实用技术与工艺装备

电感活塞环高度测微仪　　活塞环是内燃机中最为常用的零件 ,活塞环高度是影响其质量的重要因素之一 ,目前我国多数工厂在检测活塞环高度时用千分尺手工测量。测量速度慢、误差大 ,难以适应现代化生产的需要。为此 ,我们自制了电感测微仪 ,在活塞环生产过程中用于其高度检测 ,取得了很好的效果。图 1　电感测微仪结构示意图电感活塞环高度测微仪结构如图 1所示。使用时 ,松开螺钉1 ,转动滚花手柄 ,使上测头 A与下测头 B对准后拧紧螺钉 1。这是启用测微仪前的调整 ,一旦调整好 ,以后就不必再作调整。置功能开关于“B”,用一块规作为活塞环…     

打火机火焰高度自动测量研究

介绍CCD数字成像技术在打火机火焰高度自动测量中的应用，该测试装置能对燃烧火焰的高度、突跳、爆火等现象，采用自动瞬时捕获、采样、成像、显示、结果判定、数据输出等功能，使打火机燃烧高度测量变得方便、快捷、准确可靠。     

装配流水线的优化设计

在大批量生产的工厂中,根据生产纲领而采用了与之相适应的各种装配流水线。为提高装配流水线的生产效率和技术经济效益,必须合理组织生产环节,使装配过程具有良好的连续性、高度的均衡性和严格的节凑性。因此对装配流水线的均衡设计,运行中变化因素对均衡性的影响和动态调整是设计中应注意解决的问题。     

渗碳炉加装火焰罩

气体滲碳炉工作时,废气要点燃,并可根据火焰的颜色、高度来判断炉内状况。由于车间和炉子上方冷热空气紊流,使火苗倒向一方而不垂直上升,这对观察火苗高度不利。为此我们在排气口加装一玻璃罩,这样火苗基本上是垂直上升。为使火苗的高度不因     

抽油杆直线度的测量及生产控制

结合实际生产中遇到的问题,以抽油杆直线度的测量及生产控制为切入点,详细分析了API 11B规范中对抽油杆直线度的测量要求。同时结合本厂的实际生产情况,针对抽油杆直线度不达标质量问题设计了大平台的全跳动检测设备。除此之外,为确保抽油杆能满足更为严格的直线度要求,对抽油杆的整个生产工艺过程做了一些改善或者优化,实际效果证实这些措施都是很有成效的。     

圆锥滚子轴承内外端面高度差测量方法的改进

<正>1引言我公司生产的单列圆锥滚子轴承,外径尺寸在100-210不等。某主机用户对此类轴承有一项特殊要求:内外端面高度差,其尺寸偏差精度控制在±0.05mm。为此,调整磨削加工工艺,并在装配后全部加以检测,以确保达到客户需求。测量时,在G904、G905、G906高度仪上分两次测量(装配高和内圈高度的尺寸测量),两者的差即为高度差。高     

甲烷浓度与沼气检漏报警一体化测试仪的研制

针对沼气生产过程中进行相关参数的测试功能,研究一种集甲烷浓度检测与泄漏检测于一体的组合测量装置设计方案,说明了产品设计过程中的安全方案,讨论了所采用的两种传感器的性能与测量方法,分析了测量与转换电路的工作过程,给出一种零点调整与设备标定的方法.     

挤方冲头尺寸的专用检具

在生产挤方冲头的过程中，我们常常遇到这样的问题：如图1所示尺寸d1的测量。在加工d1的过程中，因为d1与d2的尺寸较小(见表1)，工序中的测量比较繁琐，每次磨好砂轮，调整磨床，对好尺寸后，就需去计量室检测；假若尺寸不合理，须再调整一遍，然后再检测。     

微粉粒度检测系统的设计

传统的沉降式微粉粒度检测仪器易受人为因素和环境因素的干扰,导致测量结果失真.为了提高测量结果的准确性和可重复性,在样品颗粒的沉降过程中,利用光强传感器和温度传感器测量出不同时刻的沉积高度和环境温度,通过对采集的高度、温度等数据进行动态分析,最终得出被测样品的粒度分布.系统实现了微分粒度的自动化检测,为后续的生产加工提供了有力保障.     

