fuyangby@126.com
86 15188770013
fuyangby@126.com
86 15188770013
The intensification of vibration in slurry pumps is the main cause of equipment failure, which may lead to a vicious cycle and affect safe operation. According to statistics, vibration related failures account for 74% of slurry pump failures. The core reasons can be summarized into the following categories:
Identification of core vibration sources
Imbalance of impeller quality: After long-term operation, the impeller wears or forms scars, resulting in uneven distribution of mass. When it rotates at high speed, it generates huge centrifugal force, and the vibration amplitude gradually increases from the motor end to the pump body end, which is the main cause of vibration.
Coupling fit issue: Rigid connections can easily cause resonance, and column pin couplings can experience brief and severe vibrations due to limited axial movement. During installation, it is necessary to ensure that the centers of the two axes coincide and the joint surfaces are parallel, otherwise it will exacerbate vibration.
Fixed system failure: Anchor bolts, bearing bracket bolts, etc. gradually loosen in micro vibrations, resulting in loss of equipment restraint and forming a vicious cycle of "vibration loosening more severe vibration".
Bearing lubrication and wear: Lubricating oil leakage, impurities blocking the oil guide groove or labyrinth seal failure, leading to insufficient bearing lubrication, abnormal vibration caused by direct metal contact, and exacerbating wear.
External factors interference: Unstable feeding can cause cavitation, and unstable foundations or pipeline installation stresses (such as thermal deformation of pipelines caused by high-temperature media) can also transmit vibrations.
Systematic repair plan for vibration faults
For different vibration sources, precise repair measures need to be taken, and the following are hierarchical solutions:
Mechanical structure optimization
Impeller repair and balance correction
Repair welding or replacement of worn impellers must be carried out, and after repair, dynamic balance testing must be carried out to ensure that the unbalance meets the factory standards.
Regularly clean the surface scars of the impeller to avoid imbalanced quality distribution.
Reconnect the coupling
Use a dial gauge to adjust coaxiality, ensuring that the outer circle coincidence deviation is ≤ 0.05mm/m and the end face parallelism deviation is ≤ 0.02mm/m.
The elastic coupling needs to check the aging condition of the rubber ring and replace the failed elastic components in a timely manner.
Maintenance of fastening and lubrication system
Bolt tightening specification: Use a torque wrench to tighten the anchor bolts in diagonal order. It is recommended to tighten them again every 500 hours of operation, and install anti loosening washers in important parts.
Improvement of bearing lubrication
Replace the labyrinth seal with a double end mechanical seal to reduce the intrusion of impurities; Regularly check the cleanliness of lubricating oil and replace it every 3 months.
Establish lubrication record files and dynamically adjust maintenance frequency based on operating temperature (oil change cycle needs to be shortened if it exceeds 65 ℃).
Optimization of operating conditions
Feed system adjustment: Install a filter screen at the pump inlet to intercept large impurities, control the feed liquid level to be above 30% of the minimum cavitation allowance, and avoid the phenomenon of "emptying".
Basic and pipeline renovation: Install shock-absorbing pads on vibration exceeding equipment, set up independent supports for pipelines, add thermal compensation devices to high-temperature pipelines, and eliminate additional stress.
Prevention and monitoring system for vibration faults
Establishing a full lifecycle management mechanism can effectively reduce the occurrence rate of failures, and key measures include:
Preventive maintenance strategy
Standard requirements for periodic inspection items
Daily vibration amplitude monitoring (horizontal/vertical direction) ≤ 4.5mm/s (effective value)
Weekly coupling offset detection radial ≤ 0.1mm, axial ≤ 0.05mm
Monthly lubricant iron spectrum analysis shows that the abrasive particle concentration is less than 20ppm
Annual impeller dynamic balance retest with residual unbalance ≤ G2.5 level
Application of State Monitoring Technology
Vibration spectrum analysis: Monitor the vibration components of 1X (rotation frequency), 2X (misalignment feature), and nX (impeller blade passing frequency) through a portable vibration analyzer to identify fault modes early.
Temperature online monitoring: Install PT100 sensors in the bearing seat to monitor temperature changes in real time, and automatically alarm and shut down when the temperature exceeds 80 ℃.
Through the above diagnosis and repair measures, the downtime caused by slurry pump vibration faults can be reduced by more than 60%, the bearing life can be extended to more than 8000 hours, and the comprehensive maintenance cost can be significantly reduced. It is recommended that enterprises establish a vibration fault case library and continuously optimize maintenance plans based on actual working conditions.
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(Editor in charge: Slurry Pump https://www.fuyangpumps.com/)
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