高韧性X80管线钢埋弧焊焊丝的研制

根据Q／SYGJX0102--2007《西气东输二线管道工程用螺旋缝埋弧焊管技术条件》,采用Mn．Mo—Ti—B合金系研制成功1种高韧性X80管线钢埋弧焊焊丝H80。结果表明,H80焊丝与烧结焊剂F80匹配,在1．65mm／min焊速下,钢管焊缝金属的力学性能满足标准要求,焊缝组织可实现以得到针状铁素体组织为主的设计目标。     

长输管线工程站场、阀室焊接技术

结合西气东输二线管道工程,介绍了长输管线的站场、闽室及站内管网的焊接重要性.同时介绍了西气东输二线工程站场焊接工作要点、执行的主要技术标准,并且重点分析了站场焊接工作的难点等.     

MgO-CaO-SiO2焊接熔渣离子活度的热力学分析

针对焊接熔渣分子理论及离子理论存在的局限,基于冶金界近年来提出的熔渣共存理论,结合MgO-CaO-SiO2高温三元相图确定的结构单元,利用质量平衡原理建立了MgO-CaO-SiO2三元熔渣离子活度热力学计算模型,并借助于Matlab计算工具进行数值求解.计算结果表明,该模型可同时兼顾熔渣的分子理论和离子理论,离子活度随碱度的变化与碱度理论及直流焊接冶金电化学实验结果一致,在焊接化学冶金定量研究方面显示出良好的应用前景.     

Oblique Y-groove cracking test of the welding cold cracking susceptibility of domestic X-70 pipeline steel

“Gas Transmitting From West to East Project“ is significant.it should ensure the welding quality and safety of pipeline.The task is very arduous to guarantee the quality of the projcet in the condition of long line.complex weather and geolgy features.in this paper,the welding cold cracking susceptibility of domestic X-70 pipeline steel adopted by the project, which is one of the most interesting questions of welding quality about petrol pipeline,was studied by means of oblique Ygroove cracking test.The crack ration of surface and section was tested under the conditions of different welding materials and preheat temperature.The thickness of plate stell was 14.7mm and 10.3mm.The results reveal that X-70 pipeline steel has good crack resistance.The research has important value for the construction of large-scale pipeline engineering and the application of domestic X-70 pipeline steel.     

油气管道焊接施工过程中的磁偏吹

在石油、天然气长输管道焊接施工过程中，常常会遇到电弧偏吹现象。有些电弧偏吹产生原因难以确定，严重时甚至将焊丝、焊条吸到一边，造成连续或断续咬边、未焊透、熔合不良等缺陷，甚至无法施焊，严重影响焊接过程和焊缝成形。为此分析了油气管道焊接施工过程中磁偏吹的产生机理，并在长期的管道焊接施工经验的基础上总结了几种能够有效消除和减少磁偏吹的方法。     

X70与CF62异种钢焊接工艺

通过对X70和CF62钢焊接接头低温冲击试验和组织的测定，结合“西气东输”工程站场内焊接施工的实际要求，研究了以上两种材料的异种钢焊接要点，该工艺已作为“西气东输”工程站场内的焊接工艺方案，并可为异种钢管的焊接提供可靠的技术参考。     

Interfacial energy and match of cold pressure welded Ag/Ni and Al/Cu

The technology of cold pressure welding was adopted to achieve the bonding of Al/Cu(limited soluble and forming compounds),Ag/Ni(hardly mutual soluble),and the relative state of interface was tested by HREM.The results indicate that stable interface is always corresponding to the low interfacial energy value;the stable interface is not coherent but partly-coherent because of the twisting of grain boundary caused by pressure,meanwhile existing dislocation.Namely,the interfacial match and other states under the condition of cold pressure welding are different from the situation that under the condition of thermal action.Moreover,theoretical analyses and calculation on the base of thermodynamics,crystallogeny ,solid physics etc,were discussed.     

控轧钢钢管热煨弯管的应用与发展趋势

油气长输管道用弯管一直依赖进口UOE钢管来煨制,如果使用螺旋缝焊管热煨弯管,可以提高我国弯管制造技术和水平,同时可节约大量的外汇,降低管道建设的成本.通过国内外热煨弯管的应用和研究情况对比分析,认为采用螺旋缝焊管热煨弯管是可行的.     

高强度级别管线钢的焊接

我国石油天然气长输管线正面临飞速发展的历史时期,使用高强度级别管线钢,已成为国际上管线建设的重要趋势.重点介绍了高强度级别管线钢的发展情况、显微组织特点;分析了管线钢的焊接性.对于德国、加拿大等国际上X80管线钢的工程实例进行了简要的介绍;同时,对我国冶金、制管行业近年来研制开发X80板材、管材的情况进行了综述;尤其对我国管道行业X80钢焊接研究及实际工程应用的准备工作进行了概述.从而指出我国的冶金、制管、焊材、焊接设备、管道研究、施工、管理及技术部门都应抓住机遇,为管道事业作出贡献.     

Characterization of the microstructure and hardness of the HAZ in a 800MPa grade RPC steel

The microstructure and hardness of the HAZ in a 800MPa grade ultra-low-carbon microalloyed steel were studied.The results indicate that the heat affected zone(HAZ) of the RPC (Relaxation- Precipitation- Controlling) steel possesses a continuous gradient structure, and can be classified into three zones, i. e. CGHAZ (coarse-grain HAZ) , FGHAZ (fine-grain HAZ) and ICHAZ(intercritical temperature HAZ). The microstructures in the HAZ are all composed of bainite-like structure.The microstructure in the CGHAZ mainly consists of lath-like bainite and granular bainite . The influences of heat input and t8/5 on the hardness in the HAZ of RPC steel are notable. With the increase of heat input and t8/5, the softening tendency of HAZ becomes obvious. The hardening phenomenon that normally occurs in the CGHAZ does not take place with this steel in the range of experimental conditions. The softening in the ICHAZ is bound to occur. Hence appropriate welding technologies need to be selected.