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1.
2000m^3在役压力容器应力状况分析   总被引:2,自引:0,他引:2  
本文报道了钢制2000m^3球罐实际运行一年后的应力状况,对球罐的残余应力及工作应力进行了现场测试,发现球罐虽经过整体热处理,但局部残余应力仍较高等问题,并进行了对比分析。  相似文献   

2.
本文报道了钢制 2 0 0 0 m3球罐实际运行一年后的应力状况 ,对球罐的残余应力及工作应力进行了现场测试 ,发现球罐虽经过整体热处理 ,但局部残余应力仍较高等问题 ,并进行了对比分析 .  相似文献   

3.
无损电测解析法测定焊接容器的残余应力   总被引:1,自引:1,他引:1  
张亦良  程咏梅 《实验力学》1994,9(4):367-375
本文从塑性增量理论出发,论述了无损电测解析法的基本原理和应用此法确定残余应力的基本步骤,并将其应用大型球罐的现场测量。其特点是在容器例行的水压试验中只需应用电阻应变片测量应变即可确定残余应力用此法所得结果同盲孔法所得结果进行了对比。表明具有一定的工程精度。  相似文献   

4.
云纹干涉与钻孔法测量残余应力的实验方法与系统   总被引:7,自引:0,他引:7  
戴福隆  亚敏  谢惠民  吕坚 《实验力学》2003,18(3):313-318
应变片钻孔法是工程中应用最广的残余应力测量方法之一,由于应变片只能得到其长度范围内的平均应变,测量误差比较大,本文提出用云纹干涉法测量的位移信息代替应变片测量的应变信息来确定残余应力,用有限元建立位移与残余应力之间的关系,基于以上理论,开发了一种可以进行现场残余应力测量的便携式云纹干涉钻孔系统,并用该仪器进行了铝合金激光焊接接头的残余应力测量,得到了焊缝中心残余应力值。  相似文献   

5.
高压聚乙烯装置用G4345V钢厚壁管冷弯残余应力检测   总被引:1,自引:0,他引:1  
谢大吉  冯长波 《实验力学》1997,12(4):520-526
本文对某厂聚乙烯装置用G4345V钢厚壁管冷弯残余应力进行了检测.为寻求较适用的降低残余应力的方法,对弯管进行两种处理以后的效果进行了检验,二种处理工艺为热处理(370℃)及喷丸.最后在现场对喷丸前后的残余应力用磁各向异性探头进行了检测,证明该方法有很大的发展前途  相似文献   

6.
激光反射全息干涉法现场测量残余应力的实验研究   总被引:1,自引:0,他引:1  
本文根据激光反射干涉法的基本原理,采用钻盲孔释放残余应变的手段,提出一种新颖的残余应力激光全息现场测量的方法,推导出该光学测量方法3种计算公式.解决了激光全息干涉法不能进行现场实测的难题.  相似文献   

7.
本文根据激光反射干涉法的基本原理,采用钻盲孔释放残余应变的手段,提出一种新颖的残余应力激光全息现场测量的方法,推导出该光学测量方法3种计算公式.解决了激光全息干涉法不能进行现场实测的难题.  相似文献   

8.
15万立米气柜残余应力及工作应力测试分析   总被引:4,自引:2,他引:4  
张亦良  徐学东 《实验力学》1998,13(3):343-348
报导了15万立米大型煤气气柜挂圈走台的残余应力及气柜升降时工作应力的测试结果。该气柜服役十余年后发生煤气泄漏,为分析其原因,进行了残余应力及气柜修复前后的工作应力测试,结果表明:修复前残余应力及工作应力均达到很高水平,气柜升起时伴有严重侧偏现象,修复后应力状态有明显好转。  相似文献   

9.
压力机焊接残余应力的状态分析   总被引:2,自引:0,他引:2  
张亦良  徐学东 《实验力学》1999,14(3):341-346
对 2000k N 及 1500k N 压力机焊后残余应力状态进行了测试分析,并对用振动法和热处理两种方法进行消除残余应力的效果进行了现场测试及对比分析。  相似文献   

10.
许金泉  金烈候 《力学季刊》1996,17(3):189-195
接合残余应力对异种接合材料强度的影响很大,正确地分析接合残余应力在界面端附近的分布及其奇异特性,是研究异材强度评价方法的关键问题之一,本文利用弹性学中的Goursat公式和有关微分方程解的理论,求得了平面近似下的界面端附近的残余应力场及其应力奇异性,与单纯的外力作用时的情况不同,残余应力在界面端有可能出现对数型的应力奇异性,并且不能仅用Dunders的异材参数来描述。  相似文献   

11.
再生器、沉降器残余应力状态分析   总被引:3,自引:1,他引:2  
对炼油厂催化系统的再生器、沉降器残余应力状态进行现场测试分析,并对出现缺陷处、装置焊接成型过程中的强力组装处等典型部位进行测试,分析了出现缺陷的原因。  相似文献   

