Orifice plate differential pressure value
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I currently have an orifice plate flowmeter installed on a DN100 pipeline. It’s used to measure steam; the boiler has a rated steam output of 10 t/h. Previously, due to a malfunction of the differential pressure transmitter, it was impossible to read the differential pressure values. I would like to ask all the experts: if I now replace the differential pressure transmitter with a new one, what should I set the differential pressure value to so that the steam flow rate is displayed correctly? How to calculate the differential pressure in its entirety?
Has the failure reached the point where no communication is possible even with the handheld controller? No instrument specification sheet or orifice plate calculation sheet either?
If the original data is not available, it will be difficult to get things right; if there are calculation sheets, the range can be set based on the parameters in those sheets. If no such sheets exist, one has to purchase new orifice plates according to the process requirements, and then adjust the differential pressure range based on the calculation sheets.
This post was last edited by myface on 2022-1-7 at 14:59. The first step is to find the original calculation documents for the orifice plate; if those cannot be located, the manufacturer can be contacted for assistance. If that also doesn’t work, check the range settings transmitted to the DCS side and try to adjust them accordingly based on the operating conditions. It’s also important to determine whether the squaring is done on the gauge side or on the DCS side, but this approach isn’t very reliable – it’s better to look for relevant documentation. You see, once this transmitter breaks down, it’s no longer possible to retrieve the original setting parameters; instrument management is really chaotic:L
If there are the original transmitter calibration records, then the problem is solved.
6, 10, 16, 25, 40, 50, 1000 kPa. ;P Try a few more times.
First, check the design manual of the original orifice plate flow meter; if it cannot be found, examine the orifice plate itself, as the differential pressure value is usually indicated on it.
I also just took on the role of instrumentation supervisor at this company; there was a half-year gap in my previous employment. Without management dashboard: (
Estimate the steam generation based on the water supply volume, and calculate the range using the current differential pressure
First, if there are design documents, simply follow them to make the settings. If not, it will be a bit troublesome. First, let’s check what the configuration range of the DCS is. Then check where the square root calculation is performed, whether on-site or in the DCS. Then select a measurement value to calculate the K value inversely. Calculating the set differential pressure value based on the range
For balanced flow meters, the transmitter is usually provided by the manufacturer; it should also be listed in the factory-specified range table