高通量管换热器制造过程中的质量控制

简述了换热器的应用领域及适用范围,特别指出高通量管换热器的应用领域及发展现状,对高通量管换热器的主要质量控制环节进行总结.对高通量管换热器中的核心材料进行介绍.高通量管的制造及质量控制进行简述,介绍了高通量管的分类、技术特点、质量控制.介绍了高通量管换热器的制造及质量控制过程,通过对高通量换热器的制造经验及主要制造关键...     

换热器管子和管板焊接接头浅见

通过对管板换热器设计参数、介质特性、使用环境以及承载情况的分析研究,比较不同焊缝接头形式以及焊接工艺过程的选择对最终焊接质量的影响,同时阐述了合理的焊缝检验工艺对于确保在焊接前、焊接过程中以及焊接完成之后保证焊接质量的重要意义,总结出管板换热器管子和管板焊接接头在制造过程中的关键控制点。     

管壳式换热器管子与管板的贴胀

对管壳式换热器管子与管板的贴胀工艺进行了分析。通过试验的方法取得了贴胀胀管率的有效数据,确定了管子与管板贴胀时应该使用的胀管率。     

连接方式对换热器管子—管板接头可靠性影响

介绍了设备的工况、材料和制造工艺.分析了干燥再沸器、卧式再沸器管子-管板接头的失效 原因。对换热管管端外表面进行严格清理并采取液压胀管工艺,有效保证了换热器管子-管板接头的 制造质量。     

换热器管子管板胀接方法及质量控制

介绍了换热器管子管板胀接的多种方法、基本原理并进行比较、分析。提出了在胀接前、胀接中与胀接后各环节有效控制质量的若干要点。     

爆炸胀管技术在厚管板换热器管板与管子连接上的应用

介绍换热器爆炸胀管的试验过程,结果及其应用。     

换热器管子-管板焊接现状和改进方法

概述了国内换热器管子管板焊接的一般现状,由于其焊接的局限性和特殊性,焊接质量参差不齐.从前期坡口设计到焊接和检验过程提出了改进方法,主要是要选用易于焊透的坡口型式和尺寸,焊前进行模拟工艺试验及焊工考核.采用高性能设备的自动焊对焊接工艺进行升级,重视焊前及焊接过程的细节控制,加强焊缝的检验等,共同保证管子管板焊接工艺条件...     

热拉伸对PGLA(90/10)纤维降解性能的影响

利用热拉伸获得不同性能与结构形态的PGLA(GA/LA摩尔比=90/10)纤维,并进行体外降解实验。在降解过程中,采用DSC、傅里叶红外光谱、扫描电镜等测试手段对PGLA(90/10)纤维的性能与形态变化进行研究。结果表明,热拉伸显著改变PGLA(90/10)纤维的降解特征。     

换热器检修过程中换热管查漏方法新技术

石油化工行业对各类换热器的应用非常广泛。在使用过程中泄露问题时有发生,处理泄漏方法很多,也很成熟,但是,查漏工作始终困扰着业内人士。目前各企业均是在工装设计上投入了大量的精力,虽然取得了一定的效果,但都不够理想。因为均未摆脱繁重的体力劳动和笨重的工装卡具。通过反复实践和论证,确定利用单管抽真空代替水压试验对换热管查漏技术具备可行性;该施工方法通过了2007-2008年度的石油工法评审(省部级),题目为;利用抽真空的方法代替水压试验。并申请取得了持有专利技术的专用工具(换热器查漏用真空枪——专利号200810228742)。     

高通量管换热器在乙苯装置中的应用

以高通量管换热器在乙苯装置中的应用为例,进行了传质、传热过程的参数对比与工艺设计优化,通过高通量管换热器与普通管壳式换热器在传热效率、节能降耗、投资占地等方面的综合对比,证明了高通量管换热器具有明显应用优势,能够达到提升能效、节能降碳和增强乙苯装置竞争力的效果。     

(SrZrO3)10(SrTiO3)90缓冲层对PZT结晶及性能的影响

采用Sol-gel法制备了PbZr0.52Ti0.48O3 (PZT)薄膜,并研究了(SrZrO3)10(SrTiO3)90((SZO)10(STO)90)缓冲层对PZT薄膜结晶和性能的影响.X射线衍射(XRD)结果表明:(SZO)10(STO)90缓冲层对PZT薄膜结晶有取向诱导作用,由(SZO)10(STO)90诱导的PZT薄膜有很强的(111)择优取向,缓冲层将PZT薄膜的取向度α由45.0%提高到了90.1%以上;PZT的(111)择优取向提高了薄膜的电性能,使剩余极化强度Pr从26.8 μC/cm2增大到38.8 μC/cm2.     

