidance instrument.
b.High efficiency: Wireless transmission of system data in the form of electromagnetic wave. Time saving and high construction efficiency compared with wired guidance instrument during the construction.
c.Automatic tracking on length: Automatic tracking on the footage of the drill hole and more accurate data acquisition on the location of drill pipe.
d.Completeness of terminal data output: HMI in Chinese language, real-time measurement and acquisition on data of motor and length, real-time calculation, and real-time output of documents containing 2D profile and plan as well as data sheet of the trajectory for drill hole.
4.Highlights on System Technology:
In order to meet the requirement of guiding equipment in directional drilling projects of long distance and large depth and improve the nationalization level of guidance equipment, the wireless magnetic communication system for horizontal directional drilling is independently developed to enhance data processing function for the magnetic guidance instrument. Meanwhile, the positioning system of artificial magnetic field for horizontal directional drilling is also developed independently. Those two systems are advanced and popular at home and abroad with independent intellectual property right and independently innovation, and are the technical core and highlights for ORT wireless transmission magnetic guidance system.
