M1080B无心外圆磨床改进

M1080B无心外圆磨床砂轮及导轮宽度较窄,磨削轴承套圈外圆时,磨削效率低,托板架调整较为繁琐、皮带打滑、磨损较为严重。针对上述问题,提出了相应的解决办法,提高了磨削效率。     

埋地管道泄漏内封堵装置设计与研究

针对流体输送埋地管道泄漏问题,设计了一种利用管道机器人携带封堵气囊进行快速应急封堵修复的埋地管道泄漏内封堵装置。采用矩阵变换方法建立了牵引系统驱动轮过弯方程,利用MATLAB软件对过弯方程进行了验证,同时利用ADAMS软件仿真分析过弯路径与驱动轮转角对牵引系统行走速度的影响。研究结果表明:由两个串联封堵器组成的应急封堵系统可满足复杂工况下的管道泄漏封堵要求;牵引系统驱动轮在弯管内部行走时,单轮速度呈周期性变化,但三个驱动轮整体周期运动特性一致;驱动轮转角在25°~40°时,牵引系统行走速度与驱动轮转角成正比,且转角为30°时驱动效果最好。该内封堵装置的结构设计可为管道泄漏应急封堵领域装备的研发提供重要参考。     

Effect of grinding-induced cyclic heating on the hardened layer generation in the plunge grinding of a cylindrical component

This paper discusses the effects of the grinding-induced cyclic heating on the properties of the hardened layer in a plunge cylindrical grinding process on the high strength steel EN26. It was found that a multi-pass grinding brings about a uniform and continuous hardened layer along the circumference of the cylindrical workpiece. An increase of the number of grinding passes, leads to a thicker layer of hardening, a larger compressive residual stress and a deeper plastic deformation zone. Within the plastic deformation zone, the martensitic grains are refined by the thermo-mechanical loading, giving rise to a hardness of 12.5% higher than that from a conventional martensitic transformation. The coupled effects of heat accumulation and wheel wear in the multi-pass grinding are the main causes for the thickening of the hardened layer. A too small infeed per workpiece revolution would result in insufficient grinding heat, and in turn, bring about an undesirable tempered hardened layer and a reduction of its hardness.     

采油树平板闸阀柔性密封圈结构优化设计

为了提高采油树平板闸阀密封圈的密封性能,在泛塞封的基础上,设计一种密封圈本体唇边开有锯齿状凸起的新型柔性密封结构;运用有限元分析方法模拟密封圈的工作状况,分析柔性密封结构特性参数对密封圈密封性能的影响,获得不同柔性密封圈结构参数下密封面间接触应力分布规律,并对新型密封结构进行优化。结果表明:密封面间最大接触应力随唇边锯齿数量、唇边夹角度数的增大而增大,随唇谷夹角度数的增大而减小;新型密封结构选择锯齿数量为3、唇边夹角为20°、唇谷夹角为30°的特性参数时,其最大接触应力比常规Y形密封圈提高了15倍;新型柔性密封结构的密封圈与阀杆、阀盖壁面间接触应力比常规Y形密封圈有显著提高,提高了密封圈的密封性能。     

Dynamics of liquid-filled spacecraft

A method is presented for simulating coupled liquid-solid dynamics. An important example of a coupled liquid-solid system is a satellite carrying fuel. The dynamics of the satellite and the onboard fuel influence each other, which may lead to satellite motion that is uncontrollable. For better understanding of the complex dynamics of coupled systems, a numerical model is developed. The model consists of two parts. The first part that solves the liquid motion is only briefly discussed here. The focus in this paper is on the way in which the dynamics of the liquid and the solid body are coupled. For this, the governing equations are presented in which terms appear that represent the force and torque on the solid body due to the sloshing liquid. The governing equations are rewritten such that the discrete approximation of these equations can be integrated in a stable manner for arbitrary liquid/solid mass ratios. Results are presented demonstrating the stability of the present model. A grid-refinement study and a time-step analysis are performed. Finally, the flat-spin motion of a satellite, partially filled with liquid, that flew in 1992 as part of the Wet Satellite Model experiment is studied. Results from the simulation are compared with the actual flight data.     

哈得逊隆起下石炭统基准面旋回与储集层预测

依据基准面旋回原理和方法,综合利用哈得逊地区的钻井、测井、地震以及地球化学资料,在研究区下石炭统识别出1个Ⅰ型和3个Ⅱ型层序界面,将哈得逊地区下石炭统划分为3个中期基准面旋回：SC1、SC2、SC3,对应于早石炭世海侵的3个海进-海退旋回.SC1旋回以滨岸砂坝沉积为主,而SC2、SC3旋回发育潮坪沉积体系.研究认为,SC1旋回滨岸砂岩及SC2下降半旋回的潮间带薄层砂岩为有利储集砂体,是地层-岩性型油气藏的重点勘探目标.     

一维ZnO纳米结构的电子场发射研究

在大量制备一维ZnO纳米结构的基础上,研究了这些纳米结构的场发射性能。对于四角状ZnO纳米结构,获得1.0m Ac/m2的电流密度只需要4.5V/μm的电场;对于线状Z nO纳米结构,获得1.0mAc/m 2的电流密度需要6.5V/μm的电场。由于其特殊的结构,四角状ZnO一维纳米结构在真空电子器件方面有很好的应用前景。     

冲切成槽法在薄壁砼防渗墙施工中的应用

冲切成槽法施工薄壁砼防渗墙,是一种新型防渗墙施工方法,它是利用特制的扁钻头对风化基岩或卵石层进行冲切成槽的施工方法,在工艺上有着较强的优越性.     

基于16位单片机的电磁平板硫化机控制系统

介绍一种基于 16位单片机的电磁平板硫化机控制系统,该系统能有效地提高现场控制的实时性和程序运行的稳定性     

WQ—10型煤气平焰烧嘴的半工业性试验研究

对ＷＱ－１０型煤气平焰烧嘴进行半工业性试验，得到了该烧嘴较长时间运行下的一些性能。结果表明，该烧嘴平火焰稳定，炉顶温度分布均匀，燃烧烟气中ＣＯ、ＮＯ含量达到了ＹＢ／Ｔ０６２－９４标准的要求。