Selection of sensor installation mode during mass flowmeter installation

Sensors can be installed vertically or horizontally. The installation mode of the sensor should be based on the type of the current being measured and the structure and selection of the sensor itself.

1. Install it vertically

Vertical installation is the installation of sensors on vertical lines, also known as "flag installation". Vertical installation is one of the most recommended installation methods for straight flowmeters and handling and metering applications. Under certain conditions, it can also be used for the installation of bent pipe flow sensor.

1.1 Straight pipe sensor

When the measuring tube of the sensor is straight, the vertical mounting mode can be used regardless of the medium being measured. When measuring liquid slurry, this installation is preferable because it prevents the accumulation of solid particles in the sensor and allows surface gases and oily materials to rise out of the measuring tube. This installation also facilitates cleaning if the process line requires gas or steam cleaning. When using this installation method to measure the liquid medium, the most ideal installation position should be selected in the bottom part of the ascending vertical pipe, so as to obtain static pressure and maintain the stability of zero.

In order to prevent ladder flow (jet flow), a pump should be used to transfer the process liquid bottom-up through the sensor. For the same reason, when the measuring medium is a gas, the medium should be conveyed through the sensor from top to bottom. When the liquid medium needs the flow direction down, if the sensor is directly connected with the unimpeded outlet behind, a throttle hole is installed on the lower cross section of the sensor to prevent the sensor from running empty.

In the loading and unloading metering application, compared with other installation methods, "flag" installation method is also better. In this application, if a check valve is installed downstream of the sensor, it also prevents the liquid from flowing back into the sensor, thus preventing it from being measured twice during loading and unloading. The closer the check valve is to the sensor, the better.

1.2 Bent pipe sensor

When the measuring tube of the pipe penetrator is bent, the situation is relatively complex, which can be roughly divided into two types. First, the measuring tube is "U" type, can refer to the treatment of straight tube type; Second, measuring pipe "Ω" type or triangle type and other curved forms, out of the S-shaped measuring pipe, in the measurement of non-dry gas, liquid containing a small amount of gas and containing solid particles of the grout are not recommended to use the "flag" installation. Because when measuring grout containing solid particles, if the "flag" installation is used, solid particles tend to deposit in the lower part of the perforating measuring tube. When measuring a liquid medium containing a small amount of gas, using the "flag" installation, bubbles may accumulate on the top of the perforator measuring tube. When measuring non-dry gas medium, this installation may cause fluid accumulation in the lower section of the measuring tube.

For the S-shaped pipe penetrator, the "flag" installation is better than the "horizontal" installation under the above medium conditions because of the tubular shape of the measuring pipe.

The disadvantage of "flag" installation is that it is difficult to fix, especially for bent pipe pierers, which is not easy to drive pipeline vibration when the flow is large; Another disadvantage is that the pressure loss and pipeline transport energy consumption is large, in the measurement of the medium with a tendency to precipitate gas must pay attention to ensure the system pressure.