A suction dredge pump is a type of pump specifically designed for use in dredging operations. Dredging is the process of removing sediment, debris, or other materials from the bottom of bodies of water, such as rivers, lakes, or harbors, to create or maintain navigable channels, deepen waterways, or reclaim land.
A suction dredge pump works by creating a vacuum or suction effect to extract material from the underwater environment. It typically consists of a centrifugal pump, which uses rotating impellers to generate centrifugal force and create suction, and a suction pipe or hose that is submerged in the water or sediment. The pump draws in water and sediment through the suction pipe, and the centrifugal force propels the mixture out of the pump through a discharge pipe.
Suction dredge pumps are commonly used in various dredging applications, including mining operations, construction projects, environmental remediation, and maintenance of waterways. They are capable of handling a wide range of materials, from fine sand and silt to larger rocks and debris, depending on their design and specifications.
Taian Ocean Pump specializes in the production and supply of suction dredge pumps. Taian Ocean Pump’s suction dredge pumps are engineered to handle a wide range of materials, including sand, slurry, gravel, and sediments encountered in dredging projects. Key features typically include high efficiency, wear-resistant construction, robust build quality, customization options, and easy maintenance. These pumps are designed for optimal hydraulic efficiency, utilizing advanced designs to minimize energy consumption and achieve higher flow rates. They often incorporate wear-resistant materials and robust construction to withstand abrasion and harsh conditions. Taian Ocean Pump may offer customization options to meet specific project requirements. Their pumps are designed for easy maintenance and servicing, with user-friendly features that simplify upkeep. For detailed and up-to-date information, please contact Taian Ocean Pump team.
Cause Analysis of Dredge Pump Vibration
The abnormal vibration of the suction dredge pump is the main cause of other failures. At the same time, the failure of the equipment will aggravate the vibration of the equipment, resulting in a vicious cycle, which will seriously affect the safe operation of the imaging equipment, and thus bring corresponding maintenance costs, as well as production losses caused by equipment failures.
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Mass Imbalance of Impeller
The centrifugal force generated by the mass imbalance of the impeller always acts on the dredge pump. When the equipment leaves the factory, due to the corresponding inspection and adjustment of various spare parts of the dredge pump, especially the static / dynamic balance detection and drilling / milling alignment of the impeller, the position of the mass imbalance will be processed. At this time, the impeller is in the relatively best mass balance state, so the dredge pump is also in the most stable state at this time, The vibration of the equipment is also slight. However, after a long time of operation, due to the wear of the impeller and the scabs caused by the adhesion of sand slurry, the overall mass balance of the impeller will be broken, and the corresponding “eccentric load” of the impeller will occur. At this time, the centrifugal force on the heavier side of the dredge pump impeller will increase, especially when the suction dredge pump rotates at high speed, the eccentric load impeller will cause serious unbalanced rotating force. At this time, it will be found that the vibration amplitude gradually increases from the motor end to the pump end.
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Vibration Fault Caused by Coupling
The vibration caused by coupling is common in dredge pumps, especially the rigid coupling. The vibration of motor and pump produces resonance phenomenon in the transmission of coupling, which leads to the intensification of vibration. Even the pin coupling, which is common in dredge pumps, will produce violent and transient vibration because the pin / rubber ring and other components cannot meet the axial movement, although the failure of coupling will also cause the vibration of pump. But it is far less than the vibration caused by impeller failure. The coupler will also be leveled in the later stage after fabrication. Coupling leveling and impeller leveling are also to minimize the unbalanced force generated during rotation. However, in addition to its own mass alignment, the balance of the installation and coordination of the two couplings should also be considered.
In addition to the balance of its own mass, the balance of a pair of couplings must also meet the following two conditions:
1) Make the centers of two pairs of wheels coincide, that is, make the outer circles of two pairs of wheels coincide.
2) Make the joint surfaces (end faces) of the two pairs of wheels parallel (the two centerlines are parallel).
In addition to the above two reasons, the suction dredge pump vibration has the following reasons:
Vibration caused by loose fastening bolts
Vibration caused by bearing wear or insufficient lubrication
Equipment failure caused by unstable feeding
Harm of Suction Dredge Pump Vibration
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Affect the Service Life of Each Spare Part of the Dredge Pump
According to relevant statistics, equipment failures caused by dredge pump vibration account for 74% of equipment failures. During the operation of the pump, due to the imbalance, the centrifugal force increases the load of the bearing, and the vibration beyond the allowable range of the dredge pump will cause the lubricating oil film on the surface of the bearing rolling element to be damaged prematurely, and the bearing cannot be effectively lubricated and dissipated, resulting in the accelerated damage of the bearing temperature rise.
