Simulation of Natural Depletion and Miscible Gas Injection Effects on Asphaltene Stability in Petroleum Reservoir Fluids

Natural depletion of petroleum reservoirs as well as gas injection for enhance oil recovery, are unavoidable processes in the oil industry. Foremost, prediction of the problems due to these two processes is very necessary and important. So many field and experimental experiences have shown that heavy organic depositions, especially asphaltene deposition, are principal results during these processes. Results of laboratory simulation of asphaltene deposition during the natural depletion of petroleum reservoirs and also during gas injection and enhanced oil recovery (EOR) processes are reported here. This is achieved through the design of a new experimental setup for the investigation of pressure and composition effects on asphaltene deposition in petroleum fluids at high pressure and high temperature conditions. In this work, asphaltene deposition during decreasing pressure, from pressures greater than reservoir pressure to pressures below the bubble point pressure (natural depletion) and also asphaltene deposition during natural gas injection in reservoir conditions, are studied for three samples—one recombined sample and two bottomhole samples. All of the obtained results from this work conform to theoretical and other experimental works.     

莱钢冷轧轧机弯辊控制系统分析

对莱钢冷轧六辊单机架的弯辊系统进行研究与分析,介绍板形控制系统的原理和使用效果。     

智能力敏传感器的研制

针对传统的差压密度计和压力式液位计分别存在可靠性不高、不适用于介质密度经常变化的场合的问题,设计了一种基于Freescale MC9S08AW60微控制器的智能力敏传感器,详细介绍了该传感器主要电路的设计。该智能传感器实现了数据采集、信号处理、数据通信和电流环输出式数模转换功能。实际应用表明,在-20～+80℃的工作温度范围内,密度测量精度可达±5kg/m3,液位测量不受悬浮液回流和液位波动的影响,很好地满足了工业现场的应用。     

温度对Ni—P化学镀层结合力影响的研究

用弯曲法、划痕法研究了镀后加热温度对Ni-P化学镀层结合力的影响,结果表明:镀后退火温度越高,镀层结合力越好,但温度过高时,镀层硬度将下降。用金相观察及电子探针分析,探讨了镀后退火温度影响结合力的机理。结果指出:退火时将在镀层和基体界面上发生Ni与Fe的互扩散,形成Ni-Fe合金扩散层,从而提高了结合力。为了能在保证镀层硬度的前提下提高结合力,本文提出了二次镀覆的设想,获得较好试验结果。     

离子氮化对镀铬层组织与性能的影响

研究了镀铬层经离子氮化后的组织和性能。分别用SEM、电子探针和X光衍射仪观察和分析了复合处理层剖面的组织、结构和成分,试验结果表明:离子氮化能使镀铬层的网状裂纹弥合,可明显提高了镀层表面硬度、结合力和耐蚀性。     

不同添加剂对AgSnO2In2O3触头材料电性能的影响

采用内氧化法工艺制备了不含添加剂及分别含添加剂CuO或TeO2的3种AgSnO2In2O3触头材料。应用模拟继电器试验设备检测了这3种材料在AC230 V、25 A阻性负载条件下的电寿命、熔焊力、电弧能量、燃弧时间、质量侵蚀率等相关电性能参数,并对检测结果及试验后铆钉触头样品进行了分析。研究发现:与不含添加剂的AgSnO2In2O3材料相比,添加剂CuO对材料的电寿命影响不大,而添加剂TeO2明显提高了材料的电寿命;含添加剂的两种材料的熔焊力和电弧能量均有了不同程度的降低,但它们的质量侵蚀率却明显增加。     

水泥散装无人值守系统数据管理

数据的实时性、准确性、全面性和灵活性是水泥散装无人值守高效、稳定、可靠运行的保证。本文主要以某水泥集团散装技改为例,讨论散装无人值守系统中运用的技术手段和对数据的管理。     

划痕法测Ni—P合金镀层结合力的研究

本文用划痕法测定了Ni-P合金镀层的结合力;观察了划痕侧面镀层的失效形式;分析了三种评定结合力的参数。结果指出,临界载荷L_C、平均应力σ_A用于评定Ni-P镀层的结合力是有条件的,而B-W公式存在的问题更多。     

Cutting force estimation in sculptured surface milling

Cutting force milling models developed up to now are mostly used for planar milling using end-mills. Only a reduced number of models applying ball-end mills have been developed. Furthermore these models usually only consider horizontal surface machining, even though the main application of ball-end mills is sculptured surface machining. This article proposes a model that is able to estimate the cutting forces in inclined surfaces machined both up-milling and down-milling. For this purpose a semi-mechanistic model has been developed that calculates the cutting forces based on a set of coefficients which depend on the material, the tool, the cutting conditions, the machining direction and the slope of the surface.A coordinate transformation has been included in order to consider the slope milling case with different cutting directions.The model has been tested on two materials, an aluminum alloy Al7075-T6 and a 52 HRC tool steel AISI H13. Validation tests have been carried out on inclined planes using different slopes and different machining directions.The results provide errors below 10% in most of the cases and both the value and shape of the predicted forces adjust the measured cutting force.