The Research Of Instrument For Measuring Depth And Temperatures In Oil Well Based On Remote Digital Communication With High Accuracy

In the oil extraction, the engineer of oil want to know the exactitude curve of temperature—deepness in the oil well, hereby, they can analyze the trend of the oil well and forecast trend of production under diversified exploitation mode; the engineer of oil extraction also want to know the exactitude curve of temperature—deepness in the oil well, so they can exploit the oil in the prime trends condition. Thus, the metrical instrument of oil temperature and deepness is an absolutely necessarily instrument during the collection of rock oil.At the present time, the metrical instrument of oil temperature and deepness can divide to four kinds: mechanical metrical instrument, photoelectric metrical instrument, CCD metrical instrument, beamy metrical instrument .After analyze, we can found that metrical instrument of oil temperature of present phase subsist these problems:1 The ratio of capability and price is not high2 The currency of the metrical instrument of oil temperature and deepness is not well.3 The problem of data transmission.In order to solve these problems, I manufacture a new metrical instrument of oil temperature and deepness, which is based on remote digital communication with High Accuracy. In the following, I would like to give the design project of the metrical instrument:The system is divvied to several parts as followed: The unit of the sensor of deepness,Temperature sensors modules,The module of signal acquisition and transmission,The module of signal recognition and extraction.1. The unit of the sensor of deepnessIn order to solve the problem of the low measure precision of conventional metrical instrument of oil temperature and deepness, my laboratory designed a Casing Connector Logger. In this system, the unit of the sensor of deepness is made up of CCL and photoelectric part. The CCL can exactitude confirms the position of connector, and the distance of two connectors can measure by photoelectric part. The distance of two connectors is about 10m, so the elongate error can be ignored. Based on the measure in the locale, the method can achieve the require of design.2. Temperature sensors modulesPlatinum Resistance such as Pt1000,whose temperature coefficient of resistance has little dispersion,its features as followed:High accuracy,Linearity is good,Relatively high sensitivity. So in this research I used Pt1000 which has excellent performance as temperature sensors,it can meet the request in the system.3. The module of signal acquisition and transmissionI used AD7793 with 24-bit to acquisition the signal of deepness and temperature,the signal is treated by the SCM P87LPC769,and in the module of depth measurement , we used the mode of double-SCM. About the communications,my laboratory designed the digital communication methods for remote by armored cable,and its armoring as ground,the armored cable not only for power supply but also for communication. So it can save the conduit for digital communication,and compared with Multi-core cable in the same diameter,it can also save cost.4. The module of signal recognition and extractionThe worker above ground equipment resaves the signals of deepness and temperature by MAX232,Owing to equipment and wells in the ongoing process of decentralization wall collisions, it produces a lot of interference signals. It designs a filter circuit in hardware and uses a digital composite filter algorithm in software, but these two methods can not filter out the noise caused by collisions after the actual measurements. To solve this problem, I also used the methods of Fuzzy Cluster Analysis to eliminate the interference signals,and so can receive the Exact signals. And at the field experiment,the system can meet the request completely.