Axial Proximity Probe

Insert feeler gauges between the shaft and the sensor, making sure that the gauges remain in contact with the shaft. [?]

This is a instrumentation sensor and work via electrical power and needs to device which could test that sensor , the distance shall be measure by voltage of sensor no feeler gauge.

Friend,

You can use a Bently Nevada TK-3 in order to test the axial probe, Also be necessary use a voltmeter for check the voltage change.

Regards

JP

Thanks your assist

But TK-3 does not applicable for this case , because I need handheld portable device for that , or make a loop for test and set gap and distance in shop after repairing rotary machine or turbine.

Friend,

I agree totally with wrenchpuller, what do you want test?

First, I would recommend you test the complete loop, I mean probe+extention cable+proximitor, and make the calibration curve in order to check if the system has the proper relation mV/mils.

Second, You can use a micrometer in order to see how is working the display(monitor) of the system, I mean how much far or near is the shaft from the probe, If you put 5 mils between the probe and the target for example you will see the same 5 mils in the monitor. This test can be done only after the calibration curve, because with the calibration curve you will know if the system is working good.

After this you will need to know the total axial movement of the shaft, this is done by the mechanics people, and then you will adjust the gap using the vendor recommendation or following the Bently Nevada guides.

I hope this help

JP

Inserting feeler gauges until the sensor detects them would tell how far the shaft would have to move for the sensor to detect it. Why would this not work?

Hi,

Is not clear to me what type of "test" you want to do. If you want to check a probe without using a TK 3 and you are using Bentley Nevada 3300 or 3500 system, here is an option.

Ask the mechanics to set the shaft in the active position and install their dial indicators

set the probe at ten volts or until the indicator on the monitor shows zero

ask the mechanics to move the shaft and compare probe's measurement to the mechanics dial indicator, the reading should be real close.

Thanks

Hi,

Instruments-guy-sav is correct axial probes are very critical, and are generally set in the field and monitor verification is a must, after all the monitor or rack is what's going to activate the trip relay.

With that said; if you insist to set the probe in the shop I have the following suggestion, keep in mind that I am not an expert. I don't know what type of system your probe is going to use, the following explanation is for bently 3500 using 8mm cable.

set the rotor in the active position

connect the probe, extension cable and proximitor together.

supply -24vdc to the proximitor.

connect votlimeter to proximitor's common and signal conexion

adjust the probe to - 10 vdc (look at the voltimeter)

Done....

As I said I am not an expert but I have a good understanding of vibration and thrust systems,I have NEVER set a probe this way, we always set the probes in the field with all the components and a voltimeter.

Thanks