陶瓷树脂内衬复合钢管介绍

采用树脂材料密暑离心铝热法制备陶瓷瓷钢管内衬层气孔，从而获得具有防护耐磨双重功能的复合管材。产品内衬层与钢管基体结合强度高，可在真空状态下长期运行，在高温下内初不鼓泡、不折皱。     

带环形焊缝双金属复合管屈曲失效研究

建立了带环形焊缝双金属复合管的三维有限元数值模型,在考虑双金属复合管复合成形过程所产生的残余应力的情况下,对在复杂载荷下带环形焊缝的双金属复合管的屈曲失效机理进行了研究,分析了环形焊缝、内衬管壁厚、外基管外径、内外管的初始间隙以及内衬管的屈服强度等因素对双金属复合管屈曲失效以及变形的影响.结果表明,环形焊缝的存在明显降...     

浅谈特高温烟道烟囱的防腐(一)

本文主要从技术角度对目前市场上特高温烟道烟囱各种防腐方案进行了对比,主要涉及有:乙烯基酯树脂玻璃鳞片胶泥、乙烯基酯树脂胶泥玻璃钢复合、乙烯基酯树脂胶泥勾缝砖板衬里(含泡沫玻化砖、耐酸砖、耐酸陶瓷等方案)、耐酸KPI胶泥、KPI胶泥勾缝砖板衬里、OM涂料、钛合金复合合金板、"混元体"方案、环硅聚合物杂化方案、萨维真柔性喷涂内衬方案、PFA可焊接聚四氟乙烯塑料内衬、玻璃钢挂片拼接方案、整体玻璃钢方案等。     

自蔓延高温合成陶瓷内衬复合管的研究进展

概述了自蔓延高温合成(SHS)技术的特点;介绍了陶瓷内衬复合管的制备原理和工艺;分析了SHS在热力学、动力学以及燃烧合成机理上的研究.从提高陶瓷层的结合强度、韧性、致密度、耐腐蚀性等方面,综述了提高SHS陶瓷内衬复合管性能的措施.并指出了SHS陶瓷内衬复合管的研究方向.     

石墨棒辅助SHS反应制备陶瓷内衬复合细长管

针对当前国内SHS小口径陶瓷内衬复合管制备长度短的研究现状,采用石墨棒辅助SHS反应的新型制备工艺,成功制备了长650mm的陶瓷内衬复合细长管,使小口径陶瓷内衬复合管的制备长度有了大幅度增加。利用新工艺制取的复合管内衬层厚度约为2mm,涂层组织结构致密,与基体结合紧密,各项力学性能相对于传统工艺均有所提高。     

玻璃钢管分层影响因素分析

分层是玻璃钢管道一种常见的质量缺陷,不仅影响管道的外观质量,还影响到管道内在的承压能力。本文主要就玻璃钢管在生产过程中出现的分层现象,从玻璃纤维、基体树脂、工艺等三方面进行了分析,并认为通过选择合适的玻璃纤维、基体树脂,在一定的工艺条件下可以减小、甚至杜绝玻璃钢管出现分层。     

稠油热采蒸汽输送管的氢蚀爆裂及其预防

对某油田稠油热采蒸汽输送管爆裂事故进行了分析.发现爆裂部位有局部腐蚀,腐蚀部位的基体中有脱碳及沿晶裂纹,且该处基体中有很高的氢含量.造成蒸汽输送管爆裂的原因在于氢蚀     

受约束内覆薄壁管对接焊温度场和应力场的数值模拟

针对复合管对接焊时,较厚的外层基材对内衬薄管焊接的温度场分布和应力场变化的约束影响,以及基材与薄管的接触效应,运用有限元法,在焊接过程使用"时间幅值"和"单元联接"等技术,建立了相应的有限元分析模型,计算了复合管对接焊内衬薄管的温度场变化和焊后残余应力的分布状况.通过计算,对薄管焊接速度、应力进行了分析讨论,并对薄板材料性质、结构尺寸、焊接热输入等焊接失稳变形的影响因素进行了研究.结果表明,薄板结构尺寸、焊接热输入对变形影响较大,而材料性质相对影响较小.     

