| 摘要 |
<p>A valve, including a body, a stem and a backseat characterized in that the backseat is secured in its operational position within the body by a locking means engagable therewith and with the body, a rotational interlock is provided between the locking means and the body and means is provided on the stem, spaced from the backseat, engagable with the locking means for use in rotating the locking means relative to the body and disengaging the locking means from the backseat and body.</p> |
