35t空心钢锭的制造

介绍了35t空心钢锭外模的选取,芯筒结构形式的设计,冷却介质压缩空气参数的选择,底盘的设计及浇注工艺参数的制定.根据这一系列研究结果,成功生产了空心钢锭,为今后大规格空心钢锭的研发奠定了基础.     

大直径圆波浪钢锭的研制与开发

根据大直径、厚壁及超长无缝钢管的市场需要,开发出适用于斜轧穿孔+周期轧管方式的一次成材轧管用大直径圆波浪钢锭.该钢锭采用了波峰小、波谷凹人深度浅、边数多、接近于圆形的断面,锭模内腔小正锥度大高宽比等特殊设计;生产时采取低模体温度、低钢水过热度、低浇注速度及钢锭长时间缓冷等措施,解决了此类钢锭易产生表面裂纹的难题.生产的...     

攀钢集团成都钢钒有限公司“轧管用空心钢锭工艺技术研究”等4项成果通过技术鉴定

<正>2010年2月4日,攀钢集团成都钢钒有限公司完成的"轧管用空心钢锭工艺技术研究"、"大型石化装置专用系列碳钢管开发"、"含硼缸体用管研究与开发"及"轧管用大断面圆波浪钢锭的研制与开发"等4项成果通过四川省科学技术厅组织的技术     

基于空心钢锭大型筒体锻件开坯锻造研究

空心钢锭的铸态缺陷主要存在于距空心钢锭内壁1/3~1/2处,其独特的凝固特点决定其开坯锻造和实心钢锭有很大区别。通过Deform-3D数值模拟软件,探究空心钢锭在不同压下率下的芯轴拔长变形规律,得到拔长不利于改善空心钢锭内部缺陷。研究空心钢锭在不同芯轴直径、不同压下率下的芯轴扩孔变形规律,得出芯轴直径的选择应保持μ在60%~75%范围内、压下率处于25%~35%较为合理。探究芯轴扩孔对空心钢锭球形、径向、轴向、切向空洞型缺陷的压实效果,结果表明:芯轴扩孔可以闭合空心钢锭中的球形、切向和轴向空洞,对径向空洞有明显的压实作用,验证了采用芯轴扩孔作为开坯工步的可靠性。     

用震实式造型机制造钢锭模砂芯

在钢锭模砂芯生产过程中,采用自制简易缠芯骨禾草绳机构与震实造型机制造砂芯的论述及金属模芯盒设计要领与生产实践上应用和效益。     

有芯弯管模及其芯棒磨损的预防

１引言某摩托车车体主弯管如图１所示，材料采用５４ｍｍ×３ｍｍ钢管，经弯曲加工而成。由于该管件在车体上位置特殊，故对其加工精度要求较高，在生产过程中采用反变形法有芯弯曲模具加工。管料加工的方法很多，比较常用的有模具压弯、弯管机上弯曲等，前者对工装的要求较低，但弯曲精度也较低。在实际生产中，对于一些批量大、精度要求高的管件弯曲加工通常采用专用弯管机，该件采用ＷＡ２Ｙ＿６０（ＳＭ）型弯管机生产。图１主弯管２有芯弯管模有芯弯管如图２所示，弯管模块１和夹紧模块２的作用是将管料夹住，然后使管件缠绕弯管模１…     

散热器进出水管剖切模设计

散热器进出水管剖切模采用浮动凹模芯轴结构形式。该结构完全适应管类零件剖或切的冲压加工需要 ,浮动凹模芯用以补偿轴与凹模的间隙 ,消除产品变形     

大型筒体锻件空心钢锭锻造工艺探索

针对反应堆压力容器等大型筒体锻件采用实心钢锭存在的钢锭利用率低和生产周期长等缺点,对空心钢锭锻造工艺进行优化。通过铅试件物理模拟和DEFORM-3D数值模拟,研究空心钢锭在不同压下率、芯轴直径、砧宽、芯轴转角、接砧量和布砧方式下镦粗、芯轴拔长和芯轴扩孔时的变形规律,提出了避免空心锻造缺陷的方法,可为国产大型筒体锻件的空心钢锭锻造工艺规范制定提供参考依据。     

