Dear marine friends, please recommend some materials on vibration diagnosis and analysis!
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Dear marine friends, please recommend some materials on vibration diagnosis and analysis! It’s best for beginners, focuses on practical application, and includes plenty of illustrations! There are rewards!
Summary of Key Points for Vibration Fault Diagnosis
I. Rotor Imbalance
Vibration characteristics of rotor mass eccentricity
1 2 3 4 5 6 7 8
Characteristic frequency, Associated frequencies, Vibration stability, Vibration direction, Phase characteristics, Axis trajectory, Precession direction, Vector area
1× Stable, Radial, Stable, Elliptical, Prograde precession, Unchanged, Unchanged
Changes in vibration due to rotor mass eccentricity as sensitive parameters change
1 2 3 4 5 6
With speed, With load, With oil temperature, With flow rate, With pressure, Other identification methods
Obvious, Not obvious, Unchanged, Unchanged, Unchanged
Vibration tends to zero at low speeds
Causes of rotor mass eccentricity faults
Sources of faults
1 2 3 4
Design, manufacturing, Installation, maintenance, Operation, Machine degradation
Main causes: Unreasonable structure, large manufacturing errors, uneven material quality, low dynamic balance level
Misalignment of components on the rotor, Scaling on the rotor, Loose fit between rotor components
Vibration characteristics of defective rotor components
1 2 3 4 5 6 7 8
Characteristic frequency, Associated frequencies, Vibration stability, Vibration direction, Phase characteristics, Axis trajectory, Precession direction, Vector area
1× Stabilizes after an increase, Radial, Stabilizes after a sudden change, Elliptical, Prograde precession, Stabilizes after a sudden change
Changes in vibration due to defective rotor components as sensitive parameters change
1 2 3 4 5 6
With speed, With load, With oil temperature, With flow rate, With pressure, Other identification methods
Obvious, Not obvious, Unchanged, Unchanged, Unchanged
Sudden increase in amplitude
Causes of defective rotor components faults
Sources of faults
1 2 3 4
Design, manufacturing, Installation, maintenance, Operation, Machine degradation
Main causes: Unreasonable structure, large manufacturing errors, uneven material quality, Large preload on the rotor
1. Operating at excessive speed or under excessive load; 2. Local damage or detachment of components; Corrosion and fatigue of the rotor, stress concentration
II. Rotor Bending
Vibration characteristics of rotor bowing
1 2 3 4 5 6 7 8
Characteristic frequency, Associated frequencies, Vibration stability, Vibration direction, Phase characteristics, Axis trajectory, Precession direction, Vector area
1× 2× Stable, Radial, axial, Stable, Elliptical, Prograde precession, The vector starting point is large and increases as operation continues
Changes in vibration due to rotor bowing as sensitive parameters change
1 2 3 4 5 6
With speed, With load, With oil temperature, With flow rate, With pressure, Other identification methods
Obvious, Not obvious, Unchanged, Unchanged, Unchanged
1) The vibration amplitude is high already at low speeds when accelerating； 2) The phase difference at both ends of the rigid rotor is 180 degrees ； Causes of rotor arc-shaped bending Fault sources 1 2 3 4 Design, manufacturing Installation, maintenance Operation, handling Machine degradation Main causes Unreasonable structure, large manufacturing errors, uneven material quality 1. Improper storage of the rotor, resulting in permanent deformation 2. Misaligned bearing installation, high preload High-speed, high-temperature machines; failure to rotate the rotor promptly after shutdown Poor thermal stability of the rotor, leading to natural bending over time Vibration characteristics of temporary rotor bending 1 2 3 4 5 6 7 8 Characteristic frequency Associated frequencies Vibration stability Direction of vibration Phase characteristics Path of the axis Direction of precession Vector area 1× Stable Radial, axial Stable Elliptical Positive precession Increases during acceleration, decreases after stabilization Changes in vibration due to sensitive parameters 1 2 3 4 5 6 Dependence on speed Dependence on load Dependence on oil temperature Dependence on flow rate Dependence on pressure Other identification methods Obvious Not obvious Unchanged Unchanged Unchanged Large amplitude during acceleration; often fails to start properly Causes of temporary rotor bending Fault sources 1 2 3 4 Design, manufacturing Installation, maintenance Operation, handling Machine degradation Main causes Unreasonable structure, large manufacturing errors, uneven material quality High preload on the rotor Too rapid acceleration, excessive loading Poor stability of the rotor III. Rotor misalignment Vibration characteristics of rotor misalignment 1 2 3 4 5 6 7 8 Characteristic frequency Associated