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51.
复电阻率测井是以两频或多频测量地层电阻率的新方法 ,它可用来有效地识别油气层和确定水淹油层的水淹程度。简要介绍了复电阻率测井的测量原理、仪器设计。胜利油田 9口井的现场测井资料初步验证了该方法的可行性和有效性  相似文献   
52.
对风动工具及用油情况进行了论述,根据风动工具用油特点和使用环境要求,选用大庆原油生产的HV1650组分油为基础油,加入抗氧抗腐剂(T203),剂量为0.50%;加入剂量为0.07%的防锈剂(T705),试验结果为无锈。进行添加剂配方优化,油品各项性能均满足指标要求,并通过了使用试验。  相似文献   
53.
The forces, chip thickness, and natural tool–chip contact length in machining with a double-rake-angled tool are predicted in Part II of the present study. It is revealed that in comparison with a single-rake-angled tool, a double-rake-angled tool increases the forces, especially the thrust force. However, the increase in chip thickness and tool–chip contact length is not significant under the input conditions specified in the present study. The effect of seven input variables of the proposed model is quantitatively investigated. The predicted variations of forces, chip thickness, and natural tool–chip contact length are in good agreement with theoretical and experimental results obtained by other researchers. The interrelationships among the resultant force, the chip thickness, and the natural tool–chip contact length are established, which provides a new and promising method to estimate the tool–chip contact length by employing the resultant force. It is demonstrated that the model can also be extended to study the problem of machining with a groove-type chip breaker tool.  相似文献   
54.
Linear elastic fracture mechanics was used to optimize the vacuum heat-treatment procedures for conventional hot-work AISI H11 tool steel. The fracture toughness was determined with non-standard, circumferentially notched and fatigue-precracked tensile-test specimens. The fracture-testing method is sensitive to changes caused by variations in the microstructure resulting from the austenitizing and tempering temperatures as well as the homogeneity of the material itself. The combined tempering diagram- Rockwell-C hardness, Fracture toughness KIc, Tempering temperature was used for the choice of the vacuum heat-treatment parameters necessary to obtain the best properties for a given application with respect to the investigated steel.  相似文献   
55.
水力脉冲式钻井工具的研制与应用   总被引:2,自引:1,他引:1  
水力脉冲式钻井是利用特定的工具使钻井管柱中的连续流转变为脉冲射流,从而改变井底流场的压力状况,进而提高机械钻速的一种钻井新工艺。在分析水力脉冲产生机理的基础上,探讨了基于瞬变流理论的机械阻断式水力脉冲破岩机理,介绍了SLPMC机械阻断式水力脉冲工具的工作原理及结构特点,简单叙述了该工具在胜利油田进行的2口井的现场试验情况。该钻井工具对于提高机械钻速和降低钻井成本具有一定的积极意义。  相似文献   
56.
本文提出基于切削振动相关性识别刀具磨损状态的研究思想,建立了车削中刀杆双向横振动系统及其单输入双输出系统的数学模型。理论和实验均表明,刀杆双向横振动之加速度响应在固有基频处的相干函数与刀具磨损状态之间有很好的规律性,它反映了两者之间的本质机理,并提供了识别刀具磨损状态的新途径。  相似文献   
57.
58.
The growth of carbide particles in TiC-XC-2 vol.% Ni and TiC-XC-30 vol.% Ni alloys, where X=Zr, Cr, W, Ta and Mo, was fitted to an equation of the form d3-do 3=Kt. The grain growth behavior during liquid phase sintering at 1673K decreased markedly with the addition of Mo2C or WC, changed little for TaC, and increased with the addition of ZrC or Cr3C2. The grain contiguity decreased with increasing Ni content in the TiC−Mo2C−Ni alloy and was greater in the alloys with smaller growth rate constant. Consequently, the effect of carbide addition on the grain growth of 2 vol.% Ni alloys was found to be similar to that of 30 vol.% Ni alloys. The grain growth mechanism could be explained by the effect of contiguous carbide grain boundaries in restricting the overall grain growth, as well as the area of the solid/liquid interfaces in the alloy by the usual solution/reprecipitation model.  相似文献   
59.
利用Glejser检验方法拟舍出刀具磨损过程残差模型,在此基础上,计算换刀时刻的过程能力指数,并且根据企业所要求的最低过程能力指数,计算刀具的质量寿命,提出将刀具的切削寿命和质量寿命结合起来进行换刀决策的方法。  相似文献   
60.
A model for building integrated photovoltaic systems has been developed and implemented in a dynamic simulation tool. This tool takes into account the thermal interactions between the PV collector and the building. The influence of the type of integration upon the PV collector efficiency has been evaluated and hybrid PV/air collectors have been studied. An overall efficiency is defined, including the production of electricity and heat. A case study has been performed on two different typical buildings. In the case of a multi-crystalline silicon PV collector integrated on the roof of a single family house located in Paris, the efficiency of unventilated PV modules fixed on the roof is 14%. If the PV collector is used to preheat the ventilation air, the efficiency reaches 20%. A proper building integration also improves the environmental balance of PV technologies over their life cycle.  相似文献   
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