浅谈模锻和精锻叶片的冷加工技术

本文通过例举模锻和精锻叶片在冷加工中几个难度较大的工序,阐明了这两种锻件在生产中的相互关系及它们不同的加工方法。最后,论证了在我国现有技术和设备能力下,大中型叶片的精锻件必将代替模锻件。     

燃气-蒸汽联合循环汽轮机2Crl3扭叶片模锻件 毛坯生产工艺流程及质量控制要点

汽轮机叶片是汽轮机的心脏，其叶片的制造技术和制造质量直接影响机组的运行性能和可靠性，特 别是叶片原材料质量、锻造和热处理生产过程质量严重影响着叶片的抗拉强度、疲劳强度及使用寿命，所以 说控制叶片模锻件设计质量、原材料质量及锻造、热处理过程质量至关重要。本文仅从某型号燃气-蒸汽联合 循环汽轮机2D13扭叶片生产过程对最终产品质量的影响进行分析，阐明生产过程中不同工艺因素对叶片最 终质量的影响，并明确其控制措施，进而提高2D13扭叶片实物质量，防止在叶片生产过程中出现批次报废或 在使用过程中出现失效等严重故障，达到提高生产效率和降低质量损失的目的。     

蜡模制造后掠式压气机叶轮

后掠式压气机叶轮形状复杂,特别是叶片翘曲角大于20度时,给叶轮的制造工艺增添了许多不便。用失蜡铸造方法制造,阴模压进蜡后,模块被蜡质叶轮叶片勾住,很难取出。为了克服这一困难,采用了柔性模,即以硅橡胶模代替蜡模,以石膏模代替硅酸乙酯涂料制的壳型的工艺。柔性模最大优点是不必耽心模块被叶片勾住,拆模时,勾住的叶片部位在外力作用下随着力的方向产生变形,当型块取出后,它能恢复到原状。另外,做出的硅橡胶叶轮,可以重复使用数次。但是柔性模制造叶轮的工艺方法,与失蜡精密铸造制     

1500r/min核电汽轮机71英寸末级叶片的研发

简要介绍了哈汽公司1500r/min核电汽轮机71英寸末级叶片在气动、结构和频率特性等方面的设计思路,特别介绍了遵循叶片模化设计相似准则由1500r/min71英寸叶片模化设计的3000 r/min35.5英寸叶片的运行业绩,由此证明了1500r/min71英寸叶片的安全可靠性。     

燃气轮机透平叶片国产化需解决的关键技术问题

透平叶片是重型燃气轮机的核心部件,实现透平叶片的国产化有着巨大的社会效益和经济效益。但由于历史原因,我国尚未掌握透平叶片的设计和制造技术。本文探讨了透平叶片国产化过程中所需解决的若干关键技术问题,涉及到逆向工程设计,包括:高温合金及涂层等基础材料;气动、传热、结构、强度等多学科交叉分析和优化;精密铸造、特种加工、涂层制备等多种精密加工工艺。研究表明,要实现透平叶片的国产化,需要通过严谨的逆向工程设计才能降低国产化过程中的技术风险,更需要国内在材料—设计—制造—试验等各个环节的企事业单位和科研院所共同合作。     

1050mm汽轮机钛合金叶片的研制

采用优化的模锻工艺参数,完成了1050 mm汽轮机末级TC4钛合金叶片的锻造。锻件的机械性能及微观组织试验研究结果表明,锻件的性能满足技术要求,1050 mm汽轮机末级钛合金叶片的研制取得了成功。     

从阀盖锻件产生折迭看滚压模膛设计

通过对高压阀门上阀盖零件产生折迭的试验与研究 ,分析锻件上产生折迭的原因 ,确定新滚压模膛的设计方案 ,杜绝了折迭的产生 ,保证锻件质量。     

提高连杆模锻件质量的试验研究

本文就如何提高柴油机连杆模锻件质量、降低废品率、提高材料利用率等问题进行了探讨。提出采用“大圆弧”杆身截面代替“工字形”杆身截面、取消预锻模膛、采用新颖方法设计制坯模膛、毛坯喷丸强化处理等措施,并提供了一些可供借鉴的经验。     

三缸二排汽廿万千瓦汽轮机低压通流部份叶片的设计

本文论述了哈尔滨汽轮机厂三缸二排汽廿万千瓦汽轮机低压通流部份叶片的设计特点。着重说明了大刚性高效率动叶片的设计和大出汽角、高马赫数、高效静叶片的设计。还从理论上分析了末级叶片在低负荷运行下的特点、设计原则以及叶片模化设计的原理。     

叶片锻件精度评定标准的改进

本文介绍了一种新的叶片锻件精度评定方法,采用该方法可以合理地确定模锻叶片的加工含量,减少检验工作量,同时也适合精锻叶片的生产。     

Estimation of heat transfer coefficient of forced-air cooling and its experimental validation in controlled processing of forgings

Estimation of the cooling efficiency of an accelerated air for the needs of cooling of die forgings is presented. Temperature dependence of heat transfer coefficient (HTC) was calculated for different cooling conditions varied by airflow velocity, covering the range from 18 to 48?m/s. Time–temperature measurements performed on a full-scale semi-industrial cooling line provided similarity to conditions typical of industrial conveyor, which gives the results utilitarian significance in design of controlled processing (of steel forged products). Acquired HTC values, ranging from 164.7 to 298?W/m²?·?K, were validated in numerical simulation of cooling complex-shape forgings and subject to experimental verification, indicating perfect agreement with physical measurements.     

