Vibration problems in long-axis rotating equipment
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The long-axis rotating equipment in our project (submersible pumps, agitators) experiences significant vibration; in some cases, it even shakes. No such problems have been observed in other projects. In the coal chemical project, the material used is coal slurry
Due to various factors such as the high precision requirements for the shafting components of submersible pumps and the stringent installation requirements, careful consideration is needed when selecting them. Especially materials with particles. Your company can look for the causes in aspects such as shaft alignment, three-point (or multi-point) support, and shaft connections. Additionally, your company can choose a self-priming pump provided that the process conditions and site facilities permit it. The mixer is a support issue; there may be a problem with the shaft’s stiffness (due to reasons such as a small shaft diameter or the material used).
It is caused by uneven stress on the impeller and blades; the high solid content of the slurry results in poor fluidity, which leads to excessive negative pressure behind the impeller and blades. The intermittent pulsations in liquid suction by the submersible pump cause unstable flow rates, thereby generating vibrations.
Consider the motor power, the verticality of the pump shaft, as well as the density and viscosity of the material.
Factors such as blade angle, rotation speed, support, and selection are taken into consideration
Flexure exists in the long shafts as well; the stiffness of the shafts is extremely important, and installation accuracy is also decisive
Try changing the blade angle and size
How is shaft alignment measured? These pumps generally arrive as finished products.
If this phenomenon occurs with a new pump, it is due to a quality issue with the pump; if it appears only after the pump has been in operation for some time, it is a problem related to the selection of the pump.
The pump needs to be disassembled, and a centering pin from a lathe is used to hold the center hole of the shaft, in order to measure the runout at the bearing locations and on the shaft journals at the shaft connections. It generally should not be greater than 0.03 MM. Additionally: Currently, the connection at the middle of the long shaft of submersible pumps is a movable connection. The gap value needs to be checked (usually provided by the original manufacturer). Generally speaking, vibration in submersible pumps is difficult to address, due to a combination of factors such as the design by the original manufacturer, manufacturing and installation processes, as well as the skills of on-site engineers and maintenance personnel. I’m not sure if my reply can help you.