筒体端部大直径内螺纹的数控铣削

本文结合氨合成塔的制造，利用先进的数控机床及螺纹铣刀，通过工艺实验解决简体端部内螺纹直径大、质量要求高等制造技术难点，并成功应用在产品制造中。     

氨合成塔外壳制造技术

介绍了氨合成塔外壳的主要制造过程,重点阐述了筒体成形、锻件机加等工艺方案。     

乙二醇合成塔制造难点技术研究

本文介绍了乙二醇合成塔的制造工艺难点,简述了乙二醇合成塔的制造工艺流程,重点阐述了制造过程中遇到的技术难点和质量控制措施,为此类大直径列管式换热器的生产提供一些有益经验。     

氧化液冷却器的质量控制

氧化液冷却器是国家级新产品,该设备材料、工艺复杂,技术质量要求高,针对上述问题,详述了氧化液冷却器的设计、制造、检验与验收,通过对关键事项的控制来保证产品的质量。     

氨合成塔出口气的制冷与节能

目前,小氮肥厂均采用传统的冷冻机压缩制冷方法,其电、油、维修费等消耗较高。利用合成塔出口气的低位热能,采用单级氨吸收制冷的途径取代冷冻机,即可达到节约能源,降低消耗之目的。单级氨吸收制冷是将供冷后的气氨转入浓氨水溶液,以合成塔出口气的潜热为动力,使其蒸发达到一定压力,继而冷凝为液氨,再供制冷之用。通过计算,小氮肥厂合成塔出口气体的热能,约为所配套冷冻系统压缩功的5～7倍。因此,利用塔出口气的热能制冷取代冷冻机压缩制冷是完全可行的。1 流程由氨冷器3蒸发的气氨与进氨冷器液氨在过冷器2换热后,进氨吸收器4,制成50%浓度     

钌基氨合成催化剂工业化应用的模拟与分析

上世纪90年代,KBR将新型钌基催化剂成功应用于氨合成工业生产,并且形成以钌基催化剂为核心的KAAP工艺。钌基催化剂由于其远高于铁基催化剂的活性特征,已经在提高产量、降低能耗方面显示出无可比拟的优越性能。钌基催化剂作为氨合成第二代催化剂,与铁基催化剂相比,具有活性高,使用寿命长,操作条件相对缓和等优点,国内已经开发成功,但未见工业化应用报道。针对某大型氨厂氨合成回路扩能改造,提出对现有3个合成塔中的第三塔进行改造,改造后第三塔装填钌基催化剂,催化剂床层由一个增加为两个,床层之间有换热器。应用模拟软件Aspen Plus对该方案进行模拟研究,并与现有改造方案进行对比分析。结果表明,本方案在不新增合成塔数量的前提下,即可实现提高液氨产能35%的目标;改造后的3个合成塔运行参数满足工业生产要求,钌基催化剂在较高氨含量下仍然表现出优异的活性;与现有新增合成塔的改造方案相比,本改造方案在成本方面具有较大的经济优势。     

热高分罐制造技术

随着石油化工业的飞速发展和国家对环境保护要求的提高。加氢装置的需求量越来越大，给化机装备企业带来了更大的发展机遇。国内制造加氢装置设备的厂家为数不多。针对加氢装置设备质量要求高、制造难度大、制造周期长的特点，某公司对其制造的蜡油加氢装置中的关键设备耐高温腐蚀材料制热高分罐，设备总高12m，设备工作温度较高，从原材料（包括焊接材料）、焊接工艺性试验、制造过程等主要环节进行质量控制。对保证产品质量和生产周期起到了至关重要的作用。     

浅议水工金属结构设备的采购控制

与传统的水利工程或水电工程相比,航电枢纽工程的金属结构设备(闸门、拦污栅、启闭机等)数量大、种类多、质量要求高、制造工期长。业主通过加强对水工金属结构设备的采购控制,达到确保水工金属结构设备的质量和制造工期的目的。     

锅炉制造生产中焊接质量控制和管理

焊接是锅炉制造生产中的一道关键工序,只有对其全过程进行严格的控制和管理,才能保证锅炉的制造质量,确保锅炉设备的安全可靠运行.     

