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Transient electromagnetic (TEM) techniques have been proven to be efficient for nondestructive testing (NDT) operations due to their pulsed eddy-current properties. However, in the field of downhole measurements, harsh environments may significantly influence the NDT performance in downhole casings. In this paper, an empirical mode decomposition (EMD) method based on borehole TEM array signal denoising and baseline wander (BW) correction is proposed to compensate for the bad measurement conditions that affect downhole NDT. Based on the borehole TEM signal model, we investigated the principle of the EMD approach for the borehole TEM response, where the background magnetic noise and temperature drift effects were analyzed by considering the motion measurement and effective permeability. It was found out that although the BW can be effectively removed with the EMD approach, the performance of the signal denoising is closely related to the measurement speed of the downhole NDT sensors. To solve this problem, we proposed an array-based ensemble EMD method to improve the denoising performance of the borehole TEM signals by formulating a three-dimensional borehole TEM data structure, where the generation of the noise-aided data can be more efficient by employing the borehole TEM array. The performance of the proposed method was verified by applying it to a borehole TEM system for the NDTs of oil-well casings. In addition, field experiments were conducted, and the results demonstrated the effectiveness of the proposed method.

Borehole transient electromagnetic (TEM) array has proven to be efficient for the downhole nondestructive testing (NDT) of metal casings through the eddy-current property. However, restricted by bad downhole conditions, the simple increase of the receiving array is not sufficient enough for improving the downhole NDT performance. In this paper, we present a multiple-transmit focusing (MTF)-based borehole TEM system for the NDT of downhole casings. On the basis of the borehole TEM signal model, the response of the multiple-transmit array is derived by employing the matrix form of the borehole TEM response. It was shown that the excited magnetic field by the multiple-transmit array can be focused by weighting the current of each transmitter. Using this property, a modified linear constrained minimum variance-based multiple-transmitting array weighting method was proposed to realize the MTF. Moreover, a subarray partition approach was proposed to simplify the MTF realization, where the subarray weighting and mean square error were also analyzed. The MTF method performance was verified by applying it to a borehole TEM system for the NDTs of downhole casings. Finally, simulations and experiments were conducted, and the results demonstrated the effectiveness of the proposed method.

In order to improve the power quality of the power transmission system, engineers must measure the phase angle of the transmission line to evaluate the power quality. Therefore, this article measures the phase angle by measuring the real-time voltage signal and current signal of the single-phase transmission line. This design is considered from the two aspects of hardware and software as well as the upper computer and the lower computer cooperate to test. The whole system uses ARM as the core to measure and process the parameters of the transmission line, which combined with the characteristics of ARM for signal acquisition, analog-to-digital conversion, data processing. The lower computer uploads it to the upper computer MATLAB for programming calculation through serial communication, and it uses the cross-correlation function method to measure the phase angle between voltage and current to meet the design requirements. The above design has been proved through experiments that it can be applied to engineering practice. The cross-correlation function algorithm in MATLAB closely fits the measurement of the phase angle of the transmission line. It proposes a new method for the measurement of the phase angle and lays a solid foundation for the future phase angle optimization.

In all links of natural gas supply, storage and marketing, accurate measurement of flow is one of the most critical links. Due to the high requirements of gas flow measurement for the flow meter measurement system, not only high accuracy of the flow meter measurement is required, but also higher requirements for the measuring sensor. Therefore, this paper mainly studies the influence of sensor structure design and sensor drive waveform on the signal sent and received by the gas flowmeter in the process of natural gas supply. Through the analysis and research of the ultrasonic attenuation theory, the conclusion that the performance of the oblique probe sensor is better is obtained. And by analyzing the experimental data, it is verified that the sensor effect of the oblique probe driven by the pulse waveform in the driving circuit is the best.

Borehole transient electromagnetic (TEM) techniques are widely used for nondestructive evaluation (NDE) of oil & gas well casings with eddy-current diffusion properties. In this paper, we present a multiple-eccentric-sensor-based borehole TEM system for NDE of downhole casings. Using the borehole TEM signal model, the TEM responses of sensors with eccentric transmitting coils are analyzed. The response of the eccentric sensor contains sensitive information in the direction of eccentricity while offering an improved detection performance. Hence, multiple eccentric sensors at different azimuthal angles are used to image casing damage, allowing directional NDE of downhole casings to be realized while improving the inspection resolution of the casing circumference. The effectiveness of the proposed method is verified by applying it to NDE of oil & gas well casings in the Shengli Oilfield. The experimental results demonstrate that the proposed method can effectively realize directional NDEs of downhole casings and improve the detection performance of the borehole TEM system.

Background:Sand production is an important factor affecting reservoir exploitation. Excessive sand production affects the oil well life, causes the damage to the oil recovery device and brings serious hidden danger in the process of safety production.Objective:This paper presents a sand content computation model for the crude oil, which uses the power of sand production and Parseval theorem, develops a system to monitor the sand content.Method:The main problem of designing the mechanical structure and matching layer for sand sensor is introduced. Furthermore a contactless Doppler ultrasonic method is used to develop sand amount detection system‚ finally the system measurement accuracy is calibrated by the developed calibration system.Conclusion:The sand production computation model can describe the relationship between sand monitor output and sand amount; compute the oil sand carrying ratio. The sand sensor is installed on the outside of pipe, not directly contacted with the sand particles. Measurement accuracy of the sand production is higher than the same type instrument.

