《ISO 13679:石油天然气工业 套管及油管螺纹连接试验程序》的仿真方法

依照《ISO 13679:石油天然气工业套管及油管螺纹连接试验程序》进行实物试验并据此评价油管和套管特殊扣的性能,不仅耗时长而且成本高昂。为此,以?73.0 mm×5.51 mm J55钢级中低压力、中高温度的经济型气密封特殊扣为例,基于ABAQUS软件,通过建立有限元模型,在考虑仿真分析过程中的几何非线性、材料非线性和边界条件非线性耦合问题的基础上,依据弹塑性的双线性等向强化模型和超弹性Moony-Rivlin模型的材料本构关系,对上扣工况和ISO 13679的Ⅱ级试验B系载荷包络线工况进行了仿真评价,计算得到了各个工况下特殊扣的接触位移、最大接触压力、密封积分强度、等效应力等重要参数,其计算结果与实物密封试验结果的误差小于7.3%,对于密封性能的有限元分析结果与实验结果一致,进而利用上述参数评价了特殊扣在各工况下的结构与密封性能。结论认为,按照ISO 13679的试验内容和程序所建立的仿真评价方法,能够高效地对气密封特殊扣的性能进行评价,可以极大地节约时间成本与经济成本,能在一定程度上代替特殊扣的实物评价。     

峰岛D25 Premium薄刃剪钳测评

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考虑赠品促销影响的供应链协调模型研究

在考虑赠品促销对市场需求具有影响效应的前提下,构建了市场需求预测与赠品相关的供应链协调模型,证明了该模型能使供应链渠道得到有效协调;并建立了这类契约的最优决策模型,得出最优解存在的条件以及最优解的表达式;然后分析了模型中相关参数的变化对最优决策变量及供应链利润的影响。     

弯曲载荷下特殊螺纹接头密封性能的有限元分析

借助Abaqus软件建立了特殊螺纹接头弯曲性能分析有限元模型,并对某个规格特殊螺纹接头进行了纯弯曲的有限元分析。结果表明:随着弯矩的增加,拉伸面接触应力下降,接触长度减小,密封性能下降;而压缩面接触应力上升,接触长度增加,密封性能提高。这些结果说明提高特殊螺纹接头的弯曲性能需要同时提高接头的拉伸与压缩性能。     

优质重庆高山贡米筛选及其理化成分与食味特性关系研究

本实验以重庆高山贡米为研究对象,探究了重庆高山贡米食味值及其理化成分与食味特性关系.通过收集31种不同产地的重庆高山贡米,分析评价其外观品质、营养品质、氨基酸及食味值,并对成分与食味值进行关联分析.结果表明:31种重庆高山贡米在外观品质、营养品质、氨基酸及食味值之间均存在显著性差异(P＜0.05),其中孙家贡米为综合评...     

石油套管用特殊螺纹接头数控加工方法研究

特殊螺纹接头具有较高的连接强度和良好的密封性能,在石油套管中的使用越来越多。提出一种新型特殊螺纹接头,通过分析其螺纹结构及现有加工条件,提出采用数控车床通过两次螺纹车削循环指令加工该特殊螺纹的方法,并基于FANUC数控系统进行了编程举例。     

我国特殊螺纹接头油套管生产使用现状及需要注意的几个问题

随着钻井技术的进步,油套管的服役条件更加苛刻,按照API标准生产的油套管螺纹接头已经不能满足某些油气井的使用要求,因此特殊螺纹接头的应用范围不断扩大。我国开发特殊螺纹接头尚处于初级阶段。综述了我国特殊螺纹接头油套管的生产使用现状,指出了我国特殊螺纹接头使用和开发过程中需要解决的问题,并就特殊螺纹接头的开发提出了几点建议。     

复杂工况油套管柱失效控制与完整性技术研究进展及展望

随着对深层碳酸盐岩、新区、页岩等油气勘探开发力度的加大,油气田的地层条件和介质环境变得更为苛刻复杂,油套管柱变形、泄漏、腐蚀、挤毁、破裂等失效事故时有发生;加上特殊结构井和特殊工艺井、特殊增产改造措施等对油套管柱提出的新要求,油套管柱面临着一系列新的挑战和难题需要破解。为此,围绕我国石油天然气工业增储上产的迫切需求和深井超深井、特殊结构和特殊工艺井、强酸/大排量高压力反复酸化压裂增产改造等复杂工况油套管柱失效频发的技术难题,历经十余年攻关,取得了一系列试验研究进展与重要技术成果,主要包括:(1)形成了基于气井全生命周期的油套管腐蚀选材评价、腐蚀控制和油套管柱完整性技术;(2)形成了油套管柱螺纹连接结构和密封可靠性设计评价及配套技术;(3)研发并形成了低渗透致密气井经济高效开发“API长圆螺纹套管+CATTS101高级螺纹密封脂”套管柱技术;(4)建立了高温高压等复杂工况油套管柱结构和密封完整性试验平台和评价技术。进而根据当前国家大力提升油气勘探开发力度的新要求和面临的新问题,提出了继续深入开展深层、酸性环境、页岩气等复杂工况油套管柱失效控制与完整性研究攻关的若干建议。结论认为,上述技术成果有力地支撑了我国重点油气田的经济有效开发。     

Searching for the sound of premium beer

One common definition of premiumness is as a higher quality and more expensive variant of a product than other members of the category or reference class. Premiumness can effectively be conveyed by means of different sensory cues (e.g., colours, sounds, weight). However, to date, research linking the sound of a product’s packaging with premiumness is sparse. In the present study, we demonstrate for the first time that consumers associate different levels of beer premiumness with the sounds of opening and pouring of bottles and cans. We report the results of two online experiments. Experiment 1 explored the effect of two sound properties associated with beer can and bottle opening and pouring (sound pressure and frequency) on the perception of premiumness. Experiment 2 used semantic differential scales (e.g., bad-good, passive-active) to evaluate the meanings people tend to associate with different auditory cues. The analyses revealed that participants perceived: 1) bottle sounds to be more premium overall than can sounds, 2) pouring sounds as more premium than opening sounds, and 3) higher pressure sounds as more premium than lower pressure sounds. Additionally, premiumness was positively correlated with semantic differentials of dead-alive, and the evaluative terms of sad-happy, awful-nice, and bad-good, which highlights the perceived quality and premium character of a beer when conveyed auditorily.     

An Adaptive Large Neighborhood Search for an E-grocery Delivery Routing Problem

Online shopping has become ever more indispensable to many people with busy schedules who have a growing need for services ranging for a wide variety of goods, which include standard (or “staple”) goods as well as “premium” goods, i.e. goods such as organic food, specialty gifts, etc. that offer higher value to consumers and higher profit margins to retailers. In this paper, we introduce a new mathematical programming formulation and present an efficient solution approach for planning the delivery services of online groceries to fulfill this diverse consumer demand without incurring additional inventory costs. We refer to our proposed model as the E-grocery Delivery Routing Problem (EDRP) as it generically represents a family of problems that an online grocery is likely to face. The EDRP is based on a distribution network where premium goods are acquired from a set of external vendors at multiple locations in the supply network and delivered to customers in a single visit. To solve this problem, we develop an improved Adaptive Large Neighborhood Search (ALNS) heuristic by introducing new removal, insertion, and vendor selection/allocation mechanisms. We validate the performance of the proposed ALNS heuristic through an extensive computational study using both the well-known Vehicle Routing Problem with Time Windows instances of Solomon and a set of new benchmark instances generated for the EDRP. The results suggest that the proposed solution methodology is effective in obtaining high quality solutions fast.