Copolymerization of bis(chlorophthalimide)s with 2,5-dichlorobenzophenone catalyzed by NiBr2/PPh3/Zn

Copoly(phenylene-imide)s were synthesized by Ni(0)-catalyzed coupling of aromatic dichlorides containing imide structure and 2,5-dichlorobenzophenone. The route offered the flexibility of incorporating different ratios of benzophenone and imide groups in the polymer backbone in a controlled manner. The resulting copolymers exhibited high molecular weights (high inherent viscosity), and a combination of desirable properties such as good solubility in dipolar aprotic solvents and cresols, film-forming capability and good mechanical properties. Wide-angle X-ray diffractograms revealed that the polymers were amorphous. These copolymers had glass transition temperatures between 209 and 319 °C and 10% weight loss temperatures in the range of 502-543 °C in nitrogen atmosphere. The tough polymer films, obtained by casting from N-methylpyrrolidone solution, had a tensile strength range of 83-156 MPa and a tensile modulus range of 1.6-3.6 GPa.     

脂肪醇制备叔胺的新型催化剂的最新进展

对采用脂肪醇和二甲胺一步胺化制备(得率100%)相应的叔胺(烷基二甲基叔胺)的新型催化剂的最新进展进行了论述,对高活性Cu/Ni/Ca/Ba-St胶体催化剂(Cu0/Ni0/Ca0的比为5∶1∶1)和不含镍的Cu/La2O3进行了讨论。由此得出结论:要达到定量制备的关键因素是,通过结合还原钙或更活泼的促进剂,如Ce0和La0,尽可能地增加催化体系的氢解活性,由此形成金属氢化物,在铜/镍的作用下产生活性氢的“自供体系”。这一就地形成金属氢化物的基本功能将可极大地减少催化剂的用量,使铜质量分数减少到2×10-3%,从而极大地降低二甲胺的歧化,增加目的叔胺的选择性。总的来说,观察到在铜/镍固体催化剂以及胶体催化剂作用下,活性氢自供体系的基本功能使充入的大量氢一点都不被消耗掉。     

对氯苯乙酮单缩二氨基硫脲Ti(Ⅳ)、Ni(Ⅱ)、Cu(Ⅰ)配合物的直接电化学合成

在以对氯苯乙酮单缩二氨基硫脲 ( HL)为配体的非水溶剂中 ,用 Ti、Ni、Cu金属做阳极 ,用电化学金属阳极氧化法合成了对氯苯乙酮单缩二氨基硫脲与 Ti( )、Ni( )、Cu( )的金属配合物。通过元素分析、红外光谱、紫外光谱、磁化率、摩尔电导等对配体和配合物进行了表征。     

苯甲醛单缩二氨基硫脲Ti(Ⅳ)、Ni(Ⅱ)、Cu(Ⅱ) 配合物的直接电化学合成

在以苯甲醛单缩二氨基硫脲(HL)为配体的非水溶剂中,用Ti、Ni、Cu金属做阳极,用电化学金属阳极氧化法合成了苯甲醛单缩二氨基硫脲与Ti( )、Ni( )、Cu( )的金属配合物。通过元素分析、红外光谱、紫外光谱、磁化率、摩尔电导等对配体和配合物进行了表征。     

Electrochemistry of non-aged 90-10 copper-nickel alloy (UNS C70610) as a function of fluid flow: Part 2: Cyclic voltammetry and characterisation of the corrosion mechanism

The cyclic voltammetry and mixed potential behaviour of freshly polished UNS C70610 (CN 102) 90-10 copper-nickel has been examined in fully characterised seawaters using the rotating disc electrode (RDE) and the rotating cylinder electrode (RCE). Reynolds number dependent corrosion potentials are derived for a wide range of Reynolds numbers and good comparison is made with directly measured values. The films formed on initial exposure of the 90-10 copper-nickel alloy to the seawaters did not confer any additional protection relative to unalloyed copper. Indeed, the 90-10 copper-nickel tended to exhibit relatively high anodic and cathodic currents when directly compared to both unalloyed copper and a nickel aluminium bronze under identical conditions. The corrosion potential of the alloy becomes more negative at higher flow velocity, due to the influence of mass transport on the anodic reaction mechanism at potentials close to the mixed potential. Overall, the results indicate that the character of the freshly polished material/electrolyte interface has a much greater influence over the magnitude of the corrosion rate than the turbulence intensity of the fluid.     

