【作者】 刘丽群；

【导师】 王明吉；

【作者基本信息】 大庆石油学院 ， 测试计量技术及仪器， 2009， 硕士

【摘要】 目前,石油生产中下井油管长度的测量,仍主要采用传统的人工拉皮尺的方法对每一根管柱进行测量和记录。这种方式从有油井那一天开始,一直沿用至今,不仅效率低,劳动强度大,而且测量精度差。有的油田除人工计量外,还需要再次用专用仪器测量井下工具的精确位置。即便有人提出利用声、光等方法进行测量,但是仍然因存在结构复杂、操作不便等诸多问题而未被广泛应用。显而易见,研究开发智能化的下井油管长度在线计量仪器不仅可有效提高油管的计量精度、减轻工人的劳动强度,而且可节约生产成本、提高生产效率和经济效益。激光多普勒测量技术以它精度高、线性度好、动态响应快、测量范围大、非接触测量等特点得到了广泛的应用和发展,尤其在流体流速测量方面取得了令人满意的效果。激光在线测长已成为当前LDV工业应用技术研究开发的重点。本文根据油田开发的实际需要,设计了一种基于激光多普勒测量原理的连续油管长度在线测量系统。该系统采用双光束型光路,以半导体激光器为光源、以光电倍增管作为光电探测器,通过接收运动油管表面的散射光,经数据采集和信号处理系统,测量出多普勒频移,最终可获得下井油管的长度。论文叙述了其测量原理以及各部分单元的设计与实现情况,为今后进一步的研究奠定了理论和实践的基础。这是将激光多普勒测速技术应用于下井油管长度测量的一种新的尝试。该系统研制成功,可望获得一种新的性能更加优越的连续油管长度在线测量装置。更多还原

【Abstract】 At present, workers still mainly use the traditional manual method to measure the length of oil tubes going down into wells in the oil production. They measure every tube by pulling a tape and record the total number. This way has been in use since wells emerged. Not only it is inefficient, labor-intensive, but also its measurement accuracy is low. In addition to manual measurement, some oil fields need to use special instruments to measure the exact location of downwell tools, again. Even if someone poposed to make use of sound, light or other methods to measure tubes length, but these methods or techniques have not still been widely applied because of low accuracy, complex structure and many other questions.Therefore, It is obvious that the research and development of online intelligent measurement apparatus for tubes going down, can not only improve the measurement accuracy, reduce labor intensity, but also save production costs, improve production efficiency and economic profits.Laser Doppler measurement technology is widely used and developed due to its many characteristics, such as high precision, good linearity, fast dynamic response, wide measurement range, as well as non-contact measurement, etc. Particularly in the fluid flow rate measurement the results are satisfactory. Laser online measurement technology has become a focus of the current industrial applications LDV technology research and development.In this thesis, according to the practical requirement, it is designed that an online length measuring system for continuous oil tubes based on the principle of Laser Doppler Velocimetry. This system takes dual-beam optical structure. It uses the semiconductor laser as light source, and takes the photomultiplier tube to receive the scattered lights from the surface of the moving oil tubes. Based on data acquisiting and signal processing system, we can measure the Doppler shift, and then calculate the length of the continuous oil tubes. The measuring system has some characteristics such as high precision, simple structure, stable performance, being suitable for the requirements of field operations, and so on. So it has a broad application prospect. The thesis describes the measurement principle and each unit design and implementation case. It laid the foundation of theory and practice for further research. This is a new attempt to use laser Doppler velocimetry measurement technology in measuring the length of continuous tubes. If the system is successfully developed, people can get a new kind of online length measurement equipment with more superior performance to continuous tubes.更多还原