The DK800 glass tube flowmeter is used to measure the volumetric flow of liquids and gases. It is suitable for various applications requiring precise flow measurement, such as supply flow monitoring for meteorological chromatography analyzers and micro-flow monitoring of target samples in other analytical systems. Additionally, it can be connected to different types of pressure regulators to ensure the inlet or outlet pressure of the flowmeter remains stabilized.
Measurement Principle
The glass tube float flowmeter is designed based on the variable area flow measurement principle. It features a vertical conical tube with the larger end facing upward and a specially shaped float that moves freely up and down within the tube.
As the medium flows from the bottom to the top of the conical tube, it causes the float to move upwards. When the three forces acting on the float reach equilibrium, the position of the float remains unchanged.
The three forces acting on the float are Gravity (G), Buoyancy (A), and Fluid thrust on the float (W).
When G=A+WG = A + WG=A+W, the position of the float stabilizes, and the flow rate can be read directly.
Advantages
· Precise measurement can be achieved even at extremely low flow rates
· Suitable for low operating pressures
· On-site indication without auxiliary power supply
· Low straight pipe section requirements
· Easy to replace components
· Debris protection
Features
· No moving parts inside, easy installation and maintenance
· Digital filter amplifier with wider measurement range and better anti-interference performance
· Flow ratio (turndown) up to 33:1
· High accuracy up to ±0.2%
· Max temperature up to +420ºC
· Inline and insertion types
· Integrated and remote mounting options
· Power-off record function
· CE and calibration certification
· Remote mounting type supports pressure and temperature compensation
Technical Parameter
| Application range |
Used for flow measurement of liquid and gas |
| Accuracy grade |
G=2.5%, qG=50%, according to VDI/VDE 3513, Table 2 |
| Operating pressure PS |
PED97/23/EC |
| Test pressure PT |
PED97/23/E |
| Maximum allowable operating pressure PS (TS=100ºC) |
|
| DK…/R |
10 bar |
| DK…/N |
10 bar |
| DK…/PV |
4 bar |
Process Connection
| Standard |
1/4″ NPT female thread |
| Optional |
G1/4, tube, clamp, flange |
| Inlet and outlet straight pipe requirements |
None |
Note: Other connection types can be provided based on requirements.
Material
| Upper and lower valve seat components |
1.4404 / 316L, PVDF, copper nickel plated |
| Selectable materials for upper and lower valve seat components |
HC4 |
| Measuring conical tube |
Borosilicate glass |
| Standard float material |
1.4401/316 |
| Optional float material |
HC4, Ti, POM, glass |
| Valve core |
1.4571/316Ti |
| Valve needle |
1.4404 / 316L |
| Standard gasket |
PTFE/FPM |
| Optional gasket |
PTFE/FFKM, PTFE/EPDM |
| