What standards are followed for the calibration of orifice plate flowmeters?

JJG640-1994 \"Verification Regulations for Differential Pressure Flow Meters\"

So what should be removed for testing and sent over for inspection? Throttle orifice plate? It’s still a differential pressure transmitter

All of them need to be removed for inspection, such as orifice plates, transmitters, and flow integrators.

It should be JJG640-1994 \"Verification Regulations for Differential Pressure Flow Meters\", as orifice flow meters belong to the differential pressure type

Hehe, what standard is there to follow? It doesn’t need to be measured or inspected anyway

This post was last edited by cqdfwy on 2017-5-27 at 10:27. If orifice plate flow meters are used for critical measurements (such as trade measurement or the verification of the readings on trade meters), they should be calibrated in accordance with the standard JG640-1994 \"Inspection Regulations for Differential Pressure Flow Meters\". There are many items that need to be checked – the orifice plates and throttling devices, straight sections of pipe, transmitters, flow accumulators, and related secondary instruments, among others. Additionally, it is necessary to verify whether the measured values fall within the acceptable range； Otherwise, only a routine calibration of the instruments is required (which can also be carried out in accordance with the relevant calibration procedures). This mainly involves calibrating the transmitters, flow accumulators, and related secondary instruments (it is advisable to perform a joint calibration); after that, the orifice plate should be removed for cleaning, inspection, and diameter measurement, to ensure that it can continue to be used.

I’ve never heard of orifice plate flowmeters being used in trade – who would dare to use them? For orifice plates, generally only the factory certification is checked; on-site, the only things that can be inspected are the orifice diameter, thickness, sharpness (visual inspection), and surface finish (visual inspection). The calibration of differential pressure transmitters is something that is done as a standard procedure

This post was last edited by cqdfwy on 2017-6-1 at 10:28. A orifice plate equipped with a high-port valve (a device that allows for the removal and replacement of the orifice plate without interrupting flow) together with a flow computer (specialized measurement and calculation software developed in accordance with relevant technical standards and run on industrial computers) enables comprehensive compensation, thus providing superior flow calculation and measurement management capabilities unmatched by other flow meters. This includes compensation calculations for excessive fluid flow during orifice plate cleaning, adjustments for changes in the dimensional parameters of the orifice plate and pipes due to fluid temperature, accurate calculation of density under various fluid conditions, and compensation for the compression factor of compressible fluids, among others. The common applications of orifice plate flowmeters are relatively simpler, and there are a large number of orifice plate flowmeters used for trade measurement in the natural gas industry – you just may not be aware of it.

You just don’t understand it because you use it too much