New response surface model and its applications in aerodynamic optimization of axial compressor blade profile

A parametric method for the axial compressor 2D blade profiles is proposed in which the blade geometries are defined with the parameters commonly used for blade definition, which ensures that the geometric significance is clear and an unreasonable blade profile is not generated. Several illustrations are presented to show the fitting precision of the method. A novel response surface model is proposed which regards the objective distribution function in the vicinity of a sample as normal school, and then generates the response surface function in the whole design space by a linear combination of distribution functions of all the samples. Based on this model, a numerical aerodynamic optimization platform for the axial compressor 2D blade profiles is developed, by which aerodynamic optimization of two compressor blade profiles are presented.     

基于KBE叶片快速设计方法的研究与实现

复杂产品设计过程是不断迭代反复的过程。为解决汽轮机叶片设计效率低,从汽轮机叶片结构及设计过程出发,定义叶片设计过程向导;提供自动处理叶片型线方法,实现叶身的快速设计;根据叶片结构特点,采用特征设计技术,快速定义叶根、拉筋、围带;基于动静叶片依赖关系,实现动静叶片之间、叶身、叶根、中间体之间的相关性设计;按照叶片设计中气动、强度要求,实现叶片设计与分析的自动优化。以汽轮机某型号叶片为例,在自行开发的叶片快速设计系统上验证本文提出的方法,结果表明,叶片设计效率得到很大的提高,提出的叶片快速设计方法有效可行。     

A review and design study of blade testing systems for utility-scale wind turbines

Since the blades are one of the most critical components of a wind turbine, representative samples must be experimentally tested in order to ensure that the actual performance of the blades is consistent with their specifications. In particular, it must be demonstrated that the blade can withstand both the ultimate loads and the fatigue loads to which the blade is expected to be subjected during its design service life. In general, there are basically two types of blade testing: static testing and fatigue (or dynamic) testing. This paper includes a summary review of different utility-scale wind turbine blade testing methods and the initial design study of a novel concept for tri-axial testing of large wind turbine blades. This new design is based on a blade testing method that excites the blade in flap-wise and edgewise direction simultaneously. The flap motion of the blade is caused by a dual-axis blade resonance excitation system (BREX). Edgewise motion is delivered by the use of two inclined hydraulic actuators and linear guide rail system is used to move the inclined actuators in the flap-wise direction along the blade motion. The hydraulic system and linear guide rail requirements are analyzed and an initial cost estimate of the proposed system is presented. Recommendations for future work on this proposed system are given in the final section of this work.     

微型水轮机复合雨水发电装置的流场数值模拟研究

微型水轮机是简易复合水力发电设备的核心装置.为了更好设计微型水轮机的叶片,本文采用VOF（Volume of Fluid）模型对其进行了数值模拟计算,通过与实际情况的对比分析,验证模拟的正确性,并分析了在不同的转数、不同的叶形条件下流场特性的差异,选择了合适的叶形.本文的研究对装置的设计有一定的指导意义.     

New response surface model and its applications in aerodynamic optimization of axial compressor blade profile

A parametric method for the axial compressor 2D blade profiles is proposed in which the blade geometries are defined with the parameters commonly used for blade definition, which ensures that the geometric significance is clear and an unreasonable blade profile is not generated. Several illustrations are presented to show the fitting precision of the method. A novel response surface model is proposed which regards the objective distribution function in the vicinity of a sample as normal school, and then generates the response surface function in the whole design space by a linear combination of distribution functions of all the samples. Based on this model, a numerical aerodynamic optimization platform for the axial compressor 2D blade profiles is developed, by which aerodynamic optimization of two compressor blade profiles are presented. __________ Translated from Acta Aeronautica et Astronautica Sinica, 2007, 28(4): 813–820 [译自: 航空学报]     

三代非能动核电项目SA-508国产大锻件性能不符合项探讨

三代非能动核电项目RPV和SG用SA-508 Gr.3 C．1和SA-508 Gr.3 Cl.2锻件设计要求严格,制造难度高,在国产化制造过程中出现了诸多的性能不符合项。定量比较了三代非能动核电项目RPV和SG用SA-508锻件的设计要求与ASME规范要求的差异,并统计分析了RPV和SG用SA-508锻件的力学性能实测值。结果表明,RPV用SA-508 Gr.3 C．1锻件的不符合项的主要原因是低温韧性不足,SG用SA-508 Gr.3 C．2锻件的不符合项的主要原因是低温韧性、室温和高温抗拉强度。最后研究了RPV和SG用SA-508锻件化学成分和热处理工艺特点,分析了造成国产化大锻件性能不稳定的原因。为克服SA-508大锻件的制造现状与设计要求的矛盾,亟需对大锻件生产工艺进行优化或采用新型的制造工艺进一步提升大型锻件的性能。     

离心泵叶轮扭曲叶片参数化实体造型研究

扭曲叶片作为离心泵的重要部件,其制作过程及精确程度是影响离心泵性能的重要因素。本文借助Pro/E造型平台,依据二维木模图来表达叶轮模型,提出了叶轮轴面投影及水力木模图的测绘方法,然后将叶片的数据导入造型软件并生成叶轮的实体造型,实现了离心叶轮的参数化设计,实例计算结果表明,提出的理论和方法是有效的,能够实现叶轮的快速高效设计。此方法生成的文件为进一步的叶轮流场数值模拟软件fluent、Ansys等仿真软件分析提供了接口文件。     

水平轴风力机桨叶的实验模态分析

桨叶的模态分析是风力机整机稳定性及其可靠性分析的重要基础。该文应用DAS动态信号分析与故障诊断系统,对水平轴风力机的桨叶进行了实验模态研究。通过测量分析桨叶的振动信号,得到桨叶的模态,为理论分析计算风力机桨叶与整机模态的算法选择和修正提供了依据。同时对在模态实验中的参数识别和精度提高等问题进行了探讨。