Urgent------Instrument types and corresponding accuracy requirements at the air separation metering station
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Could someone who works with air separation units tell me about the types of instruments used in air separation metering stations and the corresponding accuracy requirements? Q:Q
It’s not detailed enough; specific questions are needed.
Instrument types at the metering station and corresponding accuracy requirements
I’m not sure what you mean by an air separation metering station. Among the air separation units I have come across, there are no special requirements regarding the accuracy of instruments; meeting the standard specifications is sufficient. Attention should be paid to the material used for the instruments related to liquid nitrogen.
Is the following reasonable? If the measuring instruments in the metering station meet the required types for measuring the corresponding media as well as their allowable error ranges, then such metering station should be considered accurate. Oxygen: Orifice type, ±1.5% of the range (+/–1.5%) Nitrogen, instrument air, plant air: Vortex flow meter type, ±1% of the range (+/–1%) Cooling water: ±2% of the range (+/–2%)
Is the following reasonable? If the measuring instruments in the metering station meet the required types for measuring the corresponding media as well as their allowable error ranges, then such metering station should be considered accurate. Oxygen: Orifice type, ±1.5% of the range (+/–1.5%) Nitrogen, instrument air, plant air: Vortex flow meter type, ±1% of the range (+/–1%) Cooling water: ±2% of the range (+/–2%)
The theoretical accuracy (or calibration accuracy) of these types of instruments can be achieved. In actual use, the error is generally greater than this.
What are you carrying? It’s good enough if some meters can measure trends; what’s the point of talking about accuracy in that case?