Operation Deflection Shape

Introduction

• ODS models is a technique for observing the real behavior of system vibration against any forcing function.
• ODS is the actual machine response, and contains the overall vibration of components of any system, of both the forced and resonant (natural frequency) vibration.
• ODS analysis generates a computer model of a machinery that depicts its motion while running at operating speed & load. You literally “see” how a machine is moving as it operates.
• Model of the system is created, and then its motion is driven by sensor measurements (phase and amplitude) called as relative motion/vibration.
• The relative vibration is measured at various points across the system, that vibration/motion is known as degrees of freedom (DOF). 

Why ODS Analysis?

• When failed to analyze the problem in routine vibration analysis.
• To locate the origin of forcing function in the system.
• When resonance is suspected and source to identify.
• When the vibration transmission path to identify.
• To study the mode shapes of system.
• To identify non linearity in the system.

Resource for ODS Analysis

• Tools

    • 2-Channel vibration analyzer with cross channel measurement option. OR
    • Single channel analyzer with tech option for peak and phase measurement.

• Software

    • ODS analysis software.

• Skills

    • Knowledge of phases analysis.
    • Knowledge of mode shapes and resonance
    • 3D object modeling skill (CAD) for ODS software

ODS Data Collection Procedure

• Make a sketch of machine with dimension in MM or Inch.
• Marks the points on machine according to sketch.
• Mark No. of point on sketch and machine, points depends upon the machine size. (don’t mark too close or too far).
• Consider concrete base, foundation, sole/base plate, motor/pump foot, and associated piping (suction and discharge line) a part of the machine.
• Measure the vibration at different location to point the reference sensor.
• Vibration at reference point should be strong and comparable with other points for good data and stable phase reading.
• Collect the data from all points if possible e.g. Point 1XYZ, Point 2XYZ …..

Immusco provides the services of electric motor testing with state of the art PdM A motor testers. It helps in reducing the overall manufacturing cost of the product as well as enhances the reliability of the plant assets.