Prevention Measures of Centrifugal Pump Vibration and Its Solution

Centrifugal pump vibration control, centrifugal pump vibration solution
① centrifugal pump vibration control from the design control
A. To improve the rigidity of the centrifugal pump, rigidity to control the vibration and improve the pump running invariance is very important. Which is the main point is to properly increase the pump shaft diameter and improve the pump seat rigidity. Increasing the rigidity of the pump requires that the pump be connected to the smallest rotor deflection during a permanent operation, and increasing the rigidity of the pump shaft helps to reduce the rotor deflection and improve the operational invariance. During the operation of the axis of the swing, destruction of sealing, wear ring and many other failures are not related to the rigidity of the shaft. Pump in addition to the strength of the calculation, the stiffness of the calculation can not be missing.
B. Considering the hydraulic design of the impeller The impeller of the pump should be subjected to cavitation and dewatering as little as possible during operation. In order to reduce the pulsating pressure, it is desirable to design the blade in a sloping form.
C. Strict requirements of the impeller static balance data centrifugal pump impeller static balance error value is generally the impeller diameter multiplied by 0.025g / mm, for high-speed impeller (2970r / min above), the static balance error should be reduced by half.
D. Designed with better bearing layout The design of the bearing housing should be better in the form of a bracket. At present, the cantilevered bearing frame is operated, and it seems that the layout is compact and small in size, but the rigidity is insufficient, the vibration resistance is poor and the failure rate is high during operation. The use of bracket-type pump seat can not only improve the rigidity of the support, and can save the pump shell by the manipulation of corrosion-resistant precious metal materials, that is, the pump casing can be thinned wall thickness, to balance their beauty.
E. Robust and reliable board design Some mobile-operated pumps are not very demanding on the root plate because the pump's inlet and outlet pipes are rubber hose and the ISG pipeline pump is in a free condition during operation. And in the process of fixed operation of the pump is often associated with the complex and strong steel pipe in the same way, the pipeline assembly stress, thermal expansion and contraction of the stress and deformation of the ultimate impact on the pump in the fundamental, The design should have sufficient strength and size requirements, for the direct form of the idea of ​​low-speed pump, mechanical weight should be more than 3 times, high-speed pump was more than 5 times.
② centrifugal pump vibration control from the manufacturing quality control
A. Coaxiality should meet the requirements of a lot of vibration or failure of the pump is due to coaxial imbalance caused by coaxial degree of pumping all the rotating parts, such as IS centrifugal pump shaft, bearing, Impeller, pump shell and bearing accuracy, which are required by the design drawings marked with the accuracy of processing to ensure inspection.
B. Smooth manufacturing of impeller and pump shaft pump shaft Overview of the finish to be high, especially the seal and oil seal parts. Pump shaft heat treatment quality should meet the requirements, high speed pump should be more demanding. Impeller of the flow surface should be as smooth as possible, the material distribution should be average, the line should be accurate.
③ centrifugal pump vibration control from the installation of the first way to prevent and control pump vibration
A. The basic plate to find the right horn should choose the output point, the best set in the fundamental and symmetrical placement, the number of horns can not be more than three. Horn placed discomfort At that time, preloading bolts may cause deformation of the root plate.
B. Pump shaft and the motor shaft to ensure coaxial degree of coaxial coaxial axis, should be from the upper and lower and the object of the target off the calibration. Between the two shafts should be left between the required clearance to ensure that the two axes in the course of the operation to do limited axial movement.
C. Pipes should be equipped with a reasonable pump should be to avoid the sudden flow of the pipe and the backlog of air, the entrance is best equipped with a cone-shaped tapered pipe, so that the fluid inhalation gradually shorten the growth rate, so that the fluid into the average impeller.
D. Should be designed to avoid the impact of pipe stress on the pump pipe configuration equipment should be avoided as much as possible when the assembly stress, deformation stress and pipe valve gravity to the pump body, the greater the temperature difference between the pipe system should be set to metal spring Hose to eliminate the influence of pipe thermal stress. E. Check the root bolt is smooth and reliable After the new pump is installed, it is necessary to preload the anchor bolts and then test machine. If this is a matter of neglect, often resulting in the underlying plate under the oblique horn vibration and abdication, and then tightly destroy the level of the fundamental board, which will cause long-term adverse effects on the operation of the pump.
(3) Centrifugal pump vibration solution from the operation and maintenance to solve the pump vibration
① as far as possible the use of low-speed pump Although the high-speed pump can reduce the size of the pump and improve efficiency, but some high-speed pump because of the design and manufacturing problems difficult to comply with the requirements of high-speed operation, poor operation, Therefore, from the operational considerations, in order to reduce the loss of downtime and delay the operating life, or use low-speed pump is more favorable.
② to prevent the operation of small flow or open air pump operation is not allowed to manipulate the import valve to adjust the amount of energy, the operating conditions of the general import valve should be fully open, control the flow can only adjust the export valve, if the operation of the valve long lasting off Pump capacity is too large, running is not economical and affect the life, be careful to change the pump or reduce the speed of running low-speed centrifugal pump.
③ The pump is sealed in a sealed condition. In addition to the leakage caused by running the drip, the most serious problem is that the fluid enters the bearing interior, exacerbates wear, causes vibration and shortens the life. When the packing letter (packing) is applied, in addition to the usual operational requirements, the most easily overlooked problem is to fill the stuffing box. The roundabout groove on the sleeve is often caused by the incorporation of a dirty packing with a sticky soil and sand. If it is to use mechanical seals, the need to pay attention to the problem is moving, static ring material selection summary appropriate, the material can not be offset by the erosion of the working medium, mechanical seal is one of the main factors of multiple failures.
④ strict inspection of the pump running and real-time processing
Check oil temperature and temperature rise of lubricating oil.
B. Check the temperature and leakage of the stuffing part.
C. Check the vibration and abnormal noise. ,
D. To pay attention to the discharge port, suction teeth pressure changes and flow changes, discharge pressure changes violently or decline, often because the suction side of the foreign body is blocked or inhaled the air, to stop the pump in real time.
E. Check the operation of the idea and often pay attention to watch the ammeter pointer fluctuations, the daily inspection of the contents of the contents of the best recorded in the file, found abnormal circumstances should be real-time shutdown, not a delay.