由一起压缩机螺栓断裂事件引发的思考

某输气管线增压站国产压缩机气缸气阀盖螺栓突然发生断裂,导致厂房受损,大量可燃气体泄漏,究其原因,是螺栓强度偏低、加工工艺不当,且安装时未控制预紧力。该事件暴露出国产往复式压缩机组在引进技术消化吸收、原材料来源、加工制造过程质量控制及成本控制方面存在问题。大型往复式压缩机的国产化及其在石油天然气行业的广泛应用已是大势所趋。为提高国产化往复式压缩机组的整体质量,制造企业应加强质量管理,不仅重视工艺设计,更要重视设备的细节设计。必须结合国产材料性能及国内加工制造水平,制定完整的应对策略,设计和制造环节可适当增加安全系数。采购方应严格选择第三方机构进行设备检验,招标过程中适当加大设备技术水平的权重,避免一味追求低价,合理的价格是保证设备质量的关键条件。     

0Cr18Ni10Ti与（SA387Gr11c12＋堆焊层）异种钢的焊接工艺

针对产品加强管（0Ci118Ni10Ti）与筒体（SA387Gr11C12＋堆焊层）角焊缝异种钢焊接接头焊接问题，提出了先在筒体开孔厚度上焊接隔离层，然后再焊接角焊缝实践证明，采用这种焊接工艺进行焊接，可以获得优良的焊缝，能够保证设备的正常运行、     

Evaluation of the transgranular cracking phenomenon on the indian point no. 3 steam generator vessels

A metallurgical investigation was performed on specimens from the shell of steam generators Nos 31 and 32 of the Indian Point-3 power plant. The shell material exhibited high values in hardness which was indicative that relatively high residual stresses may have been present. All observed cracks were transgranular in appearance and were associated with pits on the vessels' inside surfaces. Both stress relieved and non-stress relieved specimens of SA302 Grade B material were tested in a constant extension rate apparatus in various environments in order to reproduce the transgranular cracking at Indian Point-3. The paper concludes that SA302 Grade B material is susceptible to transgranular stress corrosion cracking (SCC) in constant extension rate testing (CERT) with as little as 1 ppm chloride (as CuCl₂) in H₂O at 268°C.     

FREE VIBRATIONS OF A CONICAL SHELL WITH TEMPERATURE-DEPENDENT MATERIAL PROPERTIES

This article presents an analysis of the free vibrations of a truncated conical thin shell subjected to thermal gradients. The governing equations of the shell are based on the Donnell-Mushtari theory of thin shells. Simply supported and clamped boundary conditions are considered at both ends of truncated conical shell. Temperature loading due to supersonic flow is assumed to vary along the meridian and across the thickness of the shell Hamilton's principle is used to derive the appropriate governing equations of a conical shell with temperature-dependent material properties. The shell material has a kind of inhomogeneity due to the varying temperature load and temperature dependency of material properties. The resulting differential equations are solved numerically using the collocation method. The results are compared with certain earlier results. The influence of temperature load on the vibration characteristics is examined for the conical shells with various geometrical properties.     

Nanoparticle-based approach for the formation of CIS solar cells

In this study, nanoparticle-based approach was suggested for the formation of CuInSe₂ (CIS) layer. Nanoparticles with core–shell structure were used as the precursor material, and binary phases were used as core and shell material in the core–shell structure to maximize the kinetics of CIS formation reaction. From the investigation of the effect of heating rate on Se-loss, it was concluded that Se-loss could be minimized by using high heating rate and core–shell structure with a binary compound. By minimizing Se-loss before and during CIS formation reaction, it was shown that CIS layer could be formed without Se overpressure. CIS solar cell made in this study showed the highest efficiency of 1.11%, which showed a CIS layer for the device could be obtained without selenization process.     

