| 摘要 |
<p>The crane is mounted, together with the concrete supply pump, on a vehicle and is intended particularly for concreting road and rail tunnel walls, being arranged to slew on the vehicle. It is also mounted so as to tilt sideways on an intermediate chassis, and derricks under the control of a parallelogram linkage. The end portion of its boom is telescopic, and can be arranged to be maintained constantly in a horizontal position. It can be raised, lowered, and tilted by rams of a hydraulic system. The end portion of the boom can be straight, sliding in the adjacent section which is of square cross section. Each portion can have a pipe section attached to it, the adjacent sections being connected by swivel joints to form a supply pipe for the concrete.</p> |
