| 摘要 |
A system usable for dredging may include a suction bypass system for automatically maintaining a sufficiently high, liquid flow velocity. Preferably, a flow sensor monitors flow velocity and when the monitor flow decreases to an extent that plugging may occur, a liquid bypass valve is opened and an intak e line valve is closed until the flow velocity increases whereupon the valves are returned to their original positions. An automatic level cut removes a relatively constant layer of material from a contoured bottom. The illustrated automatic level c ut process comprises adjusting the force with which the suction head engages th e bottom, moving the suction head in a direction opposite to the direction of the swing of the boom to keep the suction head pointing straight ahead, and maintaining the suction head to stay substantially level with the bottom eve n though the angle of the boom increases to the surface of the water body. A leveling device comprising a parallelogram linkage may be used to maintain t he suction head substantially level with the bottom. A predetermined amount of load force may be applied by the head against the bottom. Herein, a winch and cab le and the controller are operated to lift some of the head weight until the desired predetermined head force is applied to the bottom. A walking system moves th e pipe intake for taking a sideways cut without the use of a spud pole, anchor s and anchor lines. Large blade members or feet travels in an endless path with th e feet entering the bottom while vertically disposed and remained disposed vertical ly while entering and leaving the bottom so as not to dig or stir the bottom th at will cause large liquid turbidity. A low turbidity head cleaning system prevents the head from being plugged and debris or sticky material. Preferably, a rotatab le cone-shaped head is provided with spaced rings and bars that define sized openings that limit the size of debris entering into the intake. A fixed com b removes material stuck on the rotating head. A shroud has an open bottom sid e thereby preventing bottom material from escaping and increasing with turbidity. A suction head articulation system keeps the head pointed in the forward direction of dredge advancement to create a smooth finish grade.
|