空心型材分流模优化设计的有限元模拟

利用UGNX软件建立分流模实体模型,利用MSC.supeform有限元模拟软件对分流模挤压过程进行热力耦合有限元模拟,研究了挤压过程中模芯的变形情况.结果表明,即便是对称性较好的矩形管分流模,模芯在横向上也会发生一定量的偏移及扭转,影响型材的尺寸精度.对于大多数空心型材来说,其断面往往都是不对称的,仅依靠设计者的经验和判断是很难避免模芯变形的,而采用有限元模拟的方法,则可以较为方便地找到解决这种变形的方法,为设计提供科学的依据.     

中大口径高合金钢无缝管材生产新工艺研究

阐述了采用“离心浇铸空心坯＋管坯特殊处理＋热辊模连续顶轧成形”短流程工艺生产中大口径高合金钢管材的新方法：通过对试制管材的力学性能、腐蚀性能和金相组织的观察,表明本短流程新工艺由于突破了穿孔的固有局限,适合生产难变形的高端管材,且管材具有优良的综合使用特性;节能降耗的优势明显（粗略估计可节能节燃料各10％）。     

特大型球墨铸铁钢锭模的铸造工艺

介绍了重量38t的大型钢锭模球铁件的生产工艺。采用底注式浇注系统,锭模内孔型芯采用焊接钢管芯骨,外层30mm为呋喃树脂砂层。铸件顶部延长200mm作为本体冒口,其顶面还设有4个安全小冒口。浇注后钢管芯骨内注入冷却水,对铸件下段进行强制冷却。利用球墨铸铁石墨化膨胀进行自补缩解决了铸件内部的缩孔、缩松缺陷,使生产的铸件达到质量要求。     

Characteristics of a vertical semi-continuous casting process using a heat insulating mould for aluminium alloys

In order to improve the quality of aluminium and aluminium alloy ingots for use in plastic forming, a new vertical semi-continuous casting process has been devised, using a heat insulating refractory as the mould. This paper reports the fundamental characteristics of the process and the quality of the ingots that are obtained using 6063 alloy. The inside of the mould is tapered, with the diameter of the upper opening 48 mm and the diameter of lower opening 51 mm. The height of the mould is 42 mm. Under specific conditions, ingots with very smooth surfaces were obtained. When the surface condition and changes in diameter of the ingots were examined in detail, it was found that for specific condition the solidifying interface emerged at the lower end of the mould and solidification then occurred in areas not in contact with the mould surface. Thus ingots with very smooth surfaces were obtained. It was also found that ingot quality was high with fine, uniform structures free from segregation.     

环形加热炉设计浅析

环形加热炉在钢管生产中起着重要的作用,其设计是否合理,将直接影响钢管产品的质量和钢管轧制生产节奏。介绍了如何合理确定环形加热炉的设计参数和布料角,以及炉底砌筑结构设计、炉底与炉膛中心差值的选取方法等,并提出了新的环形加热炉烘炉方案。实际应用表明,所设计的平均直径24m环形加热炉运行工况良好。     

Solidification microstructure of M2 high speed steel by different casting technologies

The present work investigated the solidification microstructure of AISI M2 high speed steel manufactured by different casting technologies,namely iron mould casting and continuous casting.The results revealed that the as-cast structure of the steel was composed of the iron matrix and the M2C eutectic carbide networks,which were greatly refined in the ingot made by continuous casting process,compared with that by the iron mould casting process.M2C eutectic carbides presented variation in their morphologies and growth characteristics in the ingots by both casting methods.In the ingot by iron mould casting,they have a plate-like morphology and grow anisotropically.However,in the ingot made by continuous casting,the carbides evolved into the fiber-like shape that exhibited little characteristics of anisotropic growth.It was noticed that the fiber-like M2C was much easier to decompose and spheroidize after heated,as a result,the carbides refined remarkably,compared with the case of plate-like carbides in the iron mould casting ingot.     

