采用428XL仪器实现高保真可控震源三维地震采集

428XL地震仪器系统成功实践了一种新的可控震源施工技术和方法——高保真可控震源采集技术（HFVS）。本质上，HFVS技术是以采集到的每台震源实际运动的信号来进行数据反演，替代了传统的以参考信号进行的互相关处理，从而有效地减少了谐波畸变对地震资料品质的影响。在实际施工时，HFVS技术采用多台震源以不同初始扫描相位同时激发，再将采集到的地震记录进行分离处理得到每台震源的大地脉冲响应，实现了高效采集条件下的可控震源单点激发。本文详细介绍了HFVS技术的基本原理，总结了高保真可控震源采集的施工特点及其对仪器采集设备的要求，并通过实例，介绍了利用428XL仪器先进的技术性能实现高保真可控震源三维地震采集的方法和经验。     

一阶滞后对象的温度控制

本文主要介绍了利用μ XL中小型集散控制系统,对未知参数的一阶惯性滞后对象,实现温度控制,并得到理想的温度控制曲线。     

Friction and wear behaviour of Thordon XL and LgSn80 in sliding against plasma-sprayed Cr2O3 coatings

This paper studies the friction and wear behaviour of two important bearing materials, Thordon XL and LgSn80, in dry and lubricated sliding vs. plasma-sprayed Cr₂O₃ coatings. As a reference, AISI 1043 steel is also studied under the same conditions. SEM, EDS and surface topography were employed to study the wear mechanisms. The results indicate that the Thordon XL/Cr₂O₃ coating pair gives the lowest dry friction coefficient (0.16) under a normal load of 45.3 N (pressure 0.453 MPa) at a velocity of 1 m/s. The dry friction coefficient of Thordon XL/Cr₂O₃ coating increases to 0.38 under a normal load of 88.5 N (pressure 0.885 MPa). The dry friction coefficients of the LgSn80/Cr₂O₃ coating are in the range of 0.31–0.46. Secondly, both dry wear rate under low normal load (45.3 N) and lubricated wear rate under a load of 680 N for Thordon XL are lower than those of LgSn80 in sliding against plasma-sprayed Cr₂O₃ coatings at a speed of 1 m/s. However, under a normal load of 88.5 N the dry wear rate of Thordon XL is much higher than that of LgSn80. Thirdly, a high viscosity lubricant (SAE 140) leads to lower wear for Thordon XL and LgSn80 than a low viscosity lubricant (SAE 30). Finally, the dominating wear mechanism for Thordon XL is shear fracture when against the plasma-sprayed Cr₂O₃ ceramic coating. For LgSn80 against plasma-sprayed Cr₂O₃ ceramic coating, abrasive wear is the governing failure mechanism.     

428XL光缆交叉线的工作原理及故障检修方法

428XL光缆交叉线是428XL仪器的重要组成部分,它的问世有效提高了采集数据的传输速度,满足了随着野外采集道数的增加采集数据的数据量越来越大的数传要求。本文从428XL光缆交叉线的基本组成入手,详细剖析了428XL光缆交叉线的传输原理,并介绍了光缆交叉线应用于428XL仪器施工时的工作流程及其在施工中可能出现的故障和相应的检修方法。     

Performance of supercritical carbon dioxide sprays as coolants and lubricants in representative metalworking operations

This paper investigates the cooling and lubrication properties of supercritical carbon dioxide (scCO₂) sprays as potential substitutes for aqueous emulsions and straight oils used in the metalworking industry today. Sprays of rapidly expanding scCO₂ act to cool and lubricate machining and forming processes by delivering a mixture of dry ice and lubricant deep into the cutting/forming zone. In this work, experiments with turning, milling, drilling, thread cutting, and thread forming were performed with scCO₂ and other metalworking fluids (MWFs) to evaluate their relative performance with respect to tool wear and machining torque. Observations reveal that scCO₂–MWFs are more effective in removing heat from the tool-workpiece interface than conventionally delivered (flood) aqueous MWFs as well as other gas-based MWF sprays. In addition, scCO₂–MWFs delivered in lubricant-expanded phase, where scCO₂ is used to increase volume of lubricant in the spray field, are shown to provide better lubricity than straight oils and oil-in-air minimum quantity lubrication (MQL) sprays. As a result, scCO₂–MWFs can reduce tool wear and improve machining productivity in a wide range of manufacturing operations leading to appreciable improvements in the economics of manufacturing. Also given that CO₂ is a recovered waste gas that is non-toxic, scCO₂–MWFs can improve the environmental and worker health performance of manufacturing operations.     

428XL无线采集设备的应用

LAUR和LRU是428XL仪器的无线采集设备单元。在Link排列中合理应用无线采集设备，可以克服地震采集施工中采用有线而无法逾越的障碍。本文介绍了LRU、LAUR的功能和设置方法，总结出了它们在几种不同复杂地形下的使用方式、方法以及应用中需要注意的问题。     

G3i及428XL数字地震仪的引进与管理

为了更好地参与市场竞争,更高效、高精度地完成地震勘探项目,针对物测队现有设备的实际情况,经过反复调研和考察,决定引进目前全球最先进的美国INOVA公司G3i高容量有线地震采集系统和法国Sercel公司428XL数字地震仪各两套,以增强煤田地震勘探的装备实力,从而高效、高质量地完成野外数据采集任务。     

428XL仪器采集链的使用、维护和现场简易维修

428XL仪器在可靠性、可操作性以及传输速度都得以提升的同时,其采集链由几段独立的电缆整合为一条整链,在野外检修采集链时,可能因为没有专用检测设备而无法按检修手册进行维修。本文讨论了WPSR和ST两种常用采集链在野外使用时,根据不同的地表条件有针对性采取的不同保护措施;并提出了适合于野外条件下进行采集链简易、快速维修的方法。     

428Lite便携式遥测地震数据采集系统简介

428Lite便携式遥测地震数据采集系统是2006年初推出的小型便携式采集系统。该系统运用了当今最先进的计算机、网络和微电子技术,采用脉冲震源,可以全面兼容428XL标准型仪器的功能,且体积小、重量轻,更适应于原始丛林、山地等极复杂地表的地震勘探。本文简要介绍了428Lite的基本组成、技术参数及其安装、设置的方法,并将它与428XL在野外使用的情况进行了对比。     

地震勘探仪器在高密度采集中的应用

本文分析了高密度地震采集对地震仪器的基本技术要求,总结了目前几种先进的地震勘探仪器的性能和技术特点,以及国内使用这几种仪器进行高密度勘探的情况.先进的地震勘探仪器是高密度采集获得理想地质目标的基础,文中结合典型高密度采集项目展示了当今地震勘探仪器在高密度采集中的重要作用.