氧－液化石油气焰快速精密割嘴的研制

通过分析氧气切割的过程和氧－液化石油气焰的切割特点，论述了凹凸型割嘴具有较高的切割氧动量、纯度保持能力和预热火焰温度的机理。介绍了液化石油气凹凸型割嘴的结构及主要参数。     

氧—液化石油气焰快速精密割嘴的研制

通过分析氧气切割的过程和氧－液化石油气焰的切割特点，论述了凹凸型割嘴具有较高的切割氧动量，纯度保持能力和预热火焰温度的机理。介绍了液化石油气凹凸型割嘴的结构及主要参数。     

氧—液化石油气切割的推广应用

介绍氧-液化石油气(丙烷)切割的特点、大面积推广应用的意义及如何解决大面积推广应用中的切割设备、机具、气源、人员培训等具体问题。     

氧甲醇汽油火焰燃烧性能分析与切割试验

根据热力学理论分析和讨论了氧甲醇汽油的燃烧过程,分析火焰燃烧时各区域的产热及其能量平衡关系,计算了甲醇在不同混合比例下的火焰燃烧理论温度。根据当前国内甲醇汽油的应用情况,提出利用氧甲醇汽油作为金属氧气切割方法的新型燃料。通过一系列切割试验表明,氧甲醇汽油在甲醇比例为10%~50%范围时,火焰燃烧稳定,切割质量优良,能满足普通钢材的火焰切割要求。     

氧乙醇火焰燃烧性能及其切割性分析

按热力学理论讨论了氧乙醇的燃烧过程,分析火焰燃烧时各区域的产热及其能量平衡,计算火焰理论温度,提出氧乙醇火焰可以作为金属氧气切割方法的热源.通过切割试验,证明该方法可行,并且切割质量优良.     

液化石油气燃烧实验装置设计

液化石油气应用广泛,易发生火灾和爆炸事故。根据液化石油气燃烧特性和救援研究的需要,设计了一套液化石油气燃烧实验装置,可完成不同压力、流量下燃烧温度和热辐射量的测量和采集。实验装置的合理设计为大型液化石油气储罐的燃烧和应急救援研究奠定了基础。     

四种燃气的基本特性及火焰加工性能对比试验

针对我国火焰加工方面形成的单一能源结构方式，选用丙烷，丙烯、液化石油气，乙炔等四种燃气进行了基本特性比较和热切割、火焰校正等加工性能的对比试验，并根据各种燃气燃烧特性的不同．选择了合理优质工具。对每种燃气的经济性和社会效益进行了分析，指出将丙烷用于上述火焰加工具有突出的经济性，安全性及较高的质量保证。     

氧乙醇汽油火焰燃烧分析及切割试验

根据热力学理论,通过分析氧乙醇汽油的燃烧过程、各区域的产热及其能量平衡关系,计算了乙醇在不同混合比例下的火焰燃烧理论温度.根据当前国内车用乙醇汽油的实际应用情况,提出了利用氧乙醇汽油火焰切割金属的新方法.利用专用割嘴进行一系列切割试验后表明,氧乙醇汽油在乙醇比例为10％～50％范国内火焰燃烧稳定,能满足普通钢材的火焰切割要求,通过在辽宁石油化工大学本科生实践教学的应用,证明切割质量优良,具有很好的节能性和安全性.     

可燃气体在钢管公司应用的前景

国内用液化石油气进行焊接和切割始于 70年代,因种种原因没有很好推广应用, 90年代切割用乙炔燃气仍占 90％左右,基本属单一燃气能源结构。而日本 80年代初,液化石油气用量已达到总用气量的 61％。我国石油资源丰富,开发利用石油化工的副产品作为焊接和切割燃气具有广阔的前景。 丙烯、丙烷、液化石油气均是石油化工的副产品,属于碳氢化合物,化学性质不活泼。其燃点高,燃烧速度慢,爆炸极限范围小,不易产生回火爆炸。对于压力、温度、冲击等敏感度比乙炔低,用于火焰加工是比较安全的。使用烷烃气、液化石油气、天然气是世界工业燃气发展的方向,现在这类气体约占燃气消耗总量的 65％,乙炔仅占 35％。随着人类对环境保护意识的加强,使用“绿色燃气”的趋势逐渐增强。     

氧生物柴油火焰温度计算及火焰切割分析

从理论上分析生物柴油用于金属火焰切割的可行性,根据热力学理论计算生物柴油中性焰和氧化焰的理论温度,分析生物柴油燃烧过程中氧气的消耗量;并根据燃烧学对比分析生物柴油与汽油在空气中完全燃烧的火焰长度。计算结果表明:虽然生物柴油火焰温度比乙炔燃烧温度低,但能达到2436℃以上,火焰长度将近是汽油火焰长度的0.92倍,长度基本相当,说明生物柴油可用于金属火焰切割,只是预热时间应比乙炔长。这在理论上说明生物柴油可作为金属切割的燃料,为进一步进行氧生物柴油火焰切割技术研究奠定了理论基础。     

燃焰法沉积金刚石薄膜涂层刀具时的生长均匀性研究

在分析燃焰法民金刚石机理的基础上,研究了用燃焰法在刀具上沉积金刚石薄膜时的生长均匀性问题,提出了刀刃上金刚石的异常生长原因及抑制方法,获得了涂层均匀的金刚石薄膜涂层刀具。     

