Orifice Flange Tap Location For Steam Measurement
Orifice Flange Tap Location For Steam Measurement
(OP)
Hello,
I have typically seen installations for orifice plates with the flange taps located on the side of the orifice flanges (in a horizontally run line). Is it acceptable to have the taps located on the top on the flanges? If so, would condensate pots need to be added to the impulse lines? Is there a standard (API, ISA, etc.) which illustrates this type of installation?
The DP transmitter would be located at grade (below the taps).
Best,
KC
I have typically seen installations for orifice plates with the flange taps located on the side of the orifice flanges (in a horizontally run line). Is it acceptable to have the taps located on the top on the flanges? If so, would condensate pots need to be added to the impulse lines? Is there a standard (API, ISA, etc.) which illustrates this type of installation?
The DP transmitter would be located at grade (below the taps).
Best,
KC





RE: Orifice Flange Tap Location For Steam Measurement
A thermal insulation of the orifice and the inflow and outflow length of it is advised.
M777182
RE: Orifice Flange Tap Location For Steam Measurement
RE: Orifice Flange Tap Location For Steam Measurement
Due to maintenance of pneumatic instruments most transmitters were mounted at ground level. With the introduction of electronic d/p cells the maintenance has been reduced so access is not needed as often. Some of the maintenance was caused by the long tubing lengths. The trend I see and follow now is to reduce the length of tubing, mounting the transmitter closer to the orifice taps.
I do want to mention that the past few years I have been running into installations where the taps are off the top of the orifice flange. The tubing goes up then a 90 degree bend into the transmitter. I am guessing at this bend is where the condensate forms to protect the transmitter from getting hot. I figured this was a local engineer doing this and not an industry trend.
I continue to mount the steam flow transmitters below and the taps off the side. The majority of my experience has been in Texas and Lousiana.
Mark
RE: Orifice Flange Tap Location For Steam Measurement
I've seen pigtails used to keep condensate out of the impulse lines, as well.
I believe you should install a bleed/drain valve at a low point to drain any collected condensate once in a while.
RE: Orifice Flange Tap Location For Steam Measurement
RE: Orifice Flange Tap Location For Steam Measurement
RE: Orifice Flange Tap Location For Steam Measurement
I have a similar problem in my factory. The orifice plate where the flange taps are connected is 3 m above the differential pressure installed on the ground level. The orifice plate is installed in a steam superheated line and is used for measure our steam consumption for charges purposes, so I depend on it to save money, I mean: - if my readings are greater than actual consumption, I would pay more than I should. I am not sure, but it seems that the readings are greater than we expect, and I am concerned about the level of condensate of impulse lines. I think they are not at the same level. Do you guys have any proposal to check it? Is there any recommendation on ISO-5167 that could help me to solve this problem? How could I cross check my readings (pitot, ultrassonic, whatelse). I would appretiate a lot ome suggestions from your previous experiences.
Thanks.
LCMS.
RE: Orifice Flange Tap Location For Steam Measurement
Regards,