碳钢管路在某型艇舱底水中的腐蚀原因分析

目的调查20号碳钢在海水和舱内污水中的腐蚀原因。方法采用全浸腐蚀试验、电偶腐蚀测试、电化学测试和腐蚀形貌分析等方法对某型艇碳钢海水管路的腐蚀原因进行研究。结果获得了20号碳钢在海水和舱内污水中的腐蚀速率、腐蚀电位、极化曲线、阻抗图谱、腐蚀形貌等数据。结论舱底碳钢管的腐蚀主要是由于管内海水的腐蚀、焊接对管材的热影响和舱内污水的腐蚀作用引起的,其中管内海水的腐蚀作用是主要因素。     

Study of mechanical aspects of leak tightness in a pressure relief valve using advanced FE-analysis

This paper presents a numerical study involving the deformation of contact faces in the metal-to-metal seal in a typical pressure relief valve. The valve geometry is simplified to an axisymmetric problem, which comprises a simple geometry consisting of only 3 components. A cylindrical nozzle, which has a valve seat on top, contacts with a disk, which is preloaded by a compressed linear spring. All the components are made of AISI type 316N(L) steel defined using the multilinear kinematic hardening model based on monotonic and cyclic tests at 20° C. In-service observations show that there is a limited fluid leakage through the valve seat at operational pressures about 90% of the set pressure, which is caused by the fluid penetrating into surface asperities at the microscale. Nonlinear FEA in ANSYS using the fluid pressure penetration (FPP) technique revealed that there is a limited amount of fluid penetrating into gap, which is caused by the plastic deformation of the valve seat at the macroscale. Prediction of the fluid pressure distribution over the valve seat just before the valve lift is addressed in this study considering the FPP interaction on multiscale. This is the principal scope, since it allows adjustment of the valve spring force in order to improve the leak tightness.     

Printed in great Britain Cr(VI) and other metallic mutagens in fly ash and welding fumes†

Particulate samples taken from both the indoor (working) and outdoor (community) environments contain a wide range of metallic trace elements most of which are mutagenic in at least one of the short term tests for genotoxicity currently in use. Because of the demonstrated presence of a short lived biologically active species (Cr(VI)), and the uncertainty with which the results of the screening of metallic compounds in short term tests can be interpreted in terms of human risk, great care must be taken to assure the appropriate collection, storage, and chemical and biological assay of such material. The sensitivity of the results for fly ash and welding fumes to variations in these protocols is demonstrated and discussed.     

两起钢丝绳芯输送带断裂事故的分析及对策

通过两起钢绳芯胶带断裂事故的分析,提出了具体和有效的对策措施。     

钢线拉丝及表面处理生产线成套装备

主要论述了一种钢线拉丝及表面处理生产线成套装备的设计。该生产线的生产方式是多根钢线在牵引动力系统的作用下依次穿过各种处理设备,完成各道工序,实现钢线完成表面处理的目的。这个生产过程中,钢线可以完成放线、脱脂、退火、镀镍、造膜、烘干及收线一体化的工序。采用立体式布置,空间利用更为合理。     

Effective removal of phosphorus from high phosphorus steel slag using carbonized rice husk

High phosphorus steel slag and carbonized rice husk are two common wastes characterized by high generation and low secondary use values.Through the reduction of high phosphorus steel slag by biomass,both wastes were fully utilized,thus reducing the negative impact on the environment.In this study,variables such as temperature,time,and amount of reactants were changed to determine the optimal conditions for the reaction of steel slag with carbonized rice husk at high temperatures.The actual amoun...     

基于层次模糊综合评价的安全标准化成熟度评价

为了实现对轧钢企业安全生产标准化体系的系统性分析与评估,并为企业的安全标准化体系提供一条分级提升的路径,基于过程改进的原理,将安全标准化体系发展水平分为5个等级,构建安全标准化体系成熟度模型。对轧钢企业安全标准化评分标准进行整合,建立评价指标体系、确定指标权重。通过调查问卷确定成熟度的隶属度,根据单因素评价指标结果绘制柱状图,分析影响轧钢企业安全标准化成熟度的主要因素。采用层次模糊综合评价法,量化评估企业安全标准化成熟度。结果表明,该模型的评价结论与该企业实际情况吻合度较高。     

河北邯郸钢铁冶炼区周边麦田土和小麦籽粒的多环芳烃含量及其组分谱特征

在大型邯郸钢铁公司周边不同样区的麦田成对采集表层土壤和成熟的小麦籽粒样品,检测US EPA优控的16种母体多环芳烃(polycyclic aromatic hydrocarbons,PAHs)的浓度和组分谱,确定当地麦田表土PAHs的空间分布特征、与总有机碳TOC分数的相关性.由此,初步开展PAHs源解析,并简单探讨小麦籽粒PAHs与表土PAHs的关联性.结果表明,麦田表土总PAHs平均中位数含量为398.9 ng·g-1(范围123.4~1 626.4 ng·g-1),根据丹麦的土壤质量标准,所有表土样品中PAHs总含量超过限值占18%,而苯并[a]芘含量超过限值的样品占总数的10%.表土PAHs组分谱以中、高环组分为主体.利用同分异构体特征比值进行初步源解析,显示煤与生物质燃烧和交通燃油(尾气)是当地PAHs主要混合排放源.各样区麦田表土TOC分数与PAHs总含量、与不同环数组分含量都呈现类似的显著正相关.邯郸钢铁公司周边麦田小麦籽粒的总PAHs平均中位数含量为27.0 ng·g-1(范围19.0~34.0 ng·g-1),PAHs含量较低且未超过欧盟与国内的相关食品卫生标准.小麦籽粒中优势低环组分占总体的84%,其组分谱分布与麦田表土有所不同,显示小麦籽粒的PAHs除去根部吸收、传输外,还存在大气干湿沉降通过叶表(气孔)进入小麦体内等其它输入途径.     

浮码头钢趸船防腐涂装体系研究

目的为浮码头钢趸船优选防腐涂装体系,以延长其使用寿命。方法根据钢趸船腐蚀环境特点,对选用的防腐涂料进行对比试验,针对不同的腐蚀环境,优选不同的防腐蚀方案。结果制定了4套与不同腐蚀环境相对应的防腐涂装体系。结论该防腐蚀涂装体系已在上海、青岛、湛江等海域的钢趸船上使用,效果良好。     

Inertia welding for assembly of copper squirrel cages for electric motors

The automotive industry is developing designs and manufacturing processes for new generations of electric motors intended for use in hybrid and electric vehicles. There is interest in replacing the aluminum traditionally used in induction motor rotors with copper to improve motor capability. This paper focuses on solid-state welding to join copper end rings to copper spokes in the fabrication of copper rotors. Inertia friction welding was explored to examine weldability of these copper components. A better understanding of inertia welding characteristics will help the advancements in its application for induction rotors. The limitations of this application are discussed.