套筒式陶瓷燃烧器内燃烧过程数学模型

应用湍流扩散火焰燃烧模型，对套筒式陶瓷燃烧器燃烧室内的燃烧过程进行了计算机模拟研究，确定了燃烧过程中煤气空气及燃烧产物的速度分布，温度２和各组分的浓度分布，得到了燃烧过程中火焰的形状和长度。     

Analysis and influence of acetylene and propane gas during oxyfuel gas cutting of 1045 carbon steel

Many metal-manufacturing industries include oxyfuel cutting among their manufacturing processes because cutting and welding are often required in metal-cutting processes, specifically in the fabrication of pressure vessels and storage tanks. The oxyfuel cutting process uses controlled chemical reactions to remove preheated metal by rapid oxidation in a stream of pure oxygen. Previous research has demonstrated that metal cutting surfaces varied depending on the gas used for the combustion as well as the cutting speed (Vc) used during the process. In this research, AISI 1045 carbon steel was cut using an oxyacetylene and an oxypropane cutting process. Different tests, such as surface roughness, cut drag displacement, groove width, microhardness, and microstructure, were used to analyze the influence of the Vc and the combustion flame (oxyacetylene and oxypropane). The results showed, in general, better cut surfaces when using propane gas. Also, it was demonstrated that oxyacetylene cutting is almost 85% more expensive than oxypropane cutting.     

Simulation and application of a HVOF process for MCrAIY thermal spraying

This work deals with numerical simulation and application of a high velocity oxygen fuel (HVOF) process for MCrAlY thermal spraying. The main objective of this study was to observe the correlations between coating oxidation and oxygen content in combustion products or flame temperature. Spray parameters were selected on the basis of the numerical simulation of combustion and particle behavior in the flame. The results of experiments revealed that the oxygen content is not the main key factor concerning the oxidation rate of MCrAlY coatings. On the contrary, the flame temperature has a decisive influence on oxidation. Combustion conditions corresponding to stoichiometric factors between 0.82 and 1.2 appeared not to be favorable for MCrAlY thermal spraying. Outside this range, it appeared preferable to use a combustion system on the fuel-rich side.     

High-Velocity Suspension Flame Spraying (HVSFS), a new approach for spraying nanoparticles with hypersonic speed

The fabrication of nanostructured coatings by means of thermal spray techniques is a challenging approach with new applications in mind. However, it requires the processing of very fine-grained powders with a grain size in the nanoscale. As nano- and submicrometer powders cannot be processed using mechanical powder feeders, new concepts have to be developed. Among these, suspension spraying is one of the most promising.High-velocity suspension flame spraying (HVSFS) is a new approach to spray micron, submicron or nanoparticles with hypersonic speed with the aim to form thin and dense coating layers. For this purpose, the powder is dispersed in aqueous or organic solvent and fed axially into the combustion chamber of a modified High-Velocity Oxyfuel (HVOF) spray torch. Several suspension feeder concepts were tested to ensure a constant flow of the suspension and, thus, a stable spray process.Different oxide materials were processed in form of a suspension containing submicrometer- or nanosized powders consisting of alumina, titania and yttrium stabilized zirconia (YSZ). The paper gives an introduction to HVSFS technology and will present first experimental results.     

液体燃料-空气/氧气混合助燃超音速火焰喷涂枪的研制

采用枪内混气方式,设计研制了一种采用炽热体作为稳焰器的液体燃料-空气/氧气混合助燃超音速火焰喷涂枪.用SprayWatch热喷涂监测系统测试喷涂枪焰流出口速度和温度,并研究喷涂工艺对WC-12Co涂层组织和性能的影响.结果表明,喷涂枪焰流出口速度超过1300m/s,焰流温度可在2302～3410K之间进行精确调节,精度达到±50K;提高空气/氧气比,涂层中WC保留率明显提高,使涂层硬度比氧气助燃时得到明显提高;采用空气助燃进行喷涂,可以得到厚度超过5mm的WC-12Co涂层.     

Modelling and analysis of abrasive water jet cut surface topography

In this paper, a new approach proposed for modelling the three-dimensional (3D) topography produced on abrasive water jet (AWJ) cut surface is presented. It makes use of the trajectory of jet, predicted from the theory of ballistics and Bitter’s theory of erosion for material removal, for numerically simulating the cutting front. The 2D topography at different depths of the cut surface is generated by considering the trajectories on the cutting front and the abrasive particles impacting the walls of cut surface randomly. For realistic generation of topography on cut surfaces, several instantaneous profiles generated in each region of cut are superimposed to obtain an effective profile. The nature of effective profiles thus predicted is analyzed and validated using power spectral density analysis. The effective profiles predicted at different depths are in turn used to generate the 3D topography of AWJ cut surface. Results obtained with the proposed model are validated with the experimental results.     

聚硅氧烷的结构对其阻燃性能的影响

研究了聚硅氧烷的苯基侧基含量及有机基团与Si原子的摩尔比(即R/Si)对其阻燃性能的影响,考察和分析了聚碳酸酯(PC)/聚硅氧烷阻燃体系的燃烧行为和炭层形貌。结果表明,苯基含量对聚硅氧烷的阻燃性能影响较大,苯基质量分数75%时聚硅氧烷阻燃性能最好,支链聚硅氧烷的阻燃性能优于线形聚硅氧烷。与PC相比,PC/聚硅氧烷在燃烧时能形成较为均匀、致密,质地坚硬的炭层,正是由于这一含硅炭层起到了良好绝缘保护层的作用,从而有效地提高了PC的阻燃性能。