Seismic Vibration Probe

1. Consult with your vibration monitoring team and get a survey/assessment done by an independent third party. Check not only the machine parameters but also check process operating parameters/conditions and piping arrangements for anything that may be outside of what was specified for the machine operation.

2. Check the integrity of your installation, find out what type of test equipment is available and what type of simulation can be done with the probe connected to the system with the actual installation i.e. only the probe should be removed from the machine all connections and existing cabling should remain intact. Grounding can have serious adverse effects on machine measurement/monitoring equipment. If all seems to be good then see step 3.

3. Consult with the equipment manufacturer and provide them with your findings, if they agree that the vibration levels are normal or acceptable then it may mean that the trip setpoints etc need to be reviewed and adjusted again in consultation with the equipment manufacturer. Or it may mean that you've got bigger problems (some of which are easily rectified) such as severe pipe strain, misalignment, excessive thermal growth, mechanical imperfections with the machine train itself, civil or structural imperfections with the pump base or plinth etc or other design problems.

No matter what all of the problems can be rectified, it may cost you an arm and a leg but they can be fixed and will save you money and alot of headaches in the long run.

Here are some checks that can be useful,

1. Check your termination of that very probe from the Proximiter and/or extension cable.It might happen that due to some connection fault.

2. If the pump is run for the very first time after a big gap, then it is a big chance that at start , the shaft might experience a GLITCH, that would not be dynamic vibrations, then rather check for electrical/mechanical run-out.

3. If all is well, then call an inspection team with ADRE and see to it that if the vibrations are tolerable you might need to adjust the trip setting, by discussing it with equipment/maint. team and vendor.

So is this an accelerometer? Or a proximity probe?

If it is seismic that leads me to believe that it is an accel.. Your vibration team needs to make sure they are comparing apples with apples. I suggest that they hook their analyzer to the bnc jack on the front, and then use a FMax as far out as possible. The BN monitor uses a peak detector, so very high frequency vibration does not get filtered out like it does on a data collector or other analyzers.

I suspect that the mounted resonance of the accel is being excited, this would be a vibration frequency at 30 Khz or so.

Also you mention it is a pump, if it is a Sundyne pump with an integral gear box, then gear mesh frequency vibration would be very high, and picked up by the 3500 system and might not be picked up by the vibration data collector. Check the frequency span on the accel that is mounted, and compare it with the one the vibration team is using. The BNC accels often go out to 20 Khz, where the standard accels with a data collector are usually only good to 5 Khz.

sound's good thanks I will check and come back to u

One of the reasons for <...HI vibration...> is running one of a number of pumps extensively without running the others; when one of the others runs it can be found that "Brinelling" has taken place in the bearings and that has caused small flats to appear in the shaft and it is the bearing running over these flats that causes vibration.

It's not easily fixed, though it is preventable:

• Don't mount more than one pump on each subframe.
• Toggle the duty on the pumps more frequently, so that there is less risk of flats appearing on the shaft.