| 摘要 |
<p>A top-entry check valve has a valve chamber containing a seat, cage, disc and utilizes a spring retainer to prevent movement of the seat, cage and disc in the downstream direction. A removable bonnet covers an access opening the valve chamber. The seat and cage are a unitary structure for ease in replacing the seat and cage. An annular shoulder in the valve body prevents movement of the seat, cage and disc in the upstream direction. The spring retainer is secured in the valve body by engagement with a lug in the valve body, the unitary seat and cage, the access opening in the valve body and the bonnet. Removal of the bonnet allows access to the valve chamber for replacement of the seat, cage, disc or spring retainer.</p> |