12.
高速客车转向架残余应力的试验研究   总被引:6,自引:0,他引:6  
李强  刘志明 《实验力学》1999,14(2):260-266
利用磁弹性这种新型的无损检测方法对高速客车转向架焊接构架组焊后的残余应力和构架在疲劳试验过程中的残余应力进行了试验研究,得到了构架残余应力随循环周次的变化规律  相似文献   

13.
应用干涉云纹测量工艺应力分布   总被引:5,自引:0,他引:5  
本文就冷胀孔周残余应力分布的测量技术和干涉螺接孔周干涉应力分布的测量技术进行了实验研究。沿着径向将试件切割,以释放欲测的应力,同时用干涉云纹技术测量由于释放应力而引起的附加应变场。文中还就残余应力在循环载荷作用下的松弛问题进行了实验研究。提供了典型的实验结果,讨论了引起实验误差的主要原因。  相似文献   

14.
本文用夹层全息干涉法做了模拟残余应力的标定实验,测试了焊缝、铸件的残余应力,并且利用数值方法进行了定量分析,实验结果与理论值比较吻合。  相似文献   

15.
Mechanical strain relief techniques for estimating the magnitude of residual stress work by measuring strains or displacements when part of the component is machined away. The underlying assumption is that such strain or displacement changes result from elastic unloading. Unfortunately, in components containing high levels of residual stress, elastic-plastic unloading may well occur, particularly when the residual stresses are highly triaxial. This paper examines the performance of one mechanical strain relief technique particularly suitable for large section components, the deep hole drilling (DHD) technique. The magnitude of error is calculated for different magnitudes of residual stress and can be substantial for residual stress states close to yield. A modification to the technique is described to allow large magnitudes of residual stress to be measured correctly. The new technique is validated using the case of a quenched cylinder where use of the standard DHD technique leads to unacceptable error. The measured residual stresses using the new technique are compared with the results obtained using the neutron diffraction technique and are shown to be in excellent agreement.  相似文献   

16.
Shear stresses along the shaft/hub interface in shrink-fit components, generated by torsional loads, can drive premature failure through fretting mechanisms. It is difficult to numerically predict these shear stresses, and the associated circumferential slip along the shaft/hub interface, due to uncertainties in frictional behaviour and the presence of steep stress gradients which can cause meshing problems. This paper attempts to provide validation of a numerical modelling methodology, based on finite element analysis, so the procedure may be used with confidence in fitness-for-purpose cases. Very few experimental techniques offer the potential to make measurements of stress and residual stress interior to metallic components. Even fewer techniques provide the possibility of measuring shear stresses. This paper reports the results of neutron diffraction measurements of shear stress and residual shear stress in a bespoke test specimen containing a shrink-fit. One set of measurements was made with a torsional load ‘locked-in’. A second set of measurements was made to determine the residual shear stress when the torsional load had been applied and removed. Overall, measurement results were consistent with numerical models, but the necessity for a small test specimen to allow penetration of the neutron beam to the measurement locations meant the magnitude of shear stresses was at the limits of what could be measured experimentally.  相似文献   

17.
The present study deals with the development and the application of the through-hole drilling method for the residual stress analysis in orthotropic materials. Through a systematic theoretical study of the stress field present on orthotropic plates with a circular hole, the relationships between the relaxed strains measured by a rectangular strain gauge rosette and the Cartesian components of the unknown residual stresses are obtained. The theoretical formulas of each influence coefficient allow the user an easy application of the method to the analysis of uniform-residual stresses on a generic homogeneous orthotropic material. Furthermore, to extend the method to the analysis of the residual stresses on orthotropic laminates, caused by initial in-plane loadings, an alternative formulation is implemented. The accuracy of the proposed method has been assessed through 3D numerical simulations and experimental tests carried out on unidirectional, cross-ply and angle-ply laminates.  相似文献   

18.
应用云纹干涉法测量冷挤压孔周残余应力分布   总被引:4,自引:0,他引:4  
本文就冷挤压加工后紧固孔周的残余应力测量问题进行了研究。文中提出了径向切割法以释放欲求剖面的周向残余应力;采用高灵敏度的云纹干涉法测量残余应力释放后引起的附加变形;用载波错位法获得高反差的应变条纹图。  相似文献   

19.
Z-pin复合材料细观模型固化残余应力研究   总被引:1,自引:0,他引:1  
田芳  张俊乾 《力学季刊》2019,40(3):437-446
针对植入Z-pin后碳纤维增强复合材料的微观结构,通过施加Z-pin周期性边界约束条件,建立了Z-pin复合材料单层板单胞细观模型.考虑固化过程中树脂体积收缩、弹性模量随固化度变化和纤维因Z-pin进入偏转因素,运用有限单元法计算了单胞结构在固化成型工艺过程中树脂和纤维应力发展和分布,并研究了Z-pin直径和分布密度对单层板面内残余应力的影响.结果表明:凝胶点之前,树脂模量和残余应力很小,凝胶点之后,树脂模量和残余应力增加较快;残余应力分布与纤维偏转有关;Z-pin直径和分布密度增加会使固化残余应力增大.  相似文献   

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