小顾问

小顾问要解决液化石油气钢瓶缩口对接理弧自动焊主焊道内咬边问题，可将缩口敞开一些，使铁水减少压力，使高热金属蒸气压力大小适当，不致形成钢瓶内咬边。经透视，钢瓶不再有内咬边那道黑影。（廖美东）小顾问@廖美东...     

汽车用压缩天然气钢瓶易腐蚀区域的确定

通过对五只汽车用压缩天然气钢瓶(以下简称CNG钢瓶 )产生腐蚀的原因分析，确定了其易腐蚀的区域，并对该区域的成因进行了分析，同时针对C NG钢瓶因腐蚀导致瓶体强度降低，将使其安全使用系数降低的现象，提出了具体的防护措施 .     

高温正火对34Mn2V钢瓶力学性能的影响

1前言我厂生产的钢瓶选用攀钢提供的34Mn2V非调质钢制造，钢坯经加热、冲孔、拔伸和收口成形后，还须通过正火处理才能满足使用要求。然而，原材料34Mn2V钢的化学成分是在一定范围内波动的，很容易引起钢瓶正火后的力学性能不稳定。在生产中，我们发现一些原材料的碳锰含量偏下限的钢瓶，按常规正火工艺（840℃～880℃×63min，空冷或风冷）处理，经抽样检查力学性能指标偏低，达不到技术要求（见表1）。对不合格的钢瓶连续进行重复正火（按规定重复正火次数不多于两次），而重复正火两次其力学性能仍不合格的钢瓶，只有大批量报废，造成…     

钢瓶环缝焊接质量的改进

近几年来，我国制造液化石油气钢瓶厂家采用缩口结构越来越普遍，因为缩口结构先进、加工工序少、成本低、效率高、且质量好。过去我厂一直采用埋弧焊(Ф2mm H08A焊丝)非连续二次焊接成形工艺，在制造过程中存在：钢瓶环缝烧穿率高；钢瓶的爆破体积膨胀率与焊接接头的抗拉强度不匹配；钢瓶环缝焊接质量较差，抽透合格率低等问题。     

在用液化石油气钢瓶底部泄漏原因及防止措施

1　问题的提出1999年我们在液化石气钢瓶 (以下简称钢瓶 )的定期检验中 ,共检验了 16万只 ,因存在超标缺陷且无法修复而报废的钢瓶共 76只 ,其中 ,由于钢瓶底部泄漏而报废的钢瓶共 32只 ,约占报废数的 4 2 %。钢瓶泄漏是在钢瓶的气密试验中发现的。在采用浸水法进行气密试验时 ,我们发现钢瓶的底部发生泄漏 ,宏观上表现为出气泡 ,有的间断上升 ,有的线状上升 ,甚至有的钢瓶几处同时发现上述现象 ,经仔细观察 ,泄漏的部位是在底座与钢瓶的连接处。据调查 ,泄漏的钢瓶是由不同厂家制造 ,其使用时间为 6～ 16年不等 ,钢瓶底部与瓶体是采用三点…     

乙炔钢瓶抛丸清理机

乙炔钢瓶抛丸清理机谢汝 （广州市南方铸造机械厂广东清远市：５１１５００）主题词：乙炔钢瓶，抛丸清理机广州市南方铸造机械厂于１９９２年为广州市化工厂钢瓶检测站承制了一台乙炔钢瓶抛丸清理机，用于乙炔钢瓶检测前表面除锈处理，以提高检测质量。并于１９９３年１?..     

液化石油气钢瓶环缝锁底接头两道埋弧焊工艺

介绍了液化石油气钢瓶环缝锁底接头、两道埋弧焊工艺。锁底接头成形加工工艺简单，上下封头组对操作便利。环缝焊接质量稳定可靠，生产率高，适用于大规模机械化生产，是一种能使钢瓶生产实现优质高效的焊接方法。     

钢瓶的热处理

钢瓶是用于盛装压缩气体或高压液化气体的可重复充装的移动式钢质无缝气瓶，公称工作压力为７８５～２９４２ＭＰａ，水容积为０４０～８０Ｌ。钢瓶系高压容器，必须严格选材和热处理。１选材和性能要求合理选材是保证钢瓶质量的关键。钢瓶用钢一方面要有一定的塑性...     