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Damage and Leakage of Mechanical Seal
The vibration of the suction dredge pump will cause the sealing end face of the mechanical seal to be unable to stably fit and operate, resulting in slight material loading in the early stage. The vibration of the mechanical seal will also cause sand slurry particles to be mixed in the friction process of the two end faces, resulting in the early damage of the sealing surface.
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Wear and Leakage of Pump Body
In order to improve the working efficiency of centrifugal pump, the clearance between spare parts inside the pump cavity such as impeller, front / rear guard plate, volute and other components is designed to minimize the clearance between components (under the same conditions, the smaller the clearance, the higher the efficiency of the pump). Vibration will lead to the movement of the pump transmission shaft and the beating of the shaft head. This movement will do great harm to the components inside the pump cavity, and will also lead to the impact or wear of the guard plate and the impeller. This situation will lead to the damage of some spare parts, which will make the pump lose its working capacity or reduce the use efficiency, and the joint surface will leak due to the friction force of each spare part inside the pump cavity.
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Equipment Energy Consumption Increases
The vibration of the suction dredge pump will produce additional friction loss and uneven centrifugal force, which will not only reduce the stability of the pump operation, but also reduce the pump operation efficiency, increase the reactive work, and produce higher power consumption.
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Shaft Breakage
The vibration of the pump will cause the impeller to produce unbalanced centrifugal force, which will make the impeller at the end of the shaft always in an unbalanced state, resulting in excessive stress on the shaft. Long term operation will inevitably produce metal fatigue and lead to shaft failure.
Prevention and Treatment of Pump Vibration
The working conditions and working environment of the suction dredge pump are generally bad, so the failure rate of the dredge pump is often relatively high, which requires that the equipment with higher specifications should be selected as far as possible on the premise of meeting the production technical requirements, and at the same time, a good working environment should be ensured during feeding.
The centrifugal pump will produce partial cavitation during operation, especially in the case of insufficient feeding, which will aggravate the vibration of the pump. The vibration caused by short-term cavitation is caused by the uneven distribution of liquid in the pump cavity. By stabilizing the feeding of the centrifugal pump or adjusting the speed of the outlet valve pump, the vibration of the pump can be effectively eliminated.
Lubrication should not only consider the oil level and quantity of lubricating oil, but also consider the viscosity of lubricating oil. When the viscosity of the lubricating oil is insufficient, the centrifugal pump will also produce vibration. When the centrifugal pump is running, the temperature of the bearing box will rise. When the temperature rises, the viscosity of the lubricating oil will decrease. Therefore, when detecting the oil level and quantity of the equipment, it is also necessary to ensure that the temperature of the equipment is within the appropriate range. When the temperature of the equipment rises, the reason should be found out in time, otherwise the bearing will also be vibrated and damaged due to poor lubrication.
In the “slight vibration” state, the bolts will loosen. When reinstalling the equipment after maintenance, you can apply some thread locking agent on the bolts, which can not only prevent the loosening of the bolts, but also prevent the damage of the bolts. When disassembling, you can melt the locking agent only by heating. Although the investment is small, it is essential for the reinstallation of the equipment.
Stable feeding. In addition, sedimentation, scarring and large particle blockage in the slurry at the later stage of use will cause the feeding process to fail to meet the flow requirements of the suction dredge pump, so it is necessary to clean the pipes and valves. Control the flow by adjusting the outlet valve, not by adjusting the inlet valve.
Conclusion
The analysis of the causes and harms of vibration in suction dredge pumps sheds light on the importance of understanding and addressing this issue. Vibration in suction dredge pumps can arise from factors such as imbalance, misalignment, cavitation, wear, or operating conditions. These vibrations can have detrimental effects on the pump’s performance, efficiency, and lifespan.
Identifying the root causes of vibration is crucial in implementing effective solutions. Regular maintenance, inspection, and balancing of components can help mitigate imbalance-related vibrations. Ensuring proper alignment between pump and motor, as well as addressing cavitation issues, can also minimize vibration.
The harms of unchecked vibration in suction dredge pumps can lead to increased wear and damage to impellers, bearings, and other components. It can result in reduced pump efficiency, higher energy consumption, and increased maintenance requirements. Furthermore, excessive vibration can compromise the overall stability and integrity of the dredging system.
By understanding the causes and harms of vibration in suction dredge pumps, operators and maintenance personnel can take proactive measures to prevent and mitigate this issue. Implementing regular inspections, following manufacturer guidelines, and seeking professional assistance when needed can help maintain optimal performance and prolong the service life of suction dredge pumps.