Effect of nickel coating on carbon for adsorption of cadmium from aqueous solutions

Nickel was coated on carbon and it was characterized by SEM and XRD. Sorption of Cd(II) ions onto carbon and nickel‐coated carbon (Ni/C), effect of acids, pH, shaking time, loading capacity, and adsorbent weight has been investigated. Acids reduce sorption and maximum sorption takes place from deionized water and R_d values for carbon and Ni/C in deionized water are 212.9 ± 0.9 and 232.5 ± 2.5. The sorption data followed the Freundlich, Dubinin–Radushkevich (D–R), isotherms and different parameters have been calculated. Sorption free energy values have been calculated and are 12.56 ± 0.19 and 14.84 ± 0.196 for carbon and Ni/C and indicate that adsorption process is chemisorption. Increase in adsorption shows the increase in catalytic activity of the adsorbent. The variation of sorption with temperature has been used to calculate the values of ΔH, ΔS, and ΔG for Cd(II) sorption. These values show that adsorption of Cd(II) ions on the adsorbents is endothermic, spontaneous, and entropy driven. Coating of carbon with nickel has improved its adsorption properties. Adsorption behaviour provides useful information for the catalytic activity of catalysts.     

Nickel and copper removal study from aqueous solution using new cationic poly[acrylamide/N,N‐DAMB/N,N‐DAPB] super absorbent hydrogel

A new cationic poly[acrylamide/N,N‐diallyl morpholinium bromide/N,N‐diallyl piperidinium bromide] super absorbent hydrogels (H1–H7) were prepared via microwave irradiated free radical cyclopolymerization using different composition. By the swelling study, hydrogel H1 is found to bear good swelling properties amongst all prepared hydrogels. The hydrogel H1 has been characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), and TGA analysis. A batch system was applied to study the adsorption of Ni(II) and Cu(II) from aqueous solutions by hydrogel H1. The effect of treatment time, pH of the medium, amount of adsorbent doses, and initial feed concentration of metal ion on adsorption of Ni(II) and Cu(II) from their solution were also investigated. Adsorption of Ni(II) and Cu(II) increases with the increase in treatment time, adsorbent doses, and initial feed concentration and decreases with the increase in pH of the medium. The desorption of metal ions were carried out using 1N HCl and 0.5N H₂SO_4. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

两种新型镍-邻菲咯啉类核酸荧光探针的合成及性质研究

合成了咪唑并[f]邻菲咯啉(IP)和对羟基苯基咪唑并[f]邻菲咯啉(PHPIP)两种配体，并合成了两种新配合物Ni(Phen)2PHPIP和Ni(Phen)2IP，对其进行了表征，用紫外光谱、静态荧光光谱研究了配合物与小牛胸腺DNA的结合情况。两种配合物均与DNA有强烈作用，其中配合物Ni(Phen)2PHPIP在水溶液中几乎无荧光，而加入DNA后，能发射出很强的荧光，可以作为检测核酸分子的荧光探针。     

Electrochemistry of non-aged 90-10 copper-nickel alloy (UNS C70610) as a function of fluid flow: Part 1: Cathodic and anodic characteristics

The polarisation behaviour of freshly polished UNS C70610 (CN 102) 90-10 copper-nickel has been examined in fully characterised seawaters using the rotating disc electrode (RDE) and the rotating cylinder electrode (RCE) geometries. The charge and mass transport controlled responses of both the cathodic and anodic reactions are presented as a function of both laminar and turbulent undisturbed fluid flow. At low values of polarisation applied over short exposure periods (<1 h), the anodic behaviour of non-aged material is controlled by the selective dissolution of the copper component of the alloy. Under conditions of complete mass transport control, oxygen reduction proceeds via the irreversible direct four-electron reduction to the hydroxide ion. Above a critical range of Reynolds numbers the rate of both the reduction and oxidation reactions tended towards a more reversible character. This change in mechanism, however, was not observed for unalloyed copper and was attributed to a convective-diffusion-based modification of the corrosion product film.