摘要
半管夹套焊接时不可避免产生残余应力,容易导致其焊接部位开裂泄漏.文中对不同坡口形式的半管夹套进行焊接试验,并利用有限元软件ABAQUS对焊接温度场及残余应力进行数值模拟.结果表明,不开坡口,加热温度不足以使夹套和筒体接触界面的金属完全熔化;开2 mm平行坡口时,焊缝根部温度未达到熔点,焊缝金属流动不足以填充根部间隙,产生未焊透;开45°外坡口,能保证完全焊透,且焊缝成型较好,焊缝根部的残余应力比不开坡口降低33%,筒体残余应力整体降低35%,有利于降低应力腐蚀开裂的敏感性.在实际焊接时,应开坡口焊接,禁止不开坡口或采用2 mm平行坡口.
The residual stresses are generated inevitably during welding of half-pipe jacket,which has a great effect on crack and leakage. In This paper,finite element method and an welding experiment,were used( amerant) the temperature field and the welding residual stress for half-pipe jacket made of 304 stainless steel in three types of groove were calculated. The results show that the temperature at the weld root without groove and 2 mm parallel groove does not reach the melting point,which leads to un-melt in the weld metal and results in defects at weld root. The temperature at the weld root in the 45° outside groove exceeds the melting point,which results in a full penetration and generates a good weld. Compared to that without groove,the residual stresse in weld root and the cylinder with 45° outside groove have been reduced 33% and 35% respectively,which is useful to decrease the risk of stress corrosion cracking. The 45°outside groove should be used in the actual welding process,which can ensure the full penetration and reduce the welding residual stress. The methods of no groove and 2 mm parallel groove are forbidden in the welding of half-pipe jackets.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2017年第1期47-50,共4页
Transactions of The China Welding Institution
关键词
半管夹套
焊接坡口
残余应力
half-pipe jacket
welding groove
residual stress
