The conservation of J-integral still exists for pipe welded joint with circumferential through-wall crack.
从工程意义上来说，J积分的守恒性仍然成立。
In this paper, the effects of variables on structure reliability and failure probability of welded pressure pipe with circumferential crack were first calculated by using 3-D elasticplastic stochastic finite element method with 20 nodes isoparametric element. The effects of variables such as external load, crack depth and fracture toughness, which took deferent mean values and variation coefficients, on the reliability and failure probability were researched. The effects of pipe size, circumferential crack angle and strength matching of the welded joint on the reliability of welded pressure pipe were also calculated and discussed. According to the calculating results and analysis, the factor which has greatest effect on the structure reliability was found out.
本文首次采用三维等参单元弹塑性随机有限元方法对含环向内表面裂纹焊接压力管道结构在诸随机变量影响下的结构可靠度及失效概率进行计算，计算研究了外载荷、内表面裂纹深度α和断裂韧性δ〓等随机变量在不同均值处取不同变异系数时对含缺陷焊接压力管道可靠度及失效概率的影响，计算并探讨了管道尺寸变化、内表面裂纹张开角度变化以及管道焊接采用不同强度匹配时在上述诸随机变量的影响下对焊接压力管道结构可靠性的影响，在计算和分析的基础上，找出对管道结构可靠性影响较大的参数。
The simulation shows that: the effect of axial stress and circumferential stress on the strength of the brazed joint is very little, and radial stress is the main factor of joint damage.
模拟结果表明：在焊后冷却过程中产生的轴向应力，周向应力对接头的强度影响较小，径向应力是接头破坏的主要因素。
The results show that, axial stress, circumferential stress and radial stress increase with an increase of tube's axial displacement in the die and the maximums of them all appear at the joint between reducing straight and calibrating straight.
研究发现：在应力分布上，轴向、周向和径向应力随管料在模具中位移增加而增大，三者最大值均出现在减径带与定径带连接处；
The elastic-plastic fracture analyses were carried out for pipes, welded joints and tee-joint tube with circumferential through-wall crack or surface crack. In view of the characteristics which the domestic pipe materials usually have yielding plateau, some numerical computations were conducted to verify the accuracy and reliability of these Jintegral estimation methods. The effects of the mismatching on fracture parameter J-integral for pipe welded joints with through-wall crack or surface crack were discussed in detail. The fracture toughness experiment at the low temperature was successfully conducted for full-scale pipe with circumferential through-wall crack.
采用ADINA和ANSYS非线性有限元数值分析方法，分别对含环向穿透裂纹管道及其接头、表面裂纹管道及其接头进行了弹塑性断裂分析；针对我国压力管道用钢具有屈服平台的特点，验证了J积分估算方法的准确性和可靠性；并对上述两种裂纹形式接头的焊缝非匹配效应对断裂参量J积分的影响进行了深入地研究；首次针对肩部含表面裂纹的焊制三通管道进行了三维弹塑性断裂分析；成功地完成了含环向穿透裂纹全尺寸管道的低温断裂韧度试验。
The circumferential clearance error of the tripod constant velocity joint is one of the main factors which cause these bad influences.
而三球销式等速万向节圆周间隙是产生这些不良影响的主要因素之一。
The changes of the radial deformation and the flange's planeness are induced by the circumferential weld at the joint between the cylindrical shell and the flange;
圆柱形壳体与法兰对接环形焊缝将引起壳体的径向变形及法兰平面度的变化；
Welding deformations due to circumferential welds at the joint between the large cylindrical shell and the flange is studied by model test.
利用模型试验研究了大型圆柱形壳体与法兰对接环形焊缝的焊接变形。
The circumferential square butt joint of small-diameter (≤φ 3mm) stainless steel tubes is difficult to be welded in technique and that is, a smooth joint process of small-diameter tubes. which is widely applied in industry.
细直径（≤φmm）不锈钢管平口环对接接头，是技术难度较大的焊接接头，也是工业应用越来越多的一种细径管平滑连接方法。
The Research on Circumferential Staggered Joint about the Rear Bottom of R_I
一级燃料箱后底环缝错位的研究
Through extending the wear plate at the saddle and using the flexible saddle, the circumferential peak stress at the joint of the shell and the saddle can be decreased efficiently.
本文介绍通过鞍座上垫板的伸出和采用柔性鞍座，即能有效地降低鞍座边角处的环向峰值应力。
A Study on Welding Technique of Circumferential Square Butt Joint of Small-Diameter Stainless Steel Tubes
细直径不锈钢管环缝焊接技术研究