钢瓶的热处理

公称工作压力为7．85－29．42MPa，水容积为0．40－80L，用于盛装压缩气体或高压液化气体的可重复充装的移动式钢质无缝气瓶，简称钢瓶（下同）。鉴于钢瓶应其高压容器的性能要求，必须进行严格的选材和热处理。1．选材和性能要求合理选材是保证钢瓶质量的关键，钢瓶用钢一方面要有一定的塑性、韧性（寒冷地区用尚要一定的低温冲击韧性），以保安全使用；另一方面又要有较高的强度，以尽量减轻其重量。钢瓶必须采用碱性平炉、电炉或吹氧碱性转炉冶炼的镇静钢。钢中的碳、硫、磷和铜的含量不应超过表1规定。我国钢瓶常用材料牌号及化学成分…     

液压边压装置

液化石油气钢瓶封头在压力机上拉伸时需对其施加一个压边力,没有压边力或者压边力太小,会使零件起皱,压边力过大,会使零件的拉伸减薄量增加,甚至拉裂。我们在拉伸钢瓶封头的300吨油压机上设     

聚氨酯漆施工工艺研究

为保证聚氨酯漆膜质量,对聚氨酯涂料施工工艺进行了研究.阐述了聚氨酯漆施工工艺:喷涂前表面预处理方法、喷涂前表面检查的内容、漆膜厚度、干燥方法.指出必须对施工中的配漆、温度、湿度、清洁度、黏度、喷漆间气压等环节进行控制.同时提出了施工时常见的流挂、桔皮、麻坑、针孔、起泡等病态的防治方法.结果表明:只有严格控制喷漆过程才能保证聚氨酯漆膜质量.此项研究对实际生产具有较好的指导意义.     

Assessment of steel surface roughness and waviness in relation with paint appearance

Paint appearance is an important factor in the overall product quality of steel sheet, especially in the automotive industry. The present paper deals with the functional behaviour of the surface texture according to paint appearance. The main results on the improvement of paint appearance of outer car body panels, obtained with coated and uncoated cold rolled steel, textured with EBT-rolls, is reviewed.There are different methods to relate steel sheet surface texture to the appearance after painting. From the literature it is found that waviness has a detrimental effect on the surface appearance after painting. Different roughness and waviness parameters are compared in order to find a good relation with paint appearance.The following surface texture parameters are evaluated in this study: roughness parameters Ra, peak count Pc, waviness parameters Wca and amplitude between 0.5 – 5mm (Fourier analysis) and envelope parameters motif W and Ra-macro, measured with a spherical stylus of radius 1.5mm.Classical parameters such as Ra and Pc are only able to evaluate paint appearance for one single texturing process, and within very limited range. The ability to predict paint appearance by Ra-macro and Wca also seems to be limited, because of their dependency on the roll texturing technique. Based on extensive testing, it is suggested that Fourier analysis might be the best approach to predict the appearance after painting, and this independently of the texturing process.The results clearly show the improved appearance of Sibetex textured sheets compared to conventional textured sheets. This is due to the fact that, with Sibetex sheet, a reduction in waviness can be achieved.     

矮寨特大悬索桥钢结构防腐蚀施工工艺技术

论文介绍了矮寨特大桥钢结构防腐蚀涂装方案,编制了钢梁在厂内的防腐蚀施工工艺流程图,详细阐述了喷砂除锈、电孤喷涂、油漆涂装、二次表面处理等各工序的工艺参数、质量标准和检验方法。     

我国缸筒用高精度冷拔钢管的技术与发展

介绍了运用平面应变理论,在预应力高刚性全液压冷拔管机上,通过专减壁厚拔管的变形方式,直接拔制液压气动缸筒用管。分析了拔管时的拔制力、合理减壁率及冷拔工艺与设备特点。提出了全面控制工艺系统精度是提高产品质量的关键。实践证明,采用高精度冷拔钢管制造缸筒,其强度、刚度高,耐磨性能好,且具有内表面硬外表面韧的特点。高精度冷拔缸筒管是直接制造各类缸筒的理想金属材料。     

The corrosion behavior of zinc-rich paints on steel: Influence of simulated salts deposition in an offshore atmosphere at the steel/paint interface

The corrosion behavior of an epoxy zinc-rich paint on interface-contaminated carbon manganese-silicon steel was studied. SEM observation on the cross-section of the paint indicates that the zinc corrosion products grew from the surface to the inner of the paint and salts contamination promoted the growth at locations close to the steel/paint interface. The results of electrochemical impedance spectroscopy show that the corrosion resistance of the contaminated paint was significantly influenced by diffusion of zinc corrosion products during the initial stage of immersion, and diffusion of iron corrosion products at the end of immersion. Three transmission line models were applied to account for the corrosion process of the uncontaminated and contaminated zinc-rich paints.     