L415QB/UNS S31603双金属复合管环焊缝失效原因分析

针对国内油气田较多应用的L415QB/UNS S31603双金属复合管环焊缝失效原因,采用金相显微镜、显微硬度计、扫描电镜和能谱仪对失效裂纹进行了形态、组织、成分分布和断口分析。研究发现,焊缝不同焊层间的组织差异,是焊缝开裂的组织因素;内衬与基管间贴合性能差造成的径向应力和焊缝横向应力,是焊缝开裂的力学因素。L415QB/UNS S31603复合管环焊缝焊接应采用ER309Mo L或E309Mo L填充材料,不应采用低合金E71T8-Ni1J焊材作为填充材料;焊接应选用较低热输入量的脉冲焊接工艺方法,以降低熔合比。     

玻璃鳞片衬里在大型化工装置上的施工及应用

玻璃鳞片衬里在大型化工装置上的施工及应用江镇海（南京化学工业（集团）公司氮肥厂）一、概述目前，国内树脂类材料用于金属设备内壁防腐的常见形式有：用树脂类防腐涂料涂装；用树脂胶泥作粘结剂的砖板衬里；用玻璃布增强的树脂类材料作内衬，即玻璃钢等。玻璃鳞片衬层...     

磁应力检测技术在双金属复合管检测上的实践

在高腐蚀性油气输送管道中,已经使用双金属复合管,其中内层是较薄的耐蚀合金内衬层,起到防腐蚀的作用,外层是较厚的普通钢质输送管用作结构支撑增加管材强度.内衬耐蚀合金层与钢质管材结合处的缺陷,以及管线焊接施工中造成的焊缝处的缺陷,通常会造成外层钢管内壁腐蚀的加速,引发管道腐蚀穿孔而发生泄漏,影响油气输送管道的安全运行.针对...     

离心法制备复合材料环的组织和性能

通过离心铸造法制备了外加WC颗粒增强铁基复合材料环,研究了复合材料环表面工作层内WC颗粒分布、界面结构、基体组织和力学性能以及高速磨损性能。结果表明:采用离心铸造法制备的外加WC颗粒增强铁基复合材料环是由外部WCP/Fe-C工作层和芯部Fe-C合金层组成的复合结构,其复合材料工作层厚度约30 mm,复合材料层中WCP分布均匀,体积分数约80%,复合层硬度80～85 HRA,芯部基体组织为贝氏体、石墨和少量复合碳化物,芯部基体硬度为73～76 HRA,冲击韧性大于10J/cm2,复合材料磨损率远低于高速钢,与WC硬质合金相当。     

离心铸造过共晶Al-Si合金自生梯度复合材料及其阻尼性能

通过改变离心铸造的转速 ,获得了内层有较多初晶Si,其余部分为共晶组织或初晶Si由外向内偏析的Al 16 %Si合金自生梯度复合材料。分析了复合材料的形成过程 ,考察了复合材料的组织 ,研究了复合材料各层的阻尼性能。结果表明 :Al 16 %Si合金自生梯度复合材料内层内耗是中、外层的 1.4倍 ,为充分发挥此材料的阻尼性能 ,应在频率高于 16 0Hz使用     

Designing a novel functional-structural NiTi/hydroxyapatite composite with enhanced mechanical properties and high bioactivity

Clinical applications require porous biomaterials, however, higher porosity levels and hydroxyapatite (HA) content hampers the mechanical properties like superelasticity. Here, a functional-structural composite consisting of a central NiTi shape memory alloy core with an outer macro-porous NiTi/HA layer was fabricated by spark plasma sintering (SPS). The central NiTi alloy provides desirable mechanical properties like high strength and superelasticity, while the outer layer with controllable pore size and bioactive HA, which strongly boosts the bioactivity. This work might provide a strategy for designing and fabricating multifunctional biocompatible materials that could be promising for bone implants.     

Wear failure of a leaded bronze bearing: Correlation between plant experience and laboratory wear test data

This paper describes an investigation on the failure of a large leaded bronze bearing that supports a nine-ton roller of a plastic calendering machine. At the end of the normal service life of a good bearing, which lasted for seven years, a new bearing was installed. However the new one failed catastrophically within a few days, generating a huge amount of metallic wear debris and causing pitting on the surface of the cast iron roller. Following the failure, samples were collected from both good and failed bearings. The samples were analyzed chemically and their microstructures examined. Both samples were subjected to accelerated wear tests in a laboratory type pin-on-disk apparatus. During the tests, the bearing materials acted as pins, which were pressed against a rotating cast iron disk. The wear behaviors of both bearing materials were studied using weight loss measurement. The worn surfaces of samples and the wear debris were examined by light optical microscope, scanning electron microscope, and energy-dispersive x-ray microanalyzer. It was found that the laboratory pin-on-disk wear data correlated well with the plant experience. It is suggested that the higher lead content (∼18%) of the good bearing compared with 7% lead of the failed bearing helped to establish a protective transfer layer on the worn surface. This transfer layer reduced metal-to-metal contact between the bearing and the roller and resulted in a lower wear rate. The lower lead content of the failed bearing does not allow the establishment of a well-protected transfer layer and leads to rapid wear.     

