The accurate and real-time measurement of attitude parameters is a prerequisite for the realization of steering control of drilling tools. However, when the guide shaft is in rotation and vibration environment, the output of the inertial sensor measuring the attitude of the guide tool will be affected by the rotational centrifugal acceleration and vibration acceleration, which will distort the measurement signal, increase the Angle measurement error, and lead to the Angle uncertainty.It is very difficult to maintain the long-term use of the inclination probe in the actual working vibration environment of well logging. ERICOO’s high-temperature accelerometers currently are all quartz flexible accelerometers, which have strong anti-interference ability, good dynamic performance and measurement accuracy. High features, while enhancing stability and service life.
Quartz flexible accelerometer is a single-axis gravity accelerometer, which is characterized by simple structure, small volume, high precision and sensitivity, and high reliability.
The working principle of the quartz flexible accelerometer is that when the inertial mass is subjected to external acceleration, the relative position is slightly shifted, causing the change of the distance between the differential capacitor plates and the change of the differential capacitance. The servo amplifier detects this change and outputs the corresponding current, which is sent to the coil located inside the magnetic field to generate a feedback torque that is balanced with the input acceleration torque, and the inertial mass returns to the equilibrium position again. By measuring this current signal, the input acceleration can be calculated.
The quartz flexible accelerometer consists of a meter head and a servo circuit. The quartz flexible accelerometer used in the inclinometer probe is innovatively optimized for the meter head and the servo circuit.
The meter head includes proof mass assembly, upper torquer assembly and upper torquer assembly. Among them, the main problem that affects the high temperature working life is the connection between the terminal and the gold-plated film of the quartz pendulum. Generally, the method adopted by the manufacturer is to connect by soldering. Because of the problem of tin corrosion of the gold film, the high temperature working life and anti-vibration ability will be affected. Influence. The difference from ordinary quartz watch heads is that gold wire bonding is used to connect the IC chip to the package pins to enhance reliability and life.
The servo circuit consists of a differential capacitance detector, an integrator, and a compensation amplifier. ERICCO’s high-temperature quartz accelerometer ER-QA-03D improves the performance for long-term reliability in a 175° high temperature working environment. Compared with ordinary plastic packaging process chips, the multi-chip module thick-film hybrid integrated circuit process is used to solve the problem of not being able to work for a long time in a high temperature environment of 175°. In addition, the accelerometer uses a temperature sensor, which the operator can use to compensate Bias and Scale factor parameters to reduce the influence of temperature factors.
Accelerometer sensors are mainly used in drilling inclinometer system and continuous inclinometer system of oil drilling to measure the slope of drilling. When observing with a clinometer, the probe moves from the bottom of the clinometer tube to the top, pauses and measures the tilt at a distance of half a meter. The tilt of the probe is measured by two balanced servo accelerometers. An accelerometer measures the longitudinal position of the groove of the inclinometer tube, that is, the inclination of the plane on which the inclinometer probe is located. The other accelerometer measures the inclination perpendicular to the plane of the wheel. The inclination can be converted into lateral displacement. Comparing the current and initial observational data, it is possible to determine the amount of lateral migration change and show the movement displacement occurring in the formation. Plotting the change in the offset gives a high resolution displacement profile. This profile helps determine the magnitude, depth, direction, and rate of ground motion displacement.