frequencies Vibration stability Direction of vibration Phase characteristics Path of the axis Direction of precession Vector area 2× 1× 3× Stable Radial, axial Relatively stable Double-ring ellipse Positive precession Unchanged Changes in vibration due to sensitive parameters 1 2 3 4 5 6 Dependence on speed Dependence on load Dependence on oil temperature Dependence on flow rate Dependence on pressure Other identification methods Not obvious Obvious Affected Affected Affected 1) Larger axial displacement of the rotor 2) Greater vibration at bearings adjacent to the coupling 3) Vibration increases with increasing load 4) Sensitive to changes in ambient temperature Causes of rotor misalignment Fault sources 1 2 3 4 Design, manufacturing Installation, maintenance Operation, handling Machine degradation Main causes Insufficient thermal expansion, large alignment errors 1. Installation accuracy does not meet technical requirements 2. Insufficient consideration for misalignment under hot conditions 1. Overloading 2. Poor insulation, resulting in different thermal deformations in various parts of the shafting 1. Uneven foundation settlement, poor alignment 2. Large changes in ambient temperature, leading to different thermal deformations of the machine IV. Oil film whirling Vibration characteristics of oil film whirling 1 2 3 4 5 6 7 8 Characteristic frequency Associated frequencies Vibration stability Direction of vibration Phase characteristics Path of the axis Direction of precession Vector area ≤0.5× 1× Relatively stable Radial Stable Elliptical Positive precession Changes in vibration due to sensitive parameters 1 2 3 4 5 6 Dependence on speed Dependence on load Dependence on oil temperature Dependence on flow rate Dependence on pressure Other identification methods Obvious Not obvious Obvious Unchanged Unchanged Whirling frequency varies with the operating angular frequency, with ω≤(1/2)Ω Causes of oil film whirling Fault sources 1 2 3 4 Design, manufacturing Installation, maintenance Operation, handling Machine degradation Main causes Unreasonable design or manufacturing of bearings 1. Improper bearing clearance 2. Insufficient interference fit in the bearing housing 3. Incorrect parameters for the bearing bushes 1. Poor quality lubricant 2. Incorrect oil temperature or pressure Bearing wear, fatigue damage, corrosion, and cavitation V. Oil film oscillation Vibration characteristics of oil film oscillation 1 2 3 4 5 6 7 8 Characteristic frequency Associated frequencies Vibration stability Direction of vibration Phase characteristics Path of the axis Direction of precession Vector area
I. Rotor Imbalance
Vibration characteristics of rotor mass eccentricity
1 2 3 4 5 6 7 8
Characteristic frequency, Associated frequencies, Vibration stability, Vibration direction, Phase characteristics, Axis trajectory, Precession direction, Vector area
1× Stable, Radial, Stable, Elliptical, Prograde precession, Unchanged, Unchanged
Changes in vibration due to rotor mass eccentricity as sensitive parameters change
1 2 3 4 5 6
With speed, With load, With oil temperature, With flow rate, With pressure, Other identification methods
Obvious, Not obvious, Unchanged, Unchanged, Unchanged
Vibration tends to zero at low speeds
Causes of rotor mass eccentricity faults
Sources of faults
1 2 3 4
Design, manufacturing, Installation, maintenance, Operation, Machine degradation
Main causes: Unreasonable structure, large manufacturing errors, uneven material quality, low dynamic balance level
Misalignment of components on the rotor, Scaling on the rotor, Loose fit between rotor components
Vibration characteristics of defective rotor components
1 2 3 4 5 6 7 8
Characteristic frequency, Associated frequencies, Vibration stability, Vibration direction, Phase characteristics, Axis trajectory, Precession direction, Vector area
1× Stabilizes after an increase, Radial, Stabilizes after a sudden change, Elliptical, Prograde precession, Stabilizes after a sudden change
Changes in vibration due to defective rotor components as sensitive parameters change
1 2 3 4 5 6
With speed, With load, With oil temperature, With flow rate, With pressure, Other identification methods
Obvious, Not obvious, Unchanged, Unchanged, Unchanged
Sudden increase in amplitude
Causes of defective rotor components faults
Sources of faults
1 2 3 4
Design, manufacturing, Installation, maintenance, Operation, Machine degradation
Main causes: Unreasonable structure, large manufacturing errors, uneven material quality, Large preload on the rotor
1. Operating at excessive speed or under excessive load; 2. Local damage or detachment of components; Corrosion and fatigue of the rotor, stress concentration
II. Rotor Bending
Vibration characteristics of rotor bowing
1 2 3 4 5 6 7 8
Characteristic frequency, Associated frequencies, Vibration stability, Vibration direction, Phase characteristics, Axis trajectory, Precession direction, Vector area