水性硅酸盐溶胶型涂料对钢筋混凝土耐久性的影响

分析了钢筋混凝土腐蚀破坏的主要原因是钢筋腐蚀导致的混凝土胀裂.为保护钢筋混凝土研制了一种水性硅酸盐溶胶型涂料并研究了该涂料对混凝土内置网筋的保护作用及经涂料涂覆的混凝土氯离子渗透性和高压渗水性能.结果表明,涂履水性硅酸盐溶胶型涂料可明显提高与改善混凝土的耐久性.     

带锈涂料的分类及研究现状

带锈涂料可以在有一定锈蚀的钢铁表面进行涂装,适合于表面处理质量不易达到要求的钢铁表面的防腐,尤其适合于船舶、桥梁、海港码头、海洋工程等大型钢结构维修时的涂装。较系统地介绍了当前使用的转化型、稳定型、渗透型和功能型带锈涂料的原理、性能、应用及存在的问题,综述了带锈涂料的基料、颜料、转化剂、渗透剂的使用和研究现状,综述了带锈涂料的测试方法。对于船用带锈涂料,应着重考察漆膜的附着力、抗起泡性能和耐浸泡性等指标,研究锈在涂层中的转化行为,对船体用带锈底漆还应着重考察漆膜的耐阴极剥离性能。深入进行带锈涂料的机理研究,开发高性能树脂、颜料、锈转化剂和渗透剂,研发经济、环保、高性能的带锈涂料,尤其是研发高防腐蚀性能的带锈涂料,是我国涂料行业亟待研究和发展的重要方向。     

Failure of aluminium metal spray/organic duplex coating systems on structural steel

Abstract

Individually, aluminium metal spray (AMS) and organic paints are well established as effective protective coatings for steel substrates. These coatings are also frequently used together as duplex systems where their combination should produce a synergistic effect. However in certain, mainly marine, environments premature failure of such coatings, involving early blistering of the paint, has been observed in service after 3–5 years. This work aims to understand the mechanisms associated with the early failure of the AMS+paint duplex system. Various panels were initially prepared for accelerated exposure using combinations of coatings on blast cleaned steel. Visual inspection after salt spray exposure revealed the presence of white corrosion product, which was confirmed afterwards as Al(OH)₃. Observation of the coating microstructures before and after salt spray exposure confirmed significant local corrosion of aluminium underneath the paint layer. It is suggested that failure of the duplex AMS/paint system initiates by corrosion of the porous AMS underneath the organic layer then progresses by the combined effect of volume expansion due to formation of Al(OH)₃ and cathodic blistering of the paint from the AMS surface.     

径向进给射流电解车削圆柱表面试验

径向进给射流电解车削加工是针对难加工材料回转体零件表面特征,利用电解液从阴极刀具内部喷向工件,刀具沿径向逐渐向工件进给进行电化学溶解的加工方法。通过流场仿真,优选出阴极刀具结构,利用10%的NaNO3溶液对316L不锈钢材料圆柱表面进行试验研究,分析平衡间隙、加工电压、工件转速、电解液压力对材料去除率和工件表面粗糙度的影响。结果表明:利用优选的刀具,对直径20 mm、高度10 mm的316L不锈钢圆柱表面径向单边车削0.5 mm,材料去除率可达0.391 g/min,表面粗糙度Ra<0.2μm。     

无取向硅钢环保绝缘涂层的制备与性能

目的寻求替代含铬绝缘涂料的环保绝缘涂料。方法采用水溶性磷酸盐和水性树脂自制水性涂料,在无取向硅钢表面制备绝缘涂层,研究其固化工艺,并与国内涂料进行理化指标和涂层性能(附着力、表面电阻、耐腐蚀性能、耐热性)对比。结果自制绝缘涂料无刺激性气味,稳定性好,使用寿命长,在固化时间20~24 s、固化温度480~520℃的条件下,可在无取向硅钢表面制得均匀、光亮的银灰色绝缘涂层。绝缘涂层附着力为A级,12 h中性盐雾试验腐蚀面积低于5%,在750℃高温退火2 h不掉粉,表面绝缘电阻为297Ω/mm2(1.0~1.2μm)。结论自制水性绝缘涂料为环保型单组分涂料,与国内绝缘涂料的涂层性能相当,满足国内钢厂产品技术要求。