1.1Wear of dredging equipment pipeline:
Wear is closely related to the movement of soil particles, especially the falling speed of soil particles in pipelines. Therefore, it is necessary to study the wear of dredger, pipe and mud pump, analyze the impact of wear on production, and study the methods of controlling wear.
There are three types of pipeline wear:
- Welding wear: the bottom of the weld has large wear.
- Impact wear: it is related to the speed of movement and impact Angle.
- Corner wear: the direction changes and the wear is related to the degree of bending.
Therefore, we should choose steel pipes with high-quality materials to ensure the quality and smoothness of welding seams. The following points should be paid attention to when setting up pipelines:
- When setting up the mud discharge pipeline systematically, it shall strive to be smooth and straight, avoid turning dead corners, minimize the loss of the pipeline along the part and the local damping head, reduce the power load of the ship, and save oil consumption.
- Floating pipe, attached pipe, and self-floating pipe, and other floating structures and pipeline combinations should be reasonably selected according to specific working conditions such as water flow and wind waves, dredger blowing distance and pressure, wear and cost accounting, etc.
- Turn the pipeline in a planned way and rotate 1800 before reaching the ultimate wear thickness. Then rotate 90 for the second time. It can obviously improve service life.
1.2 Factors affecting the wear of centrifugal pump —— dredging equipment
(1) Soil type
The shape of particles is the decisive factor affecting the degree of wear. The velocity of particle movement and the angle of fluctuation and settlement also have some influence on wear. The larger the Angle of particle movement to the tube wall, the more serious the wear. Therefore, the pipe elbow wear is significantly greater than the straight-line wear, large Angle elbow wear is greater than the small Angle elbow.
- Mud transportation
The influence factors of mud transportation are the velocity, pressure, concentration and direction of the mixture, and the velocity is the key factor.
- Pump size and pump material hardness
The influencing factors relate to impeller diameter, impeller width, and pump shell width, and the key factor is the material used.
1.3 Relationship between wear of mud pump and equilibrium
The wear of mud pump can be divided into three types: abrasive wear, impact wear and cavitation erosion. The result of wear is that the lift and pump efficiency are significantly reduced at the same power. Choosing the right time to replace the worn parts of the pump is the key to improve efficiency.
The wear at the nozzle of the dredge pump is related to the equilibrium point of the flow velocity. If it falls at the equilibrium point, the wear will be small. Above or below the equilibrium point will increase the wear.
In addition, do not cut the outer wall of the impeller when cutting the impeller. For wear and tear.
1.4 Methods to control wear of dredging equipment
(1) Choose the right materials of dredging equipment according to the dredging conditions: impeller material, pump shell material, mud pipeline, and rubber cover material and form, etc.
(2) Control the speed of the mud pump so that the working point of the pump is close to the equilibrium point.
(3) Timely repair or replacement of worn parts in a planned way.
(4) Develop a good repair and maintenance schedule, including improvement of existing wear prediction cases and cost development cases, and real-time monitoring and correct analysis of wear process.