1× 2× Stable, Radial, axial, Stable, Elliptical, Prograde precession, The vector starting point is large and increases as operation continues
Changes in vibration due to rotor bowing as sensitive parameters change
1 2 3 4 5 6
With speed, With load, With oil temperature, With flow rate, With pressure, Other identification methods
Obvious, Not obvious, Unchanged, Unchanged, Unchanged
1) The vibration amplitude is high already at low speeds when accelerating； 2) The phase difference at both ends of the rigid rotor is 180 degrees ； Causes of rotor arc-shaped bending Fault sources 1 2 3 4 Design, manufacturing Installation, maintenance Operation, handling Machine degradation Main causes Unreasonable structure, large manufacturing errors, uneven material quality 1. Improper storage of the rotor, resulting in permanent deformation 2. Misaligned bearing installation, high preload High-speed, high-temperature machines; failure to rotate the rotor promptly after shutdown Poor thermal stability of the rotor, leading to natural bending over time Vibration characteristics of temporary rotor bending 1 2 3 4 5 6 7 8 Characteristic frequency Associated frequencies Vibration stability Direction of vibration Phase characteristics Path of the axis Direction of precession Vector area 1× Stable Radial, axial Stable Elliptical Positive precession Increases during acceleration, decreases after stabilization Changes in vibration due to sensitive parameters 1 2 3 4 5 6 Dependence on speed Dependence on load Dependence on oil temperature Dependence on flow rate Dependence on pressure Other identification methods Obvious Not obvious Unchanged Unchanged Unchanged Large amplitude during acceleration; often fails to start properly Causes of temporary rotor bending Fault sources 1 2 3 4 Design, manufacturing Installation, maintenance Operation, handling Machine degradation Main causes Unreasonable structure, large manufacturing errors, uneven material quality High preload on the rotor Too rapid acceleration, excessive loading Poor stability of the rotor III. Rotor misalignment Vibration characteristics of rotor misalignment 1 2 3 4 5 6 7 8 Characteristic frequency Associated frequencies Vibration stability Direction of vibration Phase characteristics Path of the axis Direction of precession Vector area 2× 1× 3× Stable Radial, axial Relatively stable Double-ring ellipse Positive precession Unchanged Changes in vibration due to sensitive parameters 1 2 3 4 5 6 Dependence on speed Dependence on load Dependence on oil temperature Dependence on flow rate Dependence on pressure Other identification methods Not obvious Obvious Affected Affected Affected 1) Larger axial displacement of the rotor 2) Greater vibration at bearings adjacent to the coupling 3) Vibration increases with increasing load 4) Sensitive to changes in ambient temperature Causes of rotor misalignment Fault sources 1 2 3 4 Design, manufacturing Installation, maintenance Operation, handling Machine degradation Main causes Insufficient thermal expansion, large alignment errors 1. Installation accuracy does not meet technical requirements 2. Insufficient consideration for misalignment under hot conditions 1. Overloading 2. Poor insulation, resulting in different thermal deformations in various parts of the shafting 1. Uneven foundation settlement, poor alignment 2. Large changes in ambient temperature, leading to different thermal deformations of the machine IV. Oil film whirling Vibration characteristics of oil film whirling 1 2 3 4 5 6 7 8 Characteristic frequency Associated frequencies Vibration stability Direction of vibration Phase characteristics Path of the axis Direction of precession Vector area ≤0.5× 1× Relatively stable Radial Stable Elliptical Positive precession Changes in vibration due to sensitive parameters 1 2 3 4 5 6 Dependence on speed Dependence on load Dependence on oil temperature Dependence on flow rate Dependence on pressure Other identification methods Obvious Not obvious Obvious Unchanged Unchanged Whirling frequency varies with the operating angular frequency, with ω≤(1/2)Ω Causes of oil film whirling Fault sources 1 2 3 4 Design, manufacturing Installation, maintenance Operation, handling Machine degradation Main causes Unreasonable design or manufacturing of bearings 1. Improper bearing clearance 2. Insufficient interference fit in the bearing housing 3. Incorrect parameters for the bearing bushes 1. Poor quality lubricant 2. Incorrect oil temperature or pressure Bearing wear, fatigue damage, corrosion, and cavitation V. Oil film oscillation Vibration characteristics of oil film oscillation 1 2 3 4 5 6 7 8 Characteristic frequency Associated frequencies Vibration stability Direction of vibration Phase characteristics Path of the axis Direction of precession Vector area
Are there any documents? Or more intuitive materials