锅炉用焊接钢管的制造技术

简述了锅炉用焊接钢管的优势,国内外锅炉用焊接钢管的生产发展概况以及我国焊接钢管用于锅炉制造的情况。详细介绍了锅炉用焊接钢管的质量要求、品种和规格,锅炉用焊接钢管的几种生产工艺方法,典型的制管工艺流程和生产关键技术。对锅炉用焊接钢管生产提出了几点建议。     

Numerical Simulation of Macrosegregation in Steel Ingot CastingEI北大核心CSCD

Many key forging components of heavy equipment are manufactured by large steel ingots. Macrosegregation in steel ingots is a key defect formed during the solidification process. Over the past few decades, numerical modeling has played a more and more important role in the study of macrosegregation. Various models have been developed and applied to different ingot casting processes. This paper focused on the application of macrosegregation models to the steel ingot. Firstly, the formation mechanism and influencing factors of macrosegregation were introduced. Then, the existing macrosegregation models and their recent development were summarized. Macrosegregation models accounting for such mechanisms as solidification shrinkage- induced flow and mushy zone deformation were analyzed, respectfully. To model macrosegregation due to solidification shrinkage, the key was to solve the free surface. A simple derivation showed that the multi-phase (including gas phase) models were equivalent to the VOF-based segregation models in dealing with the shrinkage-induced flow. Finally, our recent research work on numerical modeling of macrosegregation in steel ingots was illustrated, including application of the developed multi-component and multi-phase macrosegregation model to a 36 t steel ingot, and numerical simulation of multiple pouring process. The carbon and sulphur concentrations at about 1800 sampling points, covering the full section of a 36 t ingot, were measured. By detailed temperature recording, accurate heat transfer conditions between the ingot and mould were obtained. Typical macrosegregation patterns, including the bottom-located negative segregation and the pushpin-like positive segregation zone in the top riser, have been reproduced both in the measurements and the predictions, The carbon and sulphur concentrations predicted by the three dimensional multi-component and multi-phase macrosegregation models agreed well with the measurements, thus proving that the model can well predict the macrosegregation formation in steel ingots. As for the multi-pouring process simulation, the results show a high concentration of carbon at the bottom and a low concentration of carbon at the top of the mould after the multi-pouring process with carbon content high in the first ladle and low in the last ladle. Therefore, the multiple pouring process could get the initial solute distribution with the opposite form of segregation. Such carbon concentration distribution would reduce the negative segregation at the bottom and the positive segregation at the top of the solidified ingot, thus proving the ability of the multiple pouring process for the control of macrosegregation.     

模拟软件在优化上注钢锭模设计中的应用

采用AnyCasting模拟软件对15 t上注钢锭进行了凝固过程模拟.通过模拟结果分析优化钢锭模参数,降低试制成本,改善钢锭质量,消除缩孔缩松缺陷,并为保温帽口式钢锭及50t以上的上注钢锭模拟提供指导.     

2.3 t铸锭的奥氏体气阀钢轧制工艺探索及生产

研发了2.3t铸锭的5Cr21Mn9Ni4N(21-4N)奥氏体气阀钢轧制开坯工艺.热模拟此钢种在高温状态的抗拉强度Rm和断面收缩率Z,并根据生产设备功能状态,分析确定了适合该奥氏体气阀钢2.3t铸锭轧制开坯的温度范围,以及相应的初轧加热工艺制度和初轧机压下规程及轧制方法.对轧制能力与热剪机能力的验算,确认Φ750 mm初轧机、650 t热剪机等设备具备轧制2.3t铸锭生产160 mm×160 mm奥氏体气阀钢的可行性.产品质量满足奥氏体气阀钢线材盘卷单重≥1.5t的供坯需求,实现了规模化轧制生产.新工艺较大幅度地降低了吨钢生产的天然气消耗和动力电消耗、有效地降低了生产成本.