1. Requirements for straight pipe sections
Inlet/outlet straight pipe section: inlet should be ≥10×DN; outlet should be ≥5×DN
2. Grounding point requirement
In order to make the instrument work reliably, improve the measurement accuracy, free from external parasitic potential / the sensor should have good grounding, the grounding resistance is less than 10. (If the metal pipe is well grounded, no special grounding device is required) 3.3 Pair installation Location requirements as shown
Insert the electromagnetic flowmeter according to the situation of the pipeline in the field. If the flowmeter without the ball valve is installed, it should be installed on the pipeline without overpressure (that is, the flowmeter without the ball valve can be installed without pressure), and the hole is opened in the pipeline. Diameter 50, ready to weld the connecting welded pipe to the opening of the pipe; for occasions requiring constant flow loading or unloading or no media spillage, a ball valve must be installed, that is, a plug-in electromagnetic flowmeter with a ball valve structure is selected; With a diameter of 50, it is ready to weld the connecting welded pipe to the opening of the pipe.
Measuring range : Recommended range: 0.5m/s to 10m/s continuously adjustable. Maximum use range: continuously adjustable from 0.2m/s to 15m/s
Signal output: 1, the switch quantity can be set to: pulse output (up to 1000HZ); high/low flow alarm; empty pipe alarm; flow direction indication;
Fault alarm; 2, current output: 4-20mA output
Configuration method: 1. Field configuration through three manual keys. 2. Field configuration via remote control. 3. Perform on-site configuration through the handheld communicator.
Memory: The memory that the EEPROM does not disappear, no battery saving.
Third, the spiral vortex flowmeter measurement characteristics
The spiral vortex flowmeter is a flowmeter that began to appear in the 1970s. Its working principle is: the gas that enters the gas swirling vortex flowmeter is first forced by the spiral spinner to accelerate the rotation to form a vortex, the center of the vortex. For the vortex core. The accelerated vortex enters the enlarged section and then decelerates sharply. The pressure rises to produce a recirculation. Under the action of the recirculation, the vortex core makes a spiral precession around the axis of the flowmeter. The flow rate Q can be derived by measuring the vortex precession frequency f by sensing the sensitive component.
Fourth, gas turbine flowmeter and spiral vortex flowmeter measurement difference
The gas turbine flowmeter has a small pressure loss and can be suitable for gas metering in low pressure conveying applications. Gas-injected vortex flowmeters have a slightly higher pressure loss, and gas metering in low-pressure delivery situations sometimes has problems.
Gas turbine flowmeters require high media cleanliness and can be damaged if used improperly. The gas swirling vortex flowmeter gas swirling vortex flowmeter requires no gas turbine flowmeter and is not damaged.
Gas turbine flowmeters are highly accurate. It is the most accurate of all flow meters. The gas spiraling vortex flowmeter is not as accurate as the former.
Selection of measurement types for special industrial and commercial users
2. Case 2: A heavy machine tool factory
The main gas plant of the heavy-duty machine tool factory is 13 production kiln, and there is also a machine repair workshop and 63 mobile burners. The total gas load of all gas facilities is 1837m3/h. See Table 1 for details. The customer promised that all gas facilities could not be fully activated at the same time, the maximum gas consumption required was 1200m3/h, and the minimum pressure required before the furnace was 0.055MPa. The pressure regulator used in the on-site pressure regulating metering box is opened and ready, and the flow meter is in the form of a G1600 turbine table plus bypass.
When debugging the kiln, it was found that the flowmeter in the pressure regulating metering box had a stop-and-go phenomenon. If only some of the kiln was opened or only some of the kiln was used, there would be a phenomenon that the flowmeter did not measure or the measurement error was large.