| 摘要 |
<p>A conveying pipe which extends through a pressurized tank filled with fine grain material, the pipe being subjected to pressure and being adapted to receive the material for conveying from the filling, characterized in that the wall of the conveying pipe is formed with ports through which the material can be introduced into the conveying pipe by thrust, and a pipe member which bears against the inner wall of the conveying pipe and which is axially movable between a position in which it closes the ports and in a position in which the ports are exposed.</p> |
