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311.
312.
C. Hein S. Hong J. Suh H. Hoffmann N. Kim 《International Journal of Automotive Technology》2008,9(2):211-216
It is essential to develop efficient and cost-effective production methods to achieve or maintain international competitiveness.
An innovative production method, such as rotary blanking, enables manufacturers to both reduce expenses and economize production
time. However, there are not enough numerical analyses for this process. In this paper, numerical simulations of rotary blanking
were performed. After comparing the cutting planes generated by conventional and rotary blanking experimental tests, the cutting
areas of two punch geometries were analyzed. The influence of punch geometry on part quality was then investigated through
simulations. The procedure for die stress analysis was established and stress distributions of the worksheet and the tools
were analyzed. 相似文献
313.
314.
当拱桥跨度较大、拱肋节段较多、地形复杂、建筑高度较高时,可以采取缆索吊装—斜拉扣挂法.先在拼装场地将拱肋分段预制,而后利用缆索吊机将拱段吊装就位,并用扣索将其固定,再吊装后续节段直至合龙的一种方法.该法主要特点是适用性强,特别对于跨越峡谷的大跨度钢管混凝土拱桥.本文就张花高速海螺猛洞河大桥分离式扣挂系统在钢管拱桥中的应用进行简单的分析. 相似文献
315.
压力容器的应力腐蚀及控制 总被引:7,自引:2,他引:7
应力腐蚀是压力容器腐蚀破坏的重要形式,尤其是这种断裂失效呈脆性断裂的特点,易导致灾难性后果。阐述了压力容器应力腐蚀断裂产生的条件和特征,并从合理选材、降低或消除应力和改善环境等方面提出了控制应力腐蚀断裂的技术措施。 相似文献
316.
The three-planar tubular Y-joint (3Y-joint) is the main part of the fatigue assessment of tripod substructures of offshore wind turbines (OWTs). As typical multiplanar tubular joints, 3Y-joints are affected a lot by multiplanar interaction between braces. Moreover, the locations of hot spot stress (HSS) can vary considerably under different load types. Thus, the distributions of stress concentration factor (SCF) and multiplanar interaction factor (MIF) along weld toe curves are necessary to calculate HSS. Considering these requirements, this study focuses on the 3Y-joint considering the wide application of the tripod substructure of OWT. A finite element (FE) analysis method is introduced and validated. Then, a numerical database is established covering common ranges of parameters used in practice. The SCF and MIF of 3Y-joint under in-plane bending moment are analyzed. Distribution formulas are proposed and proved suitable for calculating HSS in engineering design. 相似文献
317.
The stress concentration factors (SCFs) in uniplanar fibre-reinforced polymer (FRP) DKT joints are calculated under five axial loading conditions to determine the maximum SCFs. To this end, 108 finite element models of reinforced DKT joints with different FRPs and geometrical parameters are analysed. Available experimental data and formulas are used to validate the finite element models. The validated finite element models are utilized to investigate the effects of the FRP parameters along with different geometrical parameters on the stress concentration factors in uniplanar DKT joints. The simulations show a reduction of the maximum SCF by around 40% compared to unreinforced DKT joints. The reduction effect increases significantly with increasing the FRP thickness and the number of layers. Despite the notable efficacy of the FRP sheets on the drop of the SCFs in the X-connections, there is not any study or equation on the X-joints with FRP. Therefore, a precise equation is proposed for quantifying the SCFs in X-connections with FRP and is checked against the UK DoE acceptance standard. 相似文献
318.