试制STM-R80钻探用无缝钢管

采用42MnMo7、41MnV5钢锻坯,经热轧穿孔、冷拔加工,试制出STM-R80地质钻探管。该地质管经检验和使用,质量符合要求。介绍了钢的化学成分、试制的主要工艺过程及其参数。     

陕甘宁气田～银川输气管线阴极保护有效性评价

本文通过对陕甘宁气田～银川输气管线阴极保护系统调查、管/地电位及开/关电位测试,分析确定出管线所经地区土壤IR 降值,并对阴极保护效果做出评价。     

高速摄影法研究铅芯延期体的燃烧特性

用高速摄影仪对卡在透明塑料管中的铅芯延期体从点火到喷火的过程进行了拍摄.图像显示,在铅芯延期体点火端有一段延期药与点火药头一起在很短的时间内完成燃烧过程;在铅芯延期体喷火端有一段延期药被喷出,铅芯延期体未起延期作用.将燃烧后的铅芯延期体沿药芯切开,显微镜下观察残渣,发现有的残渣呈层状龟裂.根据结果,对这些影响铅芯延期精度的因素进行了分析.     

Effects of Working Fluid,Tubeside Enhancement and Bundle Depth on the Optimized Fin Geometry of a Horizontal Condenser Tube

A theoretical study has been made to optimize the fin geometry of a horizontal finned tube which is to be usedfor condensers that handle the vapor load of a liquid phase change cooling module.Systematic numerical calcu-lations of the vapor to coolant heat transfer have been performed for parametric values of fin height,fin spacing,vertical bundle depth and tubeside heat transfer coefficient.Three dielectric fluids (R-113,FC-72,and FC-87)at atmospheric pressure were selected as the working fluids.For a single tube with optimized fin geometry,theaverage heat flux increased in the order of FC-87,R-113 and FC-72.Both the optimum fin height and optimumfin spacing increased with increasing vertical bundle depth.     

Diffusion Behaviour of Fe-Cu Interface of Copper Brazed Double-wall Steel Tubes

By means of electron probe(EPMA),scanning electron microscope(SEM),and optical microscope(QM),the diffusion behaviour on the Fe-Cu interface of copper brazed double-wall steel tubes andthe microstructure of the diffusion layer have been investigated.There are three kinds of metallurgicalbonds between copper plating layer and steel substrate: (1)the Cu diffusing into steel substratealong grain boundary of ferrite;(2)the Cu diffusion into grain bulk of ferrite: (3)the Fe diffusing intoCu layer.The copper brazed double-wall steel tubes are formed by the combination of the diffusionsmentioned above and this is the reason for excellent mechanical and technological properties of thecopper brazed double-wall steel tubes.     

旋风管不同排尘结构内流场及颗粒浓度场分析

采用智能型五孔球探针测试技术及等动采样方法，对两种新型旋风管排尘结构内的流场及颗粒浓度场进行测量。通过大量实验，发现在双锥内部存在的二次流及涡流使得颗粒分布呈现横向返混状态，这不利于颗粒的分离，对单锥与双锥两种不同排尘结构内的流场及颗粒浓度场分布特点进行了对比研究，为进一步优化旋风管排尘结构，提高分离性能奠定了实验基础。     

非定常流弯肘型尾水管不规则压力脉动预测

尾水管内螺旋状涡带引起的压力脉动是造成混流式水轮机机组振动的主要原因之一,直接威胁机组的安全运行。为此,提出一种基于CFD数值计算的水轮机尾水管压力脉动数字化预测法,并利用此法对一大型混流式水轮机偏工况下尾水管内水流流动进行了长时间非定常流计算,讨论该工况下尾水管内死水域与涡带的运动规律,预测了尾水管的不规则压力脉动,压力脉动分析结果表明,其波形、频率、相位与实际基本一致。     

双进双出钢球磨煤机的特性与故障处理

介绍双进双出钢球磨煤机双进双出、料位控制、辅助风系统和蒸汽惰性置换系统的特点，重点分析小齿轮断齿、大小齿轮齿面磨损点蚀严重、螺旋输煤绞笼损坏、磨煤机大瓦温度高、料位系统异常等常见故障及发生的原因，并提出相应设备和系统的改进措施。