Rotary sewage flowmeter

1、 Overview of Rotary Sewage Flow Meter

The rotary sewage flowmeter series metal tube rotary flowmeter has both local display type and intelligent remote transmission type, with pointer display, instantaneous flow rate, cumulative flow rate, LCD display, upper and lower limit alarm output, cumulative pulse output, standard two-wire 4-20mA current output and other forms, providing users with a very wide selection space. In addition, the instrument adopts a high-quality MCU microprocessor system, ensuring the excellent performance of the flowmeter in various application scenarios.
For many years, metal tube flowmeters have been widely favored by industries such as petrochemicals, steel, power, metallurgy, and light industry due to their excellent performance and reliability, as well as their good cost-effectiveness.
Product price:

2、 Structural principle of rotor sewage flowmeter

1. Structure

The MAT50 series metal tube float flowmeter mainly consists of three parts
a、 Indicator (intelligent indicator, local indicator)
b、 float
c、 Cone shaped measuring room

2. Working principle

When the measured medium passes through the conical measuring tube from bottom to top, a differential pressure is generated at the upper and lower ends of the float, forming an upward force. When the upward force acting on the float is greater than the weight of the float immersed in the fluid, the float rises, and the annular gap area increases accordingly. The fluid flow velocity at the annular gap immediately decreases, and the differential pressure between the upper and lower ends of the float decreases. The upward force acting on the float also decreases until the upward force is equal to the weight of the float immersed in the fluid, and the float stabilizes at a certain height. The height of the float position corresponds to the flow rate of the measured medium. The float is equipped with magnetic steel, and when the float moves up and down with the medium, the magnetic field changes with the movement of the float.
a、 For the in-situ type, the rotating magnetic steel in the in-situ indicator is coupled with the magnetic steel inside the float, causing rotation and driving the pointer to indicate the current flow rate through the dial.
b、 For intelligent indicators, a solid-state magnetic sensor in the intelligent indicator converts changes in the magnetic field into electrical signals, which are then converted into A/D signals, processed by a microprocessor, D/A output, and displayed on an LCD screen to show the magnitude and cumulative flow rate.

3、 Main characteristics of rotary sewage flowmeter

1. Suitable for small diameters and low flow rates

2. Reliable work, minimal maintenance, and long lifespan

3. Low requirements for downstream straight pipe sections

4. Has a wide flow range of 10:1

5. Local pointer indication is close to linear

6. The intelligent indicator is equipped with an LCD display, which can display instantaneous and cumulative flow rates, as well as output pulses and alarms

7. Equipped with temperature compensation

8. There are various forms such as on-site type, remote transmission type, jacket type, explosion-proof, corrosion-resistant, etc

4、 Main technical parameters of rotary sewage flowmeter
1. Measurement range: Water 2.5-100000l/h (20 ℃)
2. Range ratio: 10:1
3. Accuracy level: 1.0, 1.5, 2.5
4. Work pressure: DN15, DN25, DN50 are PN4.0MPa * * * up to 10.0MPa, DN80, DN100 are PN1.6MPa * * * up to 6.4MPa
5. Medium temperature:- 40℃～300℃
6. Medium viscosity: DN15：η<5mPa·s（F15.1～F15.3）
η<30mPa·s（F15.4～F15.8）
DN25：η<250mPa·s
DN50～DN150：η<300mPa·s
7. Environmental temperature: LCD type:- 40℃～85℃
Pointer type:- 40℃～120℃
8. Connection form: flange (executed according to standard DIN2501 or manufactured according to the flange standard provided by the user)
9. Instrument height: 250mm
10. Cable interface: M20*1.5
11. Power supply: 24VDC two-wire system 4-20mA or 85-265VAC 50/60Hz (remote transmission type)
12. Alarm output: upper or lower limit instantaneous flow alarm relay output (contact capacity * * * large) 5A@250VAC ）Or open collector output (* * * large) 100mA@30VDC Internal impedance of 100 Ω
13. Pulse output: Accumulated pulse output, with a pulse every 10 seconds at small intervals (AC type) or every 50 milliseconds.
14. LCD display: dual row LCD display, displaying instantaneous flow and cumulative flow.
15. Intrinsic safety explosion-proof: Exia II CT4
16. Material of measuring tube: 316 stainless steel (ordinary type) or lined with polytetrafluoroethylene (anti-corrosion type)

5、 Product selection of rotary sewage flowmeter

6、 Installation of rotor sewage flowmeter

1. Before installation, the top rod, filling material, rubber band, etc. used for transportation protection of the rotor sewage flowmeter should be removed to change the position of the float to a certain extent, and the action status of the converter should be checked. If it is found to be abnormal, adjustments should be made.

2. The rotary sewage flowmeter should be installed vertically on a vibration free pipeline, ensuring that the inclination of the measuring pipe is less than 5 °, and a bypass should be installed for easy maintenance and cleaning without affecting production.

3. When installing the rotary sewage flowmeter, a level should be strictly calibrated, and there should be no stress during assembly. The medium flow direction of the vertically installed rotary flowmeter should be from bottom to top, and the medium flow direction of the horizontally installed rotary flowmeter should be consistent with its marked direction. For the convenience of use and disassembly inspection, it is generally required to install a valve group.

4. The remote transmission part of the metal rotor flowmeter relies on magnetic coupling with the rotor. If the medium contains small particles that are easily adsorbed by magnetic substances, the rotor is prone to wear and jamming, causing inaccurate or impossible measurement. The solution is to install a magnetic filter in front of it.

5. Valves should be installed upstream of the flowmeter, and flow regulating valves should be installed downstream at 5-10 times the instrument diameter.

6. There is no strict requirement for the length of the upstream straight pipe section in the table, but some manufacturers require that the position of installing the flowmeter should ensure that there is a straight pipe section of ≥ 5DN at the inlet and a straight pipe section of not ≤ 250mm or (2-5) D length at the outlet. In fact, the necessity is not significant.

7、 Requirements for the use of rotary sewage flowmeter

1. The control valve in the measurement and control system should be installed downstream of the flow meter. When used for gas measurement, it should be ensured that the working pressure is not less than 5 times the pressure loss of the flowmeter to ensure stable operation of the flowmeter.

2. Before installing the rotary sewage flowmeter, the welding slag inside the pipeline should be blown clean; Remove the stop element from the flowmeter during installation; When using after installation, slowly open the control valve to avoid damaging the flowmeter due to impact.

3. If the required flow range for measurement is wide and exceeds 10, two floats of different shapes and weights can be placed in one instrument. When the flow is small, take the light float reading, and when the float reaches the top, take the heavy float reading. The range can be expanded to 50-100.

4. Liquid instruments are usually calibrated with water flow rate, while gas instruments are calibrated with air flow rate, with the calibration value in the engineering standard state. If the fluid density, gas pressure and temperature under the usage conditions are inconsistent with the calibration, necessary conversions should be made.