Hi All

How are you today?
In this discussion, iam looking for second opinion to monitor Raw Mill at Cement Industry.

The Raw Mill system is Planetary Gear which are Motor as driver, couple with Gearbox as speed reducer of Motor.

The data of Raw Mill are :

Motor speed = 985 Rpm (Power = 5500 KW)

Raw Mill speed = 22 Rpm

Iam measuring Motor, Gearbox and Raw Mill with acceleration sensor 1000mV/G. My question are :

Is'nt realible when i used 1000mV/G to catch up failure on Raw Mill? Iam optimistic to measure Motor and Gearbox. But worry on Raw Mill measurement.

What's generally fault on Raw Mill? Does anyone explain it, when we using Vibration data as a part of Condition Monitoring Strategy.

Operator said, Raw Mill noisy with noise higher than normal Raw Mill. Do you've any rought opinion to explain this? Iam worry if planetary gear has problem (i.e. broken teeth / slip).

Thanks for your opinion my colleagues.

You may want to consider more than one only vibration transducer. @1V/g you will hit load @5 g's and may need an attunator or low pass filter.

What are exactly are you referring to as "raw mill"? Is this the hammer mill coming in or a 'ball' type mill further down-stream? What are the bearing types?

Naratama,
1)What parameters are you using to measure this machine with? That is, are you using displacement, velocity, acceleration, and / or enveloped acceleration?
2)What are the F min and F max being used in each, and how many lines of resolution are being used?
3)What are the bearings used in the machine that you are trying to monitor, and what are the gear ratios?
4) How often are measurements taken?
The vibration unit should be able to lead you to the source of the noise and the root cause of the problem since the noise is generated from vibration (like a person's voice is generated from the vibration of the laroniz in the throat)
Could you draw a sketch of the machine showing the major components - bearings, couplings, gears, things like that - and show where and what measurments are being taken? This would help us to understand the machine so we can help you with this problem.

What type of hardware/software do you have for monitoring? Do you have drawings with bearing, gears, shafts etc.?

How noisy is noisy? Can you post a plot?

At 20 RPM, I have had success with a 100 Mv/G transducer. Bearing frequencies are going to be, at the least, 3.xx orders and possibly higher, so the frequencies you will be looking at are not all going to be 20 CPM.

What type of signal are you getting with the 1000 Mv/G transducer?

Are you by any chance using CSI software or what?

Only my opinion, so

Good morning all,

I didnt measure Raw Mill. In this case, i've roughtly input from maintenance personal if that equipment is noisy. I guess above 85dB.

Raw Mill is "ball" type mill with antifriction bearing. On this process, Raw Mill couple with reducer gearbox and motor. Therefore has three (3) object on this measurement : Motor, Gearbox and Raw Mill. Iam not worry for motor and gearbox, beause we've many experiences. Just curious to Raw Mill.

David,
Vibration parameter will be setup after we know what's characteristic fault of Raw Mill. This time, i dont know anything about that fault. Has anyone can explain it?

Surely, when i had measured, it can be define source of noisy (vibration). But iam worry if my data collector cant read "real" timewave form and spectrum. Do you've any tips to avoid this?

Bill,
Until now, i using vibration data collector and predictive maintenance software from AREVA 01dB-Metravib. For desciption, you can browse in www.01db-metravib.com
As your requirement, i attached Raw Mill drawing on right side. I'll show on the left side, with other posting.

Ralph,
I cant posted noisy plot, because we didnt measure it. Like i said, noisy information has came from maintenance personal.

Raw Mill on left side.

Dear all

I browse and looking for 2nd opinion for this case, i found shock pulse meter (SPM) method has good measurement tools to get real data on Raw Mill.

Beside vibration, we can add Oil Analysis and Thermography to make sure Raw Mill condition. As i know, generally Raw Mill has fault in "ball" wear, broken gear, broken shaft "ball".

Do you've any idea to make sure Row Mill condition?