vibration/alignment/balance

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

Any similar equipment running near?

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

This is a new installed machine, the sister machine has another problem, couldn't start for enough time to monitor the same phenomenon occurrence.

Any similar equipment running near?

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

Was the ˝sister machine˝ ON while measuring this one? 

This is a new installed machine, the sister machine has another problem, couldn't start for enough time to monitor the same phenomenon occurrence.

Any similar equipment running near?

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

How about waterfall and SCL during the vibration change?

Could you show the correlation between Vibration and temperature? How about the winding temperature of motor?

Could you share bearing clearance and shaft diameter?

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

The waterfall shows 1x forward, responsible for the vibration fluctuation.

Scl for the motor during the change is almost stable, however the pump scl in the NDE is abnormal and strange for me, but would it related to motor fluctuation? And if not is it normal, what would the cause of?

Attached waterfall, bearing temperature variations with vibration, the winding temperature is not displayed in MMS unfortunately. Also the motor bearing clearance is not provided, only for the pump is available. 

Thanks again for your consideration 

------------------------------
Ahmed Gomaa

Original Message:
Sent: 10-02-2023 02:04
From: Dinh Ngo
Subject: High motor cyclic vibration

How about waterfall and SCL during the vibration change?

Could you show the correlation between Vibration and temperature? How about the winding temperature of motor?

Could you share bearing clearance and shaft diameter?

------------------------------
Dinh Ngo

Original Message:
Sent: 09-30-2023 02:20
From: Ahmed Gomaa
Subject: High motor cyclic vibration

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

------------------------------
Ahmed Gomaa
------------------------------

It is an interesting case. However, I do not think that this is a morton effect in this case by its period fluctuation and bearing temp not high (64oC).

This motor uses circulation lubrication or Oil Ring. Could you share with us:

• Direct orbit (two time: 1. normal and 1. at high vib).
• All vibration trend from pump + motor in 1 plot.
• Could you zoom to see how it fluctuate in detail.
• Have you checked any abnormal issue related to the machine or nearby.
• A spectrum with high resolution.

In my opinion, I think it could be a modulation case which need to see closely side band of 1X in high resolution.

------------------------------
Dinh Ngo

Original Message:
Sent: 10-02-2023 04:38
From: Ahmed Gomaa
Subject: High motor cyclic vibration

The waterfall shows 1x forward, responsible for the vibration fluctuation.

Scl for the motor during the change is almost stable, however the pump scl in the NDE is abnormal and strange for me, but would it related to motor fluctuation? And if not is it normal, what would the cause of?

Attached waterfall, bearing temperature variations with vibration, the winding temperature is not displayed in MMS unfortunately. Also the motor bearing clearance is not provided, only for the pump is available. 

Thanks again for your consideration 

------------------------------
Ahmed Gomaa

Original Message:
Sent: 10-02-2023 02:04
From: Dinh Ngo
Subject: High motor cyclic vibration

How about waterfall and SCL during the vibration change?

Could you show the correlation between Vibration and temperature? How about the winding temperature of motor?

Could you share bearing clearance and shaft diameter?

------------------------------
Dinh Ngo

Original Message:
Sent: 09-30-2023 02:20
From: Ahmed Gomaa
Subject: High motor cyclic vibration

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

------------------------------
Ahmed Gomaa
------------------------------

The motor uses circulation lubrication

Attached direct orbit for the high vs low values during the fluctuating period

The spectrum doesn't show sidebands

the motor trends shows the fluctuation in both ends, more in the NDE, the pump seems very less in the DE and nothing in the NDE (I don't have right now - will collect later on)

Thanks for your interest

------------------------------
Ahmed Gomaa

Original Message:
Sent: 10-02-2023 09:58
From: Dinh Ngo
Subject: High motor cyclic vibration

It is an interesting case. However, I do not think that this is a morton effect in this case by its period fluctuation and bearing temp not high (64oC).

This motor uses circulation lubrication or Oil Ring. Could you share with us:

• Direct orbit (two time: 1. normal and 1. at high vib).
• All vibration trend from pump + motor in 1 plot.
• Could you zoom to see how it fluctuate in detail.
• Have you checked any abnormal issue related to the machine or nearby.
• A spectrum with high resolution.

In my opinion, I think it could be a modulation case which need to see closely side band of 1X in high resolution.

