Mechanical Vibration » Field Balancing

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Field Balance (Trim Balance)

When the rotating equipment have high vibration during commercial operation, there are many kinds of root cause to resolve the high vibration issue. And, in case of large rotating equipment, it is not easy to perform the completed train test with job coupling & driver at manufacturer’s shop. Then, the high vibration by unbalance, which was not occurred during shop test, can be measured during commissioning due to construction & assembly tolerance and actual operation condition. In order to avoid the critical operation under rotor imbalance condition, INERTANCE can perform Field balancing (Trim balance) as per related balancing grade to reduce residual unbalance. In addition to that, INERTANCE has applied single and dual plane method, and also verified the balancing technic without phase measurement. 

Field balancing for vibration control. Coupling unbalance
Coupling Unbalance

Balancing grade

Permissible residual unbalance grade
Balancing grade, API, ISO

INERTANCE has a capability to perform below kinds of balancing work.

  • Field balancing for rotating equipment
  • Conditional monitoring for rotating equipment
  • Root cause analysis (RCA) for vibration trouble
  • Identification for rigid rotor / flexible rotor
  • Operating speed balancing
  • Single plane balancing
  • Dual plane balancing
  • Single plane balancing without phase
  • Dual plane balancing without phase
  • Pump, Compressor, Coupling, Turbine, etc
  • Residual unbalance check
  • Trim balancing
  • Application for trial weight, rotor sensitivity
  • Balancing grade application as per API, ISO 21940
  • Other root cause such as Alignment, Looseness, Resonance, Rubbing, Oil Whip & Whirl, etc.
Vibration measurement for Root causse analysis, Imbalance-Response-Analysis

Imbalance Response Analysis

Below figure shows the example for single/dual balancing work on coupling hubs. Minimum four (4) times running including final run is necessary to complete the balancing with phase measurement.

Example for imbalance plane and weight application, Trim-Balance
Field-Balance, Trim-Balance

In case vibration monitoring with phase measurement is not available at Site, there is a good way to perform the balancing work, even if there is no information regarding phase. Minimum eight (8) running including final run is necessary to complete the balancing without phase measurement.

7 run method for field balancing(trim balance) without phase measurement
Imbalance Response Analysis

INERTANCE has a capability regarding noise and vibration engineering, and our experts are familiar with assessment of Field Balancing.

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