Orifice plate sens 1

[gasnaturel]

Hi,

I would like to know how we can confirm that the orifice plate is properly and correctly installed in the line of the process (flow sens), just from outside?

thank you

 

[RVAmeche]

What type of system/service?

Typically the construction manager will be responsible for ensuring the installation requirements are met during construction, but if you've hired a calibration or startup tech, they will provide insight.

 

[gasnaturel]

RVAmeche (Mechanical), it's a GE machine MS7001 (compressor AN200), lub oil system we are in startup phase after Major Inspection (MI), the machine is running and we have a doubt in pressure values in the header, we want to know if the orifice plate is correctly instaled without stopping the machine.
thank you.

 

[danw2]

What can go wrong? Some of the things I've run into.
The wrong orifice plate can be installed in the wrong location.
The orifice plate installed backwards. (most vendors stamp ID data on the upstream side)
The orifice plate can be off center between the flanges. (rare)
Orifice obstructed by gasket
Orifice obstructed by debris
If orifice flange unions are not used, the tap holes might be undrilled, drilled in the wrong location, or not fully open due to clogging with metal drill chips or debris. Orifice flange union tap holes can fill with debris (scale)

Most common is that problem is a mismatch between what the pressure transmitter should be configured for (scaling and linear/sq root) and/or the receiver (PLC/DCS/RTU) is configured for. Double square rooting will read higher than expected. The wrong scale on either gives consistently low or high readings at any flow rate.