------------------------------
Dinh Ngo

Original Message:
Sent: 10-02-2023 04:38
From: Ahmed Gomaa
Subject: High motor cyclic vibration

The waterfall shows 1x forward, responsible for the vibration fluctuation.

Scl for the motor during the change is almost stable, however the pump scl in the NDE is abnormal and strange for me, but would it related to motor fluctuation? And if not is it normal, what would the cause of?

Attached waterfall, bearing temperature variations with vibration, the winding temperature is not displayed in MMS unfortunately. Also the motor bearing clearance is not provided, only for the pump is available. 

Thanks again for your consideration 

------------------------------
Ahmed Gomaa

Original Message:
Sent: 10-02-2023 02:04
From: Dinh Ngo
Subject: High motor cyclic vibration

How about waterfall and SCL during the vibration change?

Could you show the correlation between Vibration and temperature? How about the winding temperature of motor?

Could you share bearing clearance and shaft diameter?

------------------------------
Dinh Ngo

Original Message:
Sent: 09-30-2023 02:20
From: Ahmed Gomaa
Subject: High motor cyclic vibration

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

------------------------------
Ahmed Gomaa
------------------------------

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

Morton Effect" is very rare case, but seems u have very good observation. it might be the case. 

we need data file to analysis it. 

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

If I were there, I definitely take high-resolution data to verify the existence of sidebands. Typically, online vibration monitoring systems do not use a high number of lines. In this case, I wouldn't be surprised if the step in the spectrum > 1Hz which is a lot to examine sidebands.

Based on the data, the Martin effect and rubbing are at the top of my possible causes.

Morton Effect" is very rare case, but seems u have very good observation. it might be the case. 

we need data file to analysis it. 

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

Thanks all for your valued comments

I agree the resolution may not be sufficient to capture the nearby sidebands, the set resolution is 0.75 Hz step, if this is a beating which is repeated once every 4.5 minutes, so the beat frequency is 0.22 Hz, so I need 12800 lines in a 1000 Hz span, am I correct? 

I can see the filtered orbit dot is moving with time (during the cyclic event), could be indicative of subsynchronous peak just below the 1X? Or could it be higher like the line frequency, I can think also of electrical source (PPF), I have collected high resolution data with the portable analyser CSI 2140 but couldn't capture sidebands.

If not electrical, what could be the potential causes of very close peak to 1X?

How can I confirm if it is a rubbing or not, other symptoms of rubbing like reverse precession, temp, scl change, doesn't exist, values also are not high, I understand that doesn't eliminate rubbing occurrence, but should I look for other symptoms? And what would be the cause of rubbing, as you all well know it is a secondary effect?

I know these are too many questions in my head 😔, a strange case for me with a new machine 

I will try to collect higher resolution from proximity probes, and I have also requested to increase the lube oil temperature a few degrees to check if it has any effect, still waiting for approval to implement. I will update with the outcomes. 

Thanks all for support

If I were there, I definitely take high-resolution data to verify the existence of sidebands. Typically, online vibration monitoring systems do not use a high number of lines. In this case, I wouldn't be surprised if the step in the spectrum > 1Hz which is a lot to examine sidebands.

Based on the data, the Martin effect and rubbing are at the top of my possible causes.

Morton Effect" is very rare case, but seems u have very good observation. it might be the case. 

we need data file to analysis it. 

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance 

Dear gents,

Kindly I need your expert advise in a case in my site.

The case for a 2-pole, 2980 RPM induction motor, sleeve bearings, driving a multi stage horizontal pump  

trend shows intervals of stable readings and times of fluctuating readings (cyclic vibration) on both motor sides, more observable in the NDE. The fluctuation

appeared to occur during the night, however some events were recorded during the day morning.

- Vibration vs temperature trend showing correlation during steady and cyclic periods with

temperature.

- During the fluctuation period, cyclic vibration magnitude varies from below 20 microns to more

than 50 microns pk-pk within 2 minutes.

- The frequency of cyclic event is around 4.5 minutes

- Full spectrum waterfall showing 1X forward component responsible for the direct vibration

variation.

- The polar plot showing repeating loops - while the machine is under steady conditions without variations in load - 

What do you think the cause of this fluctuation? Is it something we can live with? Any additional plots can reveal more clear vision 

is this a typical symptoms of "Morton Effect"?

Thanks in advance