When entering an anisotropic formation, a shear wave splits into a fast wave and a slow wave. Based on the principle of four-component cross-dipole acoustic wave measurement, the anisotropy of HTI （Horizontal Transve...When entering an anisotropic formation, a shear wave splits into a fast wave and a slow wave. Based on the principle of four-component cross-dipole acoustic wave measurement, the anisotropy of HTI （Horizontal Transverse Isotropy） formation can be determined. The method of calculating the fast and slow wave data when a shear wave propagates along the borehole axis in anisotropic formation was analyzed, and the implementation of a cross-dipole acoustic logging tool was demonstrated. The tool was composed of transmitter electronics, transmitter mandrel, acoustic isolator, receiver mandrel and main control electronics. Sonde, transmitter circuit, signal receiving and processing circuit, data acquisition system, system control circuit and telemetry interface circuit were presented and analyzed. The test model was used in production wells and standard wells in various areas and the four-component cross-dipole waves were acquired and processed. The waves had good signal-to-noise ratio and clear characteristics, and the fast and slow waveforms, processed slowness curves, anisotropy and fast shear wave azimuth well matched with each other.展开更多
Tool condition is one of the main concerns in friction stir welding （FSW）, because the geometrical condition of the tool pin including size and shape is strongly connected to the microstrueture and mechanical perfor...Tool condition is one of the main concerns in friction stir welding （FSW）, because the geometrical condition of the tool pin including size and shape is strongly connected to the microstrueture and mechanical performance of the weld. Tool wear occurs during FSW, especially for welding metal matrix composites with large amounts of abrasive particles, and high melting point materials, which significantly expedite tool wear and deteriorate the mechanical performance of welds. Tools with different pin-wear levels are used to weld 6061 Al alloy, while acoustic emission （AE） sensing, metallographic sectioning, and tensile testing are employed to evaluate the weld quality in various tool wear conditions. Structural characterization shows that the tool wear interferes with the weld quality and accounts for the formation of voids in the nugget zone. Tensile test analysis of samples verifies that both the ultimate tensile strength and the yield strength are adversely affected by the formation of voids in the nugget due to the tool wear. The failure location during tensile test clearly depends on the state of the tool wear, which led to the analysis of the relationships between the structure of the nugget and tool wear. AE signatures recorded during welding reveal that the AE hits concentrate on the higher amplitudes with increasing tool wear. The results show that the AE sensing provides a potentially effective method for the on-line manitoring of tool wear.展开更多
This paper presents a debugging system for multi-pole array acoustic logging （MPAL） tools. The debugging system proposed in this study can debug the MPAL tool system, sub-system and local electronics. In the test eq...This paper presents a debugging system for multi-pole array acoustic logging （MPAL） tools. The debugging system proposed in this study can debug the MPAL tool system, sub-system and local electronics. In the test equipment, we have used principal and subordinate structures, and interconnected the host computer and the front-end machine via Ethernet. The front-end machine is based on the ARM7 （advanced reduced instruction set computing （RISC） machine） technique, the processor of which runs an embedded operating system, namely, uClinux OS. We have analyzed the system telecommunication, human-machine interface circuit, transmitter mandrel interface circuit, receiver mandrel interface circuit, and board-level test interface circuit. The software used in the system consists of the embedded front-computer software and the host application software. We have explained in detail the flow chart of the boot loader in the embedded front-computer software. The host application software is composed of four application subroutines, which match with the functional modules of the system hardware. A net communication program based on the server^client mode is implemented by means of socket programming and multi-thread programming. Test results indicate that the data transmission rate of the system is higher than 1 MB/s, which completely meets the current requirements of the data transmission rate between the tool system and the wireline telemetry device. Application of the debugging system, which includes multiple level test methods, shows that the proposed system can fully meet the test requirements of MPAL at various levels.展开更多
The transmitting properties of acoustic emission(AE) signal is investigated in order to provide experimental basis for application of AE technique. In the paper, the influences of the geometric shape and material prop...The transmitting properties of acoustic emission(AE) signal is investigated in order to provide experimental basis for application of AE technique. In the paper, the influences of the geometric shape and material properties of the mediums and the bearing type on AE transmission are analyzed for providing the theoretic foundation for selecting the transmission route of AE signal and the fixing location of the AE sensor reasonably. According to the transmitting properties of AE, an apparatus of detecting AE signal for the tool breakage monitoring system has been set up. Its application results show that it is of benefit to improving the sensitivity of the tool breakage monitoring system.展开更多
文摘When entering an anisotropic formation, a shear wave splits into a fast wave and a slow wave. Based on the principle of four-component cross-dipole acoustic wave measurement, the anisotropy of HTI （Horizontal Transverse Isotropy） formation can be determined. The method of calculating the fast and slow wave data when a shear wave propagates along the borehole axis in anisotropic formation was analyzed, and the implementation of a cross-dipole acoustic logging tool was demonstrated. The tool was composed of transmitter electronics, transmitter mandrel, acoustic isolator, receiver mandrel and main control electronics. Sonde, transmitter circuit, signal receiving and processing circuit, data acquisition system, system control circuit and telemetry interface circuit were presented and analyzed. The test model was used in production wells and standard wells in various areas and the four-component cross-dipole waves were acquired and processed. The waves had good signal-to-noise ratio and clear characteristics, and the fast and slow waveforms, processed slowness curves, anisotropy and fast shear wave azimuth well matched with each other.
