Vibration Monitoring - How far do I go?

[gordonl]

We have 2-16MVA turbo generators and 3 turbo blowers similar size. About 10-15 years ago our insurance company requested we install a vibration monitoring system, which has since given up the ghost. We have solicited proposals for new systems using the existing sensors and the proposals are very wide ranging. They include:
- Continuous On-Line monitoring
- Continuous Monitoring with Shutdown logic
- Polling systems (Non-Continuous samplng)
- Stand Alone & Integrated with HMI's

The turbo blowers are process critical so they won't be shut down, and only one ever runs at a time. The generators can be shut down for critical faults, but we would prefer controled shut down.

The cost of these systems vary widely, and we are already doing periodic vibration checks with hand held vibration detectors, (once a month I think) so I'm wondering if an on-line system is required or justified, and if so how far do we go?

Any input would be greatly appreciated.

 

[dgallagher]

In general, there are a variety of low cost continuous monitoring schemes such as loop powered transmitters which could be interfaced to a PLC or Distributed Control System for alarming and or shutdown. Our philosophy is to provide modular, distributive transmitter/monitors and utilize existing plant networks where possible. This will greatly reduce the overall cost of both the monitoring system and installation cost. Take a look at the website

http://www.stiweb.com

for a few ideas and I would be happy to handle your request off-line in detail. You may contact me at 1-800-899-2241.

 

[gordonl]

Going by your member name I'm scheduled to meet with you on this coming Wednesday. Look forward to it.

 

[ScottyUK]

GordonL,

I assume you have looked at the continuous online monitoring & protection schemes from Bently Nevada and CSI (part of Emerson).

European practice on critical drives and generators of this size and capital value would suggest installation of continuous monitoring, if only to allow early diagnosis of a developing fault and allow a planned shutdown rather than the kind of shutdown announced by a shower of sparks and a damaged or wrecked machine.

The plant I work at has Bently Nevada's 3300 series equipment installed on all the turbine-generator trains and on the HP boiler feed pumps. These are all machines with white metal bearings; none of the rolling bearing machines are protected to this extent. The cooling tower fan drives are protected by relatively crude vibration switches, although these are really intended to detect a missing or damaged blade, which happens from time to time.

I think the 3300 series has be superceded by the 3500 series.

 

[dgallagher]

WOW - just looked at the weather forcast for our meeting next week:

Tue Jan 13 Snow Shower -14°/-22° C
Wed Jan 14 Snow Shower -18°/-21° C
Thu Jan 15 Few Snow Showers -15°/-21° C

A little bit cooler than Houston! Look forward to seeing you. Have some hot coffee waiting please.

 

[jbartos]

Suggestion to the original posting: Please, would you elaborate on the insurance "fine print"? Specifically, it would make a big difference if the fine print included the equipment shut-down at a certain equipment vibration level or just mere vibration monitoring and recording for the insurance purposes so that the insurance would be possible to see how the insured equipment is treated with increasing equipment vibration; whether something is being done about the equipment vibration or nothing is being done about the equipment vibration.