特点 Features：

该类膨胀节的波纹管两端分别与外筒、内筒相连、波纹管波数较多。受外压作用时，它能吸收较大的轴向位移。

The both ends of the bellow for this type of expansion joints are connected to the outer cylinder and the inner cylinder respectively, which has relatively more number of bellow waves. When compressed under external pressures, it can absorb relatively large axial displacement.