Double-flange zero-setting issue
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For dual-flange transmitters, should the zero point be set when the diaphragm box is removed and hung on the bolt, or after the bolt is tightened?
Hehe~ I can mark it in any way. It seems the original poster is a bit confused; kind people below will help you figure it out. I really don’t have the patience to explain this to you.
The diaphragm box, when hung at the mounting flange, can be marked； A mark can be made when there is no liquid level after the diaphragm box is installed ； If there is a liquid level and a discharge valve, opening the discharge valve can also be indicated.
Which one is more accurate? Is it better to perform calibration after installation?
It’s a method in which the flange is installed on the equipment’s flange; the bolts do not need to be tightened, and pressing ZERO allows the zero point to be set； The second method is calculation: after obtaining the data, perform the corresponding positive and negative offset adjustment on the double-flange transmitter.
Shouldn’t zeroing a double-flange transmitter involve setting both flanges at the same height? Waiting for experts to provide an answer
What you’re referring to is zeroing the header, while I’m talking about zeroing the range
Theoretically, it is assumed that the measurement values of the transmitter remain unchanged before and after the diaphragm box is tightened. However, in practice, due to the fact that the forces acting on the upper and lower diaphragms are not exactly equal (as a result of bolt tightening), the transmitter may show a measurement value after installation (i.e., the liquid level display is not at zero). In such cases, it is possible to perform a zero-point adjustment
Isn’t it better to open the manual valve for calibration after the flanges have been tightened?