Glass tube rotameter

　　1. Basic parameters

　　1. Use environmental conditions

　　(1) Ambient temperature: -10～50℃;

　　(2) Relative temperature: no more than 95%;

　　(3) There should be no strong corrosive gas around the flowmeter.

　　2. Normal working conditions

　　(1) The flow of the measured fluid is a single-phase, steady flow without pulsation and is full of pipelines;

　　(2) The included angle between the center line of the flowmeter and the plumb line:

　　a, 1.0 and 1.5 level flow meters are not greater than 2°;

　　b. The flowmeter below 1.5 level is not more than 5°;

　　(3) The temperature of the tested fluid is -20～60℃ (normal type) and 0～120℃ (high temperature type). The larger working pressure is shown in Table 1.

　　(4) No mechanical vibration.

　　3. Accuracy level

　　The accuracy grade of the flowmeter is shown in Table 1

　　Table 1

　　Two, installation and use

　　1. Installation

　　(1) Before installing the instrument, carefully inspect whether the glass tube is damaged, take out the filler to prevent the float from jumping, and check whether the float can slide up and down freely.

　　(2) The flowmeter is installed vertically on the pipe (the big end of the cone pipe is upward), and the flow direction is from bottom to top. The piping system where the flowmeter is installed should have sufficient rigidity. When installing, avoid vigorously twisting the flowmeter.

　　(3) To facilitate observation and maintenance, sufficient space should be left during installation.

　　(4) If there is reverse flow in the pipeline, especially when there is water hammer, in order to prevent damage to the flowmeter, a one-way check valve should be installed after the downstream valve of the flowmeter. In order to facilitate inspection, maintenance, replacement of the flow meter and cleaning of the pipeline, it is recommended to install the bypass pipe as shown in Figure 5.

　　(5) When the measured fluid contains relatively large particulate matter or is relatively dirty, a filter should be installed upstream of the flowmeter.

　　(6) When the measured fluid is a pulsating flow, which causes the float to fluctuate and cannot be measured, a buffer or setting device of appropriate size should be installed upstream of the flowmeter to eliminate the pulsation.

　　(7) When used to measure gas, in order to make the meter work stably, the pressure at the outlet of the flow meter should not be too low. The valve upstream of the flowmeter should be fully opened, and the valve downstream of the flowmeter should be used to adjust the flow, and the valve should not be too far from the flowmeter outlet.

　　Attached Table 1: Glass Rotameter Parameter Specification Table

　　2. Use

　　(1) When using the flowmeter, slowly open the upstream valve to fully open, and then slowly open the downstream valve to adjust the flow. When stopping work, slowly close the upstream valve, and then close the downstream valve. If the float does not rise after unscrewing the valve, close the valve to find the cause, and then reopen it after the fault is removed.

　　(2) During use, if the float is found to be stuck, do not use any tools to knock the glass cone tube. It can be eliminated by shaking the pipe or removing the pipe.

　　(3) During use, if the measured fluid is found to overflow at the seal of the glass tube, just remove the front and rear covers and tighten the gland bolts until it does not overflow. If the above method does not work, the sealing packing is generally invalid.

　　(4) If the cone and float are contaminated, they should be cleaned in time.

　　(5) If the working diameter (reading side) of the float is damaged or worn, it should be re-calibrated.

　　(6) When the state of the measured fluid (density, temperature, pressure, viscosity, etc.) is different from the scale state of the flowmeter, the displayed value should be corrected. See Appendix A for the correction formula.

　　Third, the transportation and storage of the instrument

　　In order to prevent the instrument from being damaged during transportation, please try to keep the packing condition of the factory when it is delivered before arriving at the site. During transportation, handle it with care, and it is strictly forbidden to unload it.

　　The storage location of the instrument should meet the following conditions:

　　1. Rainproof and moisture-proof, no corrosive gas and liquid;

　　2. Small mechanical vibration and avoid impact;

　　3. Temperature -10～45℃;

　　4. The relative humidity is not more than 85%.

　　Four, complete instrumentation

　　When the user unpacks, please check the model and code of the instrument according to the packing list, and check whether the instrument is defective, so that you can contact the company in time and solve it in time. Please pay special attention to save the calibration data to facilitate maintenance and use.

　　The complete set of instruments includes:

　　1. 1 glass rotameter

　　2. Spare parts (when the user needs it)

　　3. Random files

　　Product instruction manual 1 copy

　　Product qualification certificate (high-precision instrument including check sheet) 1 copy

　　V. Notes for ordering loans

　　When ordering a loan, please indicate:

　　1. Instrument model, specification (flow range) and code;

　　2. The name, density, viscosity, working temperature, corrosivity, etc. of the tested fluid;

　　3. Use pipeline diameter and working pressure;

　　4. Special requirements must be indicated for special loans (such as the scale according to the working medium, the change of the flow measurement range and the variable material, etc.), which shall be determined after consultation with the company.