Sand production is a critical issue during oil and gas production from sandstone reservoirs. Uncontrolled sand production not only poses the risk of well failure, but also can cause extensive damage to surface and subsurface facilities such as tubing, pumps, valves and pipelines. In recent decades, research on sand production has been conducted in several fronts including sanding prediction, sand monitoring, sand control and well-bore integrity analysis to prevent or alleviate sand production and its consequences. This paper mainly focuses on sand monitoring based on non-intrusive ultrasonic sensor which produces real-time information that can be used for maximizing the safe production of hydrocarbon. We used non-intrusive ultrasonic sensor to monitor the acoustic signals generated by sand particles impacting the pipe wall, and developed a methodology for processing acoustic signals based on the kinetic energy of sand particles in the pipeline. Further, we developed a procedure for identifying and filtering acoustic noise from unrelated events. We validated the proposed methodology for signal processing against experimental data. The results indicated that the de-noising algorithm could filter out the noise from the acoustic data and the model was effective for assessing the sand rate.

Transient electromagnetic (TEM) techniques are widely used in the field of geophysical prospecting. In borehole detection, the nondestructive inspection (NDI) of a metal pipe can be performed efficiently using the properties of eddy currents. However, with increasing concern for safety in oil and gas production, more than one string of pipe is used to protect wellbores, which complicates data interpretation. In this paper, an auxiliary sensor-based borehole TEM system for the NDI of multipipe strings is presented. On the basis of the characteristics of the borehole TEM model, we investigate the principle behind the NDI of multipipe strings using multiple time slices of induced electromotive force (EMF) in a single sensor. The results show that the detection performance of NDI is strongly influenced by eddy-current diffusion in the longitudinal direction. To solve this problem, we used time slices of the induced EMF in both the main and auxiliary sensors. The performance of the proposed system was verified by applying it to an oil well with a production casing and liner. Moreover, field experiments were conducted, and the results demonstrate the effectiveness of the proposed method.

This paper introduces in detail the TMCS simulator in the Measurement while drilling system of rotary steering drilling tool in ground simulation Experiment system. Focusing on of TMCS measurement and control simulator, and the realization of steering drilling measurement simulation test system principle of work process KEYWORD: Steering drilling; TMCS measurement and control simulator; Measurement system of steering drilling; Ground simulation Experiment International Conference on Social Science, Education Management and Sports Education (SSEMSE 2015) © 2015. The authors Published by Atlantis Press 1049 target motion characteristics simulation. Selected TMCS measurement and control simulator consists of pre-positioning data steerable drilling threedimensional trajectory, WOB and torque drilling parameters such as generators and computer subsystems. The drilling parameter produce a variety of mixed uses a dedicated data signal modulation scheme, which can effectively reduce the direct digital synthesis technology brought drift, dislocation and loss. Control process shown in Figure 1. Figure 1. TMCS control process On the workstation simulator programming movement characteristics of rotary steering drilling assembly can also be preset orbit stored in document form workstation simulator, the simulator will be run in accordance with the information stored threedimensional simulation of down-hole drilling trajectory. 3 SIMULATED TEST STEERING DRILLING SYSTEM COMPONENTS AND WORKING PRINCIPLE The ground simulation experiment for in steering drilling measurement system, that components shown in Figure 2. The simulation system works as follows. Receive commands and Decoding module 地面 井下 Ground simulation computer Ground command transmission module Workstation simulator Negative mud pressure pulse signal Mud pressure positive pulse signa Analog generator for Inclination, azimuth, tool face angle, WOB drilling parameters Host PC (Down-hole control system) the measurement system of steering drilling Steering Drilling Servos Figure 2. Schematic diagram of steering drilling measurement system simulation experiment system Steering drilling system collects the real-time inclination, azimuth and tool face angle based on the output of the sensor data with from measurement data model of the workstation simulator , and analog outputs sent to the host PC (the down-hole control center),Which of the control software to collect data based on the real-time input wellbore trajectory calculation, measurement and steering drilling system solver of inclination, azimuth and tool face angle information were to do the filtering. Then inclination, azimuth and tool face angle deviation with the output of the state variable filter, will feedback to steering drilling measurement system solver error correction, ground simulation computer real-time acquisition host computer (the underground control center) of the D / A output, in a way to get uploading these amendments of the host computer (down-hole control center) by the downhole mud pressure pulse signal, and according to the mathematical model of the D / A output and a steering servo mechanism, solving actual servo movement at this time, feeding rotary steering drilling of BHA model for controlling motion to calculate the angular velocity of the solution, attitude, position, velocity and acceleration information, converted into real-time drilling parameters which ground engineers need ,and to be ground control instructions that were encoded for transferring by mud pressure module negative pulse signals. To be received with decoder module into digital signals, eventually propagat to the host computer for analysis and processing, control commands can be manipulated to manipulate steering drilling servo mechanism, in order to achieve automatic control rotary steering drilling. 4 CASE HISTORY: APPLICATION VERIFICATION AND GROUND SIMULATION RESULTS 4.1 Ground simulation computer HMI Shows the overall status of the system, can be set to synchronize the time to ensure on synchronization ground simulation computer and down-hole in realtime clock. Easy to storage and cleanup the historical data, remove historical data; Isoperimetric element of display operating temperature from down-hole BHA, rotating state, inclination, while the builtnegative mud pressure pulse control instructions. Figure 3. Ground simulation computer HMI Inclination, azimuth, tool face angle, drill press and other drilling parameters generator Encoder / decoder Workstation simulator CAN bus Negative mud pressure pulse signal

While the insensitive of new slapper detonator ensuring the security, it proposes some special requirements on initiating conditions that metal foil may detonate in specific high voltage and high impulse current. But generation of high impulse current increases not only the technical difficulty of the power, but also the volume, power consumption and cost of the entire system. This article presents an approach to generate high impulse current with utilization of low-energy power. The theoretical calculation and experimental results show that higher measurement current can be generated in this method. By application of the technique in the intensive initiating system can detonation be real-time and reliable as well as improve the security of the system. Therefore, it owns certain theoretical and practical value.