By adopting some technology of advanced detection, adding temporary invert, sleeve valve pipe and lock foot bolts, the construction of the tunnel is completed safely and successfully.

暗挖区间隧道通过采用超前探测、增设临时仰拱、袖阀管、锁脚锚管等技术措施，安全、顺利完成了北四环路和北辰桥段的施工。

For ease of installation, insert all flange bolts through the valve flange and then through the sleeve flange, but do not let the bolts extend beyond the surface of the flange rubber (See Figure 4).

为了使安装容易些，可以将所有法兰螺栓穿过阀门法兰，然后穿过套管法兰，但是不要让螺栓超过法兰橡胶表面(参阅图4)。

Other than its excellent abrasion resistance, the Type A Valve can easily be cleaned if the lime solidifies, by actuating the sleeve.

除了优异的抗研磨特性以外，如果石灰固化，A型夹管阀还能够通过驱动套管将固化石灰轻易清除。

The flexing action of the sleeve breaks up any sediment or build-up in the valve, which makes the Type a a reliable low-maintenance valve.

套管的弹性运动可以碎裂淤积在阀门内的任何沉淀物，这使得A型夹管阀成为一款可靠的低维护的阀门。

The flexing action of the sleeve not only unplugs the valve, but also breaks up the lime.

套管的弹性作用不仅不会堵塞阀门，还能够碎裂固化的石灰。