| 摘要 |
<p>The internally engaged claws of a grapple are locked in the operate position by a locking plate, below which is a hemispherical deflector dome and there is an external guard ring around the claws. To prevent accidental unlocking of the plate from the claws by the upward gas flow through the channel in which the element is being inserted, a number of supporting feet are fixed to the top of the dome, or to the plate, which maintain a given min. spacing. In addition shims are fitted to the upper mountings of the claws to limit their axial freedom of movement.</p> |
