Incoloy825材料在加氢裂化装置高压空冷器上的应用

对Incoloy825材料的焊接和抗腐蚀性能,以及在加氢裂化装置高压空冷器上的应用中应注意的问题进行了探讨.对此种空冷器在制造中如何解决异种钢焊接的难题,在清洗和水压试验中如何避免腐蚀等提出了建议.     

Incoloy 800H合金的应用和性能分析

通过对耐热耐蚀合金Incoloy 80 0H的性能分析 ,指出它与普通奥氏体不锈钢相比具有较优的抗氧化性能、耐蚀性和高温蠕变强度。针对催化裂化装置同轴式沉降再生器内部所用Incoloy 80 0H焊件易出现裂纹的问题进行分析 ,认为在施焊过程中由于合金凝固时有低熔点金属或化合物的液态膜残留在晶界区 ,该合金具有高的焊接热裂纹敏感性 ,若焊材选择不当 ,焊丝填充不充分、缺少保护气等将导致晶间裂纹产生。提出了该合金采用TIG焊接防止热裂纹产生的措施。     

Hydrogen-induced cracking behaviors of Incoloy alloy 825

The effect of hydrogen on the fracture behaviors of Incoloy alloy 825 was investigated by means of slow strain rate testing (SSRT).Hydrogen was introduced into the sample by electrochemical charging.The results show that surface microcracks form gradually during aging at room temperature when desorption of hydrogen takes place after hydrogen charging at a current density of 5 mA/cm 2 for 24 h.SSRT shows that the increase of ductility loss is significantly obvious as the hydrogen charging current density inc...     

Incoloy 800H/20g复合板材料焊接技术探讨

研究Incoloy 800H／20g复合板焊接工艺，以解决以镍基合金复合板材为主体的设备在焊接过程中易产生裂纹、气孔及成分偏析等问题。焊接实验选择H1Cr16Ni21作为过渡填充金属，采用惰性气体保护焊和手丁电弧焊2种形式焊接。实验结果表明，选择H1Cr16Ni21作为过渡填充金属，采用小电流、多道次焊接工艺，可得到质量良好的焊缝，焊缝宽度、焊缝余高、咬边及焊接错边均符合JB4730-94标准要求；力学性能优于20g耐热钢。焊缝成分与Incoloy800H接近。成功地解决了成分差异较大的2种材料焊接时易出现裂纹和气孔的问题。     

Carburization performance of Incoloy 800HT in CH4/H2 gas mixtures

Carburization performance of Incoloy 800HT has been studied after cyclic and isothermal exposures to CH₄/H₂ carburizing gas mixtures at high temperatures for 500 h. At 800 °C in 2% CH₄/H₂, Incoloy 800HT suffered external oxidation and carburization, the external continuous layer of reaction products consists primarily of Cr₇C₃, Mn_1.5Cr_1.5O₄, and FeCr₂O₄ with Fe(Cr, Al)₂O₄ as a minor phase. At 1100 °C in 10% CH₄/H₂, external carburization did not occur likely due to high carbon dissolution in the alloy substrate at this temperature. A thermodynamic analysis indicated that 1000 °C was an approximate critical temperature, below which the environment should result in mixed oxidizing/carburizing behavior, while above this temperature reducing carburizing behavior should occur. The experimental results approximately agree with the thermodynamic analysis. Metal dusting was not observed under highly carburizing conditions (a_C>1). The size and morphology of Cr-rich phases (or Cr-carbides) are both temperature- and time-dependent, while the external continuity is more temperature-dependent rather than time-dependent.     

换热式转化炉下猪尾管裂纹原因分析及改造建议

对已使用3 a、材料为Incoloy 800H合金的505C制氢装置换热式转化炉下猪尾管裂纹进行了分析,通过无损探伤、现场测量、材料元素分析、工艺运行状况、结构应力等方面的分析讨论,论证了裂纹产生的原因是由操作温度、结构应力等多种因素造成的,并对改进该装置提出了建议。     

800H合金长时间蠕变下的显微组织

对低负荷长时间蠕变试验下800H合金显微组织的研究表明:空洞在晶界M_(23)C_6碳化物的一侧形成,微裂纹通过一连串这样的小空洞而发展;晶界M_(23)C_6碳化物和相邻两晶粒之一有共格关系而与另一晶粒无共格界面,共格界面强化了晶界,这一强化作用可用蠕变激活能的提高来说明,晶界还有G相析出,但未发现合金中有γ'相的形成。合金能长时间保留网状的位错结构,晶界碳化物附近有位错塞积,亚晶界结构发展不充分,这与典型的回复蠕变是不同的。     

空冷器管束用Incoloy 825复合钢板设计厚度的探讨

介绍了空冷器管束用Incoloy 825复合钢板的设计厚度与复合后的成品厚度之间的差异,可能造成不满足设计要求的严重后果,并提出了设计制造时的注意事项。     

Incoloy825+12Cr2Mo1R复合板封头冲压加工研制

煤焦油深加工项目中的核心设备沥青预处理塔设计材料为Incoloy825(复层)+12Cr2Mo1R(基层)复合板。由于材料的特殊性和使用工况的复杂性,要求成形后封头即耐热又耐蚀。封头成形是本设备制造中的难点。采用高温热冲压成形和随后的正火加回火热处理,封头的各项技术指标达到了设计要求。文中介绍了复合板Incoloy825+12Cr2Mo1R材料特性,封头成形工艺,热处理工艺和合格指标。     

Incoloy800HT管线断裂失效分析

针对Incoloy 800HT管线断裂,检查原始施工记录,并通过扫描电镜和金相,及其应力分析等手段.研究结果显示,断裂处的材料出现了沿晶界析出的σ相和蠕变空洞并导致材料脆化,接管悬挂过重加速了蠕变空洞的形成,是导致接管断裂的根本原因.