高压自紧式法兰密封结构研究

Research on High Pressure Self-sealing Flange Structure

对高压自紧式法兰密封结构进行研究,推导自紧式法兰密封比压和螺栓载荷的计算公式,并通过有限元方法进行了验证。结果表明:密封比压与内压呈一阶线性递增的关系:密封面越窄密封比压随内压递增速度越快,法兰端面与T形垫片支撑面间隙越大则初始密封比压越大。对某自紧式法兰进行结构以及热-结构耦合分析,研究内压、温度、弯矩工况的影响。结果表明:升温对高压和低压2种工况的密封性能影响不同,低压下升温使密封比压增大,高压下升温则会使密封比压有所减小;高压自紧式法兰密封受压侧垫片密封面上应力随弯矩增大先减小,但当弯矩增大到一定值后,该应力随着弯矩的增大而增大。

The high pressure self-sealing flange structure was studied,and the calculation formula of its seal pressure and bolt load was derived and verified by the finite element method.It is found that the relationship between the sealing pressure and the internal pressure is in a linear gradient.The narrower the sealing surface,the stronger the self-sealing effect.The larger the gap between the flange end face and the T-gasket support surface,the larger the initial seal pressure.The structural and thermal-structural coupling analysis of a self-sealing flange was also carried out to study the effects of internal pressure,temperature and bending moment.The results show that high temperature has different effects on the sealing performance of self-sealing flange under high pressure and low pressure conditions.The temperature rise will increase the sealing pressure at low pressure,and will reduce the sealing pressure at high pressure.The stress on the sealing surface of the pressure-applied side gasket of the flange is first decreased with the increase of bending moment,but when the bending moment increases to a certain value,the stress is increased with the increase of the bending moment.