Electromagnetic flowmeter installation tips

Requirements for installing straight pipe sections

First of all, please note that the sensor itself cannot be used as a load support point. It cannot support the adjacent working pipe. The pipe holding it should be load-bearing. In order to obtain normal measurement accuracy, there must also be a certain length of straight pipe section upstream of the electromagnetic flow sensor, but its length requirement is lower than that of most other flow meters. 90° elbow, T-shaped pipe, concentric reducer, and fully open gate valve must be separated from the sensor inlet flange connection surface by a straight pipe section that is 5 times the diameter (5D) in length. Valves with different openings require 10D; the downstream straight pipe section It is (2~3) D; but it is necessary to prevent the butterfly valve disc from extending into the sensor measuring tube. The lengths of upstream and downstream straight pipe sections proposed by various standards or verification regulations are also inconsistent, as shown in Table 2, and the requirements are higher than usual. This is due to ensuring that the current requirements for level 0.5 instruments are met.

Sensor installation

1) When measuring mixed-phase fluids, choose a place that will not cause phase separation; when measuring two-component liquids, avoid installing them in a place where the mixing is not uniform.

Downstream; when measuring chemical reaction pipes, they should be installed downstream of the section where the reaction is fully completed;

2) Try to avoid negative pressure in the measuring pipe;

3 ) Avoid large motors, large transformers, etc. nearby to avoid causing electromagnetic field interference;

4) Try to avoid high concentrations of corrosive gases in the surrounding environment;

5) Try to avoid Exposed to direct sunlight;

Installation location and flow direction

The axis of the measuring electrode must be approximately horizontal;

The measuring pipe must be filled with liquid;

There must be a straight pipe section of at least 5xD (D is the inner diameter of the flowmeter) in front of the flowmeter, and a straight pipe section of at least 3xD (D is the inner diameter of the flowmeter) behind it; To facilitate installation and disassembly, a pipe expansion joint can be installed after the flow meter.

The flow direction of the fluid is consistent with the arrow direction of the flow meter;

If there is a vacuum in the pipeline, it will damage the lining of the flow meter, so special attention is required;

There should be no strong electromagnetic field near the flow meter; there should be ample space near the flow meter for installation and maintenance;

If the measuring pipe vibrates, there should be fixed supports on both sides of the flow meter;< /p>

When measuring mixed liquids of different media, the distance between the mixing point and the flow meter must be at least 30×D (D is the inner diameter of the flow meter);