不锈钢复合钢管组织及其性能

采取外层先离心浇注10号钢,再浇注内层1Cr18Ni9Ti得到离心复合空心管坯,管坯内外表面加工后进行热挤压和冷轧,试制出了47mm×4.5mm的碳钢/不锈钢复合钢管,对不锈钢离心复合管坯生产复合钢管工艺路线进行研究,并对复合管金相组织、性能及结合层质量等方面进行分析。结果表明,复合管内外层冶金结合良好,晶粒明显细化,终轧后晶粒由铸态时3.0～3.5级变为7.0～8.0级,复合管压扁、弯曲及热处理后晶界腐蚀检验合格。     

Influences of ion migration and electric field on the layered anodic films on Al–Mg alloys

Anodizing of sputtering-deposited Al–Mg alloys containing 27 and 32 at.% magnesium in sodium hydroxide electrolyte is shown to develop two-layered anodic oxide films. The outer layer contains aluminium and magnesium species, and is enriched in the latter species relative to the alloy, particularly towards the film surface. The inner layer also contains the two alloy species but is depleted in magnesium, due to Mg²⁺ ions migrating to the outer layer faster than Al³⁺ ions. The ratio of the thickness of the outer layer to that of the film increases with increase of magnesium content of the alloy. The presence of aluminium species in the outer layer is attributed to the penetration of the outer layer by oxide of the inner layer with lower ionic resistance. This mechanism of film growth appears to be sustainable to alloy concentrations to 40 at.%Mg, when the inner layer may no longer form. Enrichment of alloying elements can accompany film growth on Al–Mg alloys, as shown by enrichment of tungsten to 2–3 × 10¹⁵ atoms cm⁻² in an Al–26 at.%Mg–1 at.%W alloy.     

钎焊过程原位合成高强度银钎料

AgCuZnSn合金具备高强度、成分无害化的优势,在绿色制造中应用前景广阔,但Sn元素的加入导致的成形性能下降,限制了其使用. 为克服该不足,设计了一种使用AgCuZn/ZnCuAgSn/AgCuZn复合焊片在钎焊过程中原位合成AgCuZnSn高强钎料的方法,采用的复合钎焊片外层为AgCuZn低熔合金,内层为ZnCuAgSn合金,二者熔点接近且内层合金低于合成后钎料熔点,复合钎料的加工性优于同成分的AgCuZnSn钎料. 使用复合钎焊片进行了感应钎焊不锈钢试验. 结果表明,钎焊过程中两种合金几乎同时熔化,经瞬间保温后可充分熔合,获得高强度钎缝,采用该工艺获得的接头强度高于常规钎焊连接强度.     

Corrosion behavior of iron-aluminum alloys and its composite steel in sulfuric acid

The corrosion behavior of an iron-aluminum alloy with bcc structure and a composite of an iron-aluminum and a steel was studied in H₂SO₄ solution. The corrosion resistance deteriorates with increasing aluminum content of an iron-aluminum alloy. XPS measurements showed a magnetite formation on the corroded surface and a preferential corrosion of iron. The corrosion resistance for the composite of an iron-aluminum alloy and a CrMo steel is comparable to that of a CrMo steel. This implies that a corrosion-resistant composite is achievable by controlling the aluminum content of the Fe-Al alloy without the additives.     

基于有限元模拟的20/316L复合管拉拔成形分析

为研究20/316L复合管拉拔成形过程,给出拉拔成形时轴向应力和径向应力对成形区内金属流动的影响,运用非线性有限元分析软件ABAQUS/Explicit,对20/316L复合管拉拔过程进行仿真,得到了拉拔完成后稳定拉拔阶段的轴向应力、径向应力及等效塑性应变的分布,分析了拉拔全过程内外管之间残余接触压力的变化,以及稳定拉拔阶段拉拔力的分布规律。实验表明,经参数优化后的硬质合金拉拔模具的工作寿命是未优化前模具的6倍,并且得到了具有优良综合性能的内衬不锈钢复合管,该研究可节约分析时间,降低成本,又可为提高复合管质量、延长模具寿命提供参考。