液位变送器安装方式对水位测量精度的影响

火力发电厂的凝汽器水位、除氧器水位、汽包水位、高低加水位等等,在生产过程中都必须进行严格监视和调整。水位测量准确与否,直接关系到水位的自动调整和准确保护设备。目前使用的水位测量变送器大部分是智能型,技术比较成熟,测量精度高,但传统的安装方式却使液位测量存在诸多弊端,给设备的安全经济运行造成不利影响,为此,对液位测量变送器的安装方式应予以探讨和改进。 1.变送器测量水位的原理 变送器是一个很广泛的名词,从词义上理解就是“转变、传送的仪器”。在工业生产中,变送器的作用是将被测介质的物理过程量,转变为标准电量     

基于仿真分析的船用防爆阀阻燃片优化研究

针对防爆阀阻燃片结构设计缺少理论指导,主要依靠实验测试完成设计的问题,给出了一种仿真分析方法,以便于结构优化研究。借助计算流体力学理论和FLUENT仿真平台,建立了阻燃片的优化模型,通过均匀设计方法对阻燃片凸台宽度、凸台角、凸台高度等尺寸数据进行了分析,使用MATLAB对仿真数据进行了回归处理,通过出口总压与温度的散点图寻找性能最佳尺寸。研究结果表明,运用均匀设计和回归分析数值处理方法有利于数据处理和多目标优化,获得的尺寸回归函数能求得性能最佳尺寸;仿真结果与实际情况基本一致,同时该尺寸阻燃片实际测试过程中降压灭焰性能满足要求,有助于防爆阀阻燃片的设计研究。     

Prediction of flame formation in highly preheated air combustion

Fundamental information about the ignition position and shape of a flame in highly preheated air combustion was obtained, and the suitability of the suggested reduced kinetic mechanism that reflects the characteristics of the highly preheated air combustion was demonstrated. Flame lift height and flame length with variations of premixed air temperature and oxygen concentration were measured by CH* chemiluminescence intensity, and were computed with a reduced kinetic mechanism. Flame attached near a fuel nozzle started to lift when preheated air temperature became close to auto-ignition temperature and/or oxygen concentration reduced. The flame lift height increased but the flame length decreased with decreasing preheated air temperature and flame length reversed after a minimum value. Calculated results showed good agreement with those of experiment within tolerable error. Flame shape shifted from diffusion flame shape to partial premixed flame shape with increasing lift height and this tendency was also observed in the computation results. This paper was recommended for publication in revised form by Associate Editor Ohchae Kwon Gyung-Min Choi studied the areas of combustion engineering, heat recirculating combustion, and solid fuel gasification, receiving his Ph.D. degree in engineering from Osaka University in 2001. He served as a researcher at Japan Aerospace Exploration Agency and is now an associate professor in the School of Mechanical Engineering at Pusan National University.     

Effect of streamwise and preferential diffusion on cylindrical Burke-Schumann flames

Effect of streamwise and preferential diffusion on cylindrical Burke-Schumann flame has been analyzed using perturbation method and Green’s function technique. Results show that for large Peclet number, streamwise diffusion has little effect, while for small Pe, it is balanced with radial diffusion such that a finite minimum flame height exists. Preferential diffusion induces flame temperature variation along the flame surface and the results agree qualitatively with existing experimental data. It also shows that the symmetry in flame temperature variation by the sign of (Le-1) in two dimensional case does not hold in cylindrical flames due to focusing and defocusing effects of mass and thermal diffusion by the radial curvature of flame.     

Effects of propane pyrolysis on basic flame structures of non-premixed jet flame

Recently, high temperature combustion techniques have been extensively adopted to improve thermal efficiency of combustion devices. When the temperature is sufficiently high, fuel pyrolysis may occur and then the flame structure can be affected. Thus, the understanding flame structure at high temperature coupled with fuel pyrolysis is essential to design burners operated in high temperature environments. In this study, propane was heated up to 1100 K using an electric heater, and the characteristics of fuel pyrolysis and its effects on non-premixed jet flames were experimentally investigated at room temperature. Normalized volume flow rates and components were measured regarding the fuel pyrolysis. The normalized volume flow rates of the propane were increased significantly through the pyrolysis process, and they agreed with numerical results based on an ordinary chemical mechanism. Variations of flame height and soot region were compared for the pyrolysis temperature. Conclusively, in spite of the significant growth in the volume flow rate by the propane pyrolysis, flame height was not significantly affected. On the contrary, the soot region was slightly extended by the fuel pyrolysis. This study will help to extend understanding on jet flame characteristics especially at high temperature conditions.     

