The cutter suction dredger is one of the most widely used dredger types in dredging projects because of its wide range of soil adaptation and the ability to complete the excavation, transportation, and filling processes in one time. With the application of cutter suction dredger, various methods to increase the efficiency of cutter suction dredger have been found in practice.
- Several controllable factors affecting the construction efficiency of the cutter suction dredger
In the process of construction, the power of generator and mud pump is certain. In the construction process, the possibility of change is very small, and the suitable type of cutter suction dredger can only be selected according to different site construction conditions. In the use of teaching dredger, according to different construction conditions, we can change several aspects to adjust the construction efficiency of the cutter suction dredger.
- Type of cutter head
- Impeller of Dredge Pump
- Speed of Dredge Pump
- Discharge pipeline
- Construction Layout and Method
There are also some methods to improve the construction efficiency of the cutter suction dredger, control the dredging filling distance, choose the pipeline of wear-resistant materials, and so on.
- Construction layout and method
- Layered and subdivided
In order to ensure the high quality completion of the project, under the permissible scope of the excavation capacity of the cutter suction dredger, the layer thickness is continuously optimized through exploration, and the sludge contained in the surface layer can play the role of pipeline transportation “lubrication”, so that the construction efficiency of the upper layer can be maximized. Reasonably determine the width of construction subdivision, maximize the efficiency of ship construction.
- Speed of DredgePump Unit
Under the premise that the length of the discharge pipeline is certain and the size of the shrinkage is determined, although the upper and lower soil were similar, but because of the upper mud lubrication of pipeline, construction flow velocity is higher, in order to avoid the diesel engine overload in the condition of high concentration dredge pump unit, the speed of diesel engine of dredge pump unit under the lower allowable adjustable range is chosen. while the lower hard plastic clay, the transmission pipe resistance increases, the concentration increases, the flow rate begins to decrease, and the diesel engine load also decreases. Therefore, by increasing the running speed of the diesel engine of the dredge pump unit during the construction of the lower layer, the transportation requirements of the hard plastic clay under the lower layer can be met, so as to ensure the stability of pipe blocking and the construction efficiency of the lower layer.
- Rotational speed of cutter
In construction, according to different soil properties, it is very important to reasonably determine the adaptability, cutting force and efficiency of the construction tools to the cutter.
Under the certain power of cutter, different cutter speed has a great influence on the adaptability of different soil. In the safe range of the equipment, appropriately increase the cutter speed, which can reduce the excavation force and easily makes the block soil cut more fragmented; it can also makes the flow pattern of soil pipeline better, and the traverse speed during the construction improves the efficiency. However, the higher the speed of the cutter is not the better, it must be matched with the conveying capacity of the mud pump unit, the high speed of the cutter is easy to make the mud pump effect and cause the increase of the leakage. Reasonably matching the higher rotation speed of the cutter can reduce the size of the soil block and reduce the missing amount of construction soil.
- positive and negative knife construction adopts different inlet quantity
In the actual construction process, because of the soil quality, the amount of cutter positive cutting is less than that of reverse cutting, which can effectively adapt to the requirements of hard plastic clay excavation. Small excavation force exerted by the cutter when cutting downward during positive knife construction, especially in low quality hard construction, it will cause obvious jitter and intermittent halt of ship and bridge, horizontal movement, big fluctuation of reamer pressure, large fluctuation of transverse movement and pressure of the cutter, which will easily cause the cutter blocking and damage the equipment, and the soil is not easy to absorb, the concentration is difficult to improve. When the reverse cutter is constructed, the upward cutting force is greater. The swing winch from the opposite direction to the cutter finish cutting pressure, bridge by bridge winch remain in situ, all of the winch wire rope in tension state. The direction of tension is opposite to the direction of digging, swing winch and cutter together can achieve maximum cutting force. Therefore, although the inlet quantity is obviously larger than the positive knife state, the transverse moving pressure is obviously stable and small compared with the positive knife digging force, the ship bridge is relatively stable and the concentration is easier to increase. It can effectively improve the excavation ability of cutter by reasonably determining the forward movement of positive and negative cutter.