基于偶极横波资料的火山岩裂缝及油气识别

火山岩油气藏已成为重要的油气勘探目标和储量增长点.在火山岩的地层评价中,裂缝与油气识别一直是一个核心问题.针对地层矿物成分与岩性十分复杂、常规测井方法很难准确快速识别,应用声波能量衰减对于天然裂缝极为敏感特性,利用斯伦贝谢偶极横波资料可以计算纵、横波及斯通利波能量衰减的特性,实现对裂缝的有效识别.在岩性、物性等因素基本一致的条件下,利用纵、横波能量重叠、泊松比、波速比还可以较好地识别气层.克拉玛依火山岩地层的实际应用效果表明,偶极横波资料在火山岩地层评价中具有十分重要的作用,为火山岩地层裂缝与油气识别开辟了新的途径.     

偶极横波资料在低孔低渗储层改造中的应用

水力压裂至今一直是低孔渗储层改造的最有效措施。为了提高低孔渗油田压裂开发的整体效益和效果,为油层改造有针对性地提供施工层位和准确的储层参数,本文以胜利油气区渤南-孤北地区中生界、上古生界的低孔低渗储层为研究目标,探索、研究偶极横波测井资料在低孔低渗储层评价及改造中发挥的作用。本文充分利用偶极横波测井资料提供的纵、横波数据,结合其他常规测井资料及压裂、试油资料,建立适合本区低孔低渗油藏特性的岩石力学参数计算模型和压裂预测模型,对所改造层位进行压裂高度及施工压力参数预测,为优选压裂层位和方案设计提供依据。现场应用表明,本文提出的方法预测结果与现场压裂、试油验证结果一致性较好。     

HD seis VSP测井仪DSI和STD箱体故障及解决方法

DSI箱体和STD箱体是HD seis VSP测井仪器的核心部件,维持其正常运转是保障井下设备安全工作的前提。针对DSI箱体出现的故障,应结合DSI控制电路图,锁定故障元器件,分别在配件充足和不足两种情况下进行处理。STD箱体的硬盘故障和电池故障有别于常规计算机,解决其故障的方法是遵循特点,做硬盘更换和系统安装,并重新设置引导系统,使系统进入正常运转。     

数字话路倍增技术

数字话路倍增设备(DCME)是IDR业务中的主要特色之一。本文首先介绍了DCME的基础原理,然后简要介绍了其相关技术的发展情况。     

基于偶极横波测井资料预测储层压裂缝几何参数

利用偶极横波测井资料算出泊松比、弹性模量和最小水平主应力等岩石力学参数,基于IVERSON模型首先估算射孔层段压裂缝延伸高度,通过工区储层各向异性系数与裂缝宽度的回归关系估算裂缝宽度,根据椭球体积模型并结合压裂液的利用率及加砂量估算裂缝的径向延伸长度。将该方法优化编程,用于处理工区压裂前后井的测井资料,对比分析预测结果与实际压裂效果,两者较为一致,表明该方法效果明显,值得推广应用。     

基于EMD的局部放电窄带干扰抑制算法

以经验模态分解(empirical mode decomposition,EMD)为基础,提出了一种基于包络线及有效值的自适应窄带干扰抑制算法,用以从噪声中提取局放信号。EMD可以自适应地将信号分解成若干阶不同频率段的固有模态函数(intrinsic mode functions,IMF),窄带干扰经分解后在振幅上显示出与局放脉冲明显不同的特征,通过包络线及有效值确定的阈值可以有效地区别开来。仿真及实际处理结果表明:与常规的基于小波变换的窄带抑制算法相比,该算法具有较强的自适应性;能有效地抑制局放信号中的窄带干扰。     

基于DSI技术的水库静态库容快速计算

基于DSI技术的水库静态库容快速计算是通过采用DSI三维技术快速构建不规则三角网地形模型,再结合库容自动计算模块快速输出库容计算成果。该方法通过地形数据快速、准确地计算出不同蓄水位的水库静态库容及对应的蓄水面积,自动生成水位-库容-面积曲线,克服了现有水库静态库容计算中的缺点和不足,在水库静态库容计算领域提供了一种新的技术方案。     

偶极横波测井原理与应用

由于测井资料具有识别性强、连续性好、经济性高等特点,测井曲线成为求取连续地层岩性剖面和岩石力学参数剖面的最佳方法。但随着钻遇地层的日趋复杂,利用常规测井已无法准确、快速识别软地层矿物成分及岩性等信息。而偶极横波测井则能很好地解决以上问题。在充分调研了国内外相关文献的基础上对XMAC、DSI、WaveSonic测井仪原理进行了总结。分析了偶极横波测井发射与接收信号特征的关联关系,提出了如何求取快、慢横波波形信息及其方位的方法。充分利用偶极横波测井资料,可以使计算所得的岩石力学特性、地应力和地层三压力等更加精确。     

The die turning injection (DTI) process for the fabrication of hollow parts

The die turning injection (DTI) process, which can fabricate hollow plastic parts with a complex geometry, is proposed in this study. DTI is a new technology, which is accomplished in three steps: (1) the primary injection step, (2) the die turns, and (3) the secondary injection step. Two separate halves of the part are injection molded during the primary injection. The die rotates to align the two halves for the secondary injection. The secondary injection along the aligned surfaces joins the two halves into the final hollow part. The proposed DTI technology provides several advantages. It has the ability to form hollow parts with high dimensional accuracy, the equipment requires a small working space and the machine control is fairly simple. To verify the feasibility of DTI process, industrial trials were performed to manufacture a hollow nozzle part for a washing machine. To optimize the process, a finite element (FE) analysis was performed using the commercial code, Autodesk Moldflow Insight. To design the hot runner system for the primary injection step, two types of hot runner systems, a V-shaped and a T-shaped runner, were investigated. The critical parameter that was measured in these two runner designs was the amount of warpage. An FE analysis for the secondary injection step was also performed to analyze the flow characteristic at the aligned surfaces of the two separate hollow halves. The cooling channel was also designed to cool the mold and control the uniformity of injection temperature. With appropriate control of the injection conditions, a hollow nozzle part having excellent dimensional accuracy was successfully manufactured using the proposed DTI process.     

Direct strain tensor approximation for full‐field strain measurement methods

Full‐field strain measurement techniques are based on computing the spatial derivatives of numerical or functional approximations of the underlying displacement fields extracted from digital imaging methods. These methods implicitly assume that the medium satisfies the strain compatibility conditions, which are only true in the case of a continuum body that remains continuum throughout its deformation history. In the present work, we introduce a method that can be used to calculate the strain components directly from typical digital imaging data, without the need of the continuum hypothesis and the need for displacement field differentiation. Thus, it enables the measurement of strain fields from imaged surfaces that may or may not contain discontinuities. Numerical comparisons are performed on the basis synthetic data produced from an analytical solution for an elastically orthotropic open‐hole domain in tension. For performance comparison purposes, the mean absolute error distributions are calculated for the cases of both the traditional meshless random grid method, and the direct strain method introduced herein. It is established that the more refined representation of strain provided by our present approach is more accurate everywhere in the domain, but most importantly, near its boundaries. Published 2013. This article is a US Government work and is in the public domain in the USA.