高门架堆垛叉车载荷稳定性分析

对叉车常用堆垛高度进行稳定性试验,得出粗略载荷曲线。稳定系数法不能真实反映叉车稳定载荷情况,且叉车受载后货物质心发生变化对载荷稳定性有影响。采用质心法对叉车稳定性载荷进行研究,同时综合考虑叉车门架受载变形、多级门架移动副配合间隙、滚轮与叉车门架槽钢接触变形、货物质心偏载等因素对叉车稳定载荷的影响。以诺力机械股份有限公司某型号堆垛叉车为例,求出其载荷曲线,并通过稳定试验验证其正确。     

单箱梁岸边集装箱起重机自行式小车总成轻型结构形式

由于岸边集装箱桥式起重机的速度不断高速化,外伸距及起升高度的不断增加,吊具下额定起重量不断增大,要求运行小车自重越来越轻。文中所介绍的单箱梁自行式小车,通过对其结构及机构的优化设计,使其质量大为减小,制造和使用成本大为节约,符合节能减排环保经济的发展方向。这些优点加之新技术,都将提高产品的综合竞争力。     

基于数字图象处理的火焰轮廓提取方法研究

在分析测试原理的基础上,提出了一种基于数字图像处理学的火焰轮廓的提取方法。该方法利用彩色面阵CCD相机获取火焰图像,提出一种依据火焰图像三原色的灰度分布关系提取火焰轮廓的数字化方法。通过相应的算法对图像进行了直方图均衡化、二值化、区域填充、图像滤波等处理,最终通过形态学提取了火焰轮廓,剔除了烟雾、火星和标尺的干扰,将火焰尾迹与烟雾区进行了有效的分离。利用Matlab进行编程,通过试验验证。该方法代替了传统人工观测,提高了测试精度。     

Wear behaviour of flame sprayed NiCrBSi coating remelted by flame or by laser

Flame spray coatings are widely used in industry because of low cost and process simplicity. However, high porosity and poor adherence to the substrate means that quality is poor, though it can nevertheless be improved by subjecting coatings to a remelting using a technique that usually involves an oxyacetylene flame. The study that follows is an attempt to evaluate a laser technique as an alternative to the more traditional flame remelting of flame spray layers, using grey cast iron (DIN GG30) as the substrate and a NiCrBSi alloy as the coating material. Coatings obtained by laser remelting exhibited a practically pore-free microstructure with good adherence to the substrate. The limited control of process parameters during flame remelting led in some cases to incomplete melting of the full thickness of the layers. Hardness of the remelted coatings was very similar in both cases, with values that were slightly lower than for flame-spray layers. The tribological behaviour of both coating types was then compared in dry sliding wear tests (block-on-ring tests) at various loads (30–100 N) and sliding speeds (0.65–2.62 m/s). Both coatings wear rates and wear rate coefficients k (mm³/Nm) were calculated. No significant differences in wear performance between the two coatings were found. A severe wear regime with adhesion as the principal component was observed at the higher test loads. The predominant wear mechanism at the lower test velocities was oxidation.     

Investigation of a flame holder geometry effect on flame structure in non-premixed combustion

In this paper the effect of flame holder geometry on flame structure is studied. The obtained numerical results using realizable k-? and β-PDF models show a good agreement with experimental data. The results show that increasing in flame holder length decreases flame length and increases flame temperature. Additionally, it is observed that flame lengths decrease by increasing in flame holder radius and increase for larger radii. Furthermore in various radii, the flame temperature is higher for smaller flame lengths. It was found that behavior of flame structure is mainly affected by the mass flow rate of hot gases that come near the reactant by the recirculation zone.     

塔架法兰焊接缺陷的火焰矫正方法

塔架法兰与筒节焊接后,如果平面度或内倾度超标,可以通过火焰矫正的方法进行修复。采用火焰矫正方法时,火焰温度、加热位置等因素都会影响最终的矫正效果。论述了火焰矫正方法的原理,介绍了火焰矫正工艺流程,有助于提高火焰矫正的成功率。