Routine maintenance and maintenance of flowmeter.

1. Vortex street flowmeter is a kind of velocity flowmeter, which can be designed without moving parts. It can measure the medium flow in the pipeline through the probe sensing without contact with the medium, and it is not necessary to maintain and maintain daily. After the table is removed in accordance with the prescribed verification cycle, remove the dirt from the tripod and send it to the legal metering unit for inspection, and pay attention to the light release to avoid falling, touching and smashing.

2. Accurate flowmeter selection, design and installation are of particular importance to the accuracy and life span of the flowmeter, paying special attention to the following points:

(1) flowmeter selection.

Where a mounting site has a large vibration disturbance (close to the source of the vibration, the amplitude is greater than 2g) or the temperature is greater than 350 degrees, the vortex flowmeter should not be selected when the pressure exceeds the vapor measurement of 2.5mpa.

The measurement range of vortex flow meter is 1:10, that is, the maximum flow is 10 times of the minimum flow, and the usual flow rate is the best in 2/3 of the maximum flow.

(2) installation of flowmeter.

A selection of long straight pipe segments (in principle, the longer the better, at least the length of the first 15D, the post-5d length requirement, D as the pipe inner diameter) and avoid the site of the strong vibration to install the flowmeter.

B as far as possible to avoid direct sunlight, had better choose indoor installation, not adding shading devices installed indoors, it is strictly prohibited in the gutter installation (gutter in cooling and ventilation conditions are very poor, moisture can't discharge, flow meter working under high temperature and high humidity environment, life will be greatly reduced)

C. After meeting the requirements of a and b, the flow meter can be installed and cut off a hole in the pipe according to the length dimension of the flow meter. Place the flow meter with the flanges on the open mouth. After fixing the flange on the pipe with the welder, quickly remove the flow meter and weld the flange to the pipe to die. At this point, the valve should be opened to purge the pipe, first the welding slag in the pipe is blown out. When the pipe temperature of welding is reduced to below 400 degree, the flow meter shall be fixed with high strength bolts after the gasket is added, and the screws must be tightened to prevent air leakage. Welding flange is forbidden with flow meter welding, otherwise it may cause damage and permanent damage to the flowmeter. The temperature of the welding point is over a thousand degrees, and the temperature of the detection probe is not more than 400 degrees, and the damage to the wall of the table can be caused by the welding slag, which can affect the measurement accuracy.

D. If the flowmeter is equipped with temperature and pressure compensation, it is recommended that the pressure should be installed at the upstream of the flowmeter 3-5d, and the temperature is installed at 5D downstream of the flow meter. Before installing the flowmeter, install the base of the pressure transmitter, the condensing bend, the cut-off valve and other accessories. When blowing the pipe, the welding slag can be blown out of the pipe. Note that before opening, the pressure transmitter should be filled with water before installing the pressure transmitter to prevent the pressure transmitter from being scalded by high temperature steam, which will affect the accuracy and life span. When the temperature sensor is installed, the welding base is also welded to the pipe, and the temperature sensor is installed after cooling.

E flowmeter and other accessories are fixed to the pipe, and the correct wiring shall be made according to the instructions or wiring diagram (RVVP3 x 0.5)

After the installation and wiring work of f, adjust the size of the valve to see whether the value of the flow meter is changed with the valve opening size. If yes, the wiring is correct and the system is normal! After the installation is completed, the meter and pressure and temperature of the gauge cover are tightened to prevent water intake!