Numerical study on melt fraction during melting of phase change material inside a sphere

This paper presents a numerical study on the constrained melting of phase change material (PCM) inside a sphere to investigate the effect of various factors on the melt fraction. A mathematical model of melting processes of the PCM inside a sphere is developed. And experiments are conducted to verify the numerical method. On the basis of the model, the effects of the sphere radius, the bath temperature, the PCM thermal conduction coefficient and the spherical shell material on the melt fraction of PCM inside a sphere are discussed. The results show that the PCM inside a sphere melts fast as the sphere radius is small, the bath temperature increases, and the PCM thermal conductivity is high. And the metal shell with high thermal conductivity should be adopted preferentially. The present study provides theoretical guidance for the design and operation of the phase change heat storage unit with sphere containers.     

THERMOELASTICITY OF A REGULARLY NONHOMOGENEOUS THIN CURVED LAYER WITH RAPIDLY VARYING THICKNESS

A regularly nonhomogeneous (composite), anisotropic, thin curved layer with rapidly oscillating material parameters and thickness is considered for the case when mean thickness and period scale have small magnitudes of the same order. A three-dimensional thermoelasticity problem for this layer is reduced to a homogenized shell model by means of an asymptotic homogenization method for periodic structures. The effective thermoelastic and thermal material parameters of this shell are expressed in terms of solutions for auxiliary local problems in the cell of periodicity. Using the solution of the boundary-value problem for the homogenized shell and the solutions of the local problems, one can obtain a three-dimensional microstructure of the stresses, displacements and temperature with a high accuracy

This general model is applied to the derivation of thermoelastic and thermal constitutive equations for network periodic shells. The relations obtained lay the foundation for a new continuous model of thermoelasticity and heat conductivity for network periodic shells and plates.     

1000MW机组高压主汽调节阀壳装焊技术研究

1000MW超超临界机组高压主汽调节阀作为公司引入的全新产品，其材料、结构都非常特殊，焊缝厚度大，操作空间狭窄，焊接难度非常大。通过开展一系列试验研究，攻克了新材料焊接问题，明确了该阀壳的具体装焊工艺方案，并最终通过试验和产品生产验证，成功解决了该高压主汽调节阀壳的装焊难题。     

灰铸铁缸体缸盖的材质选择与控制

分析当前我国缸体缸盖生产中材质的选择与控制，并探讨了今后的发展方向。通过采用低合金化、高碳当量、获得高温优质铁液和孕育处理等措施，可以有效地提高发动机缸体和缸盖等薄壁高强度灰铸铁件的成品率。     

A review on effect of phase change material encapsulation on the thermal performance of a system

This paper presents a detailed review of effect of phase change material (PCM) encapsulation on the performance of a thermal energy storage system (TESS). The key encapsulation parameters, namely, encapsulation size, shell thickness, shell material and encapsulation geometry have been investigated thoroughly. It was observed that the core-to-coating ratio plays an important role in deciding the thermal and structural stability of the encapsulated PCM. An increased core-to-coating ratio results in a weak encapsulation, whereas, the amount of PCM and hence the heat storage capacity decreases with a decreased core-to-coating ratio. Thermal conductivity of shell material found to have a significant influence on the heat exchange between the PCM and heat transfer fluid (HTF). This paper also reviews the solidification and melting characteristics of the PCM and the effect of various encapsulation parameters on the phase change behavior. It was observed that a higher thermal conductivity of shell material, a lower shell size and high temperature of HTF results in rapid melting of the encapsulated PCM. Conduction and natural convection found to be dominant during solidification and melt processes, respectively. A significant enhancement in heat transfer was observed with microencapsulated phase change slurry (MPCS) due to direct surface contact between the encapsulated PCM and the HTF. It was reported that the pressure drop and viscosity increases substantially with increase in volumetric concentration of the microcapsules.     

利用微调镗刀头实现高精度孔的加工

利用微调精镗镗刀头设计制造了系列专用镗杆，解决了壳体类零件在普通镗床上加工高精度孔时，因对刀困难而出现辅助时间过长并易产生废品的问题，使生产效率和产品质量得到大幅度提高。