文摘Tool condition is one of the main concerns in friction stir welding （FSW）, because the geometrical condition of the tool pin including size and shape is strongly connected to the microstrueture and mechanical performance of the weld. Tool wear occurs during FSW, especially for welding metal matrix composites with large amounts of abrasive particles, and high melting point materials, which significantly expedite tool wear and deteriorate the mechanical performance of welds. Tools with different pin-wear levels are used to weld 6061 Al alloy, while acoustic emission （AE） sensing, metallographic sectioning, and tensile testing are employed to evaluate the weld quality in various tool wear conditions. Structural characterization shows that the tool wear interferes with the weld quality and accounts for the formation of voids in the nugget zone. Tensile test analysis of samples verifies that both the ultimate tensile strength and the yield strength are adversely affected by the formation of voids in the nugget due to the tool wear. The failure location during tensile test clearly depends on the state of the tool wear, which led to the analysis of the relationships between the structure of the nugget and tool wear. AE signatures recorded during welding reveal that the AE hits concentrate on the higher amplitudes with increasing tool wear. The results show that the AE sensing provides a potentially effective method for the on-line manitoring of tool wear.
基金supported by the Fundamental Research Funds for the Central Universities and the National Hi-tech Research and Development Program of China (863 Program) (Grant No. 2007AA06Z232 )
基金supported by National Science Foundation of China (61102102, 11134011, 11204380 and 11374371)Major National Science and Technology Projects (2011ZX05020-002)+2 种基金PetroChina Innovation Foundation (2014D-5006-0307)Science and Technology Project of CNPC (2014A-3912 and 2011B-4001)the Foundation of China University of Petroleum (KYJJ2012-05-07)
文摘This paper presents a debugging system for multi-pole array acoustic logging （MPAL） tools. The debugging system proposed in this study can debug the MPAL tool system, sub-system and local electronics. In the test equipment, we have used principal and subordinate structures, and interconnected the host computer and the front-end machine via Ethernet. The front-end machine is based on the ARM7 （advanced reduced instruction set computing （RISC） machine） technique, the processor of which runs an embedded operating system, namely, uClinux OS. We have analyzed the system telecommunication, human-machine interface circuit, transmitter mandrel interface circuit, receiver mandrel interface circuit, and board-level test interface circuit. The software used in the system consists of the embedded front-computer software and the host application software. We have explained in detail the flow chart of the boot loader in the embedded front-computer software. The host application software is composed of four application subroutines, which match with the functional modules of the system hardware. A net communication program based on the server^client mode is implemented by means of socket programming and multi-thread programming. Test results indicate that the data transmission rate of the system is higher than 1 MB/s, which completely meets the current requirements of the data transmission rate between the tool system and the wireline telemetry device. Application of the debugging system, which includes multiple level test methods, shows that the proposed system can fully meet the test requirements of MPAL at various levels.
基金Supported by the Laboratory of Robotics, Chinese Academy of Sciences
文摘The transmitting properties of acoustic emission(AE) signal is investigated in order to provide experimental basis for application of AE technique. In the paper, the influences of the geometric shape and material properties of the mediums and the bearing type on AE transmission are analyzed for providing the theoretic foundation for selecting the transmission route of AE signal and the fixing location of the AE sensor reasonably. According to the transmitting properties of AE, an apparatus of detecting AE signal for the tool breakage monitoring system has been set up. Its application results show that it is of benefit to improving the sensitivity of the tool breakage monitoring system.
