Rod Drop Probe

[mu85922]

Can anyone enlighten me the necessity of having a Rod Drop Probe which observes the piston rod position in reciprocating compressor? I am slightly confused if we really need this type of probe or not required for our equipment details below:

Compressor is oil lubricated diaphragm type with:
Frame configuration = L type
Diaphragm head stroke = 160 mm
Rated speed = 265 rpm
Piston speed = 1.4 m/s
Max operating rod load = 73.9 KN for 1st stage and 76.7 KN for 2nd stage.


Regards,
Mu85922

 

[sms]

Typically rod drop probes are not applied to diaphragm machines. The primary purpose of the probe is to measure the position of the rod on large recip compressors in an effort to determine if the rider band that supports the piston in the cylinder is wearing out. As your diaphragm compressor does not have rider bands, this is pretty much not required.

The secondary purpose of a rod drop probe is to look at the piston rod runout in an effort to determine if there are alignment problems, packing problems, cross head problems, etc. Since your diaphragm machine is very short stroke, and given the configuration these are not really issues for you either.

Bottom line is that for your machine, you don't need them. If the instrument salesman insists that you do, tell him he needs to go do some homework on the application.

 

[mu85922]

sms thank you very much for your great clarification. One more thing I would like to ask you, is there any good vendor you could recommend that can manufacture this kind of compressor?

 

[sms]

I don't have a lot of experience with diaphragm compressors, but I have had good experience with both Burton Corblin in France and Nuemann and Esser in Germany on other types of compression equipment, and these two companies make diaphragm compressors as well.

I have lots of experience with diaphragm pumps, and for those I like Lewa and Bran-Luebbe. We put a number of these in a plant we recently built in Holland.