摘要 |
<p>A seismic shut off valve includes a cripple column responsive to seismic movement. A toggle spring overlies the cripple column. Latch pins extend from the toggle spring into a valve body to hold a popper valve in an open position. During an earthquake, the cripple column buckles causing the toggle spring to bow upwardly under spring force exerted on the toggle spring through the latch pins from the popper valve. The latch pins release the poppet valve which shifts to seal against a valve seat in a valve body. A ball joint connecting the valve body and cripple column allow the cripple column to be vertically aligned despite use of the valve on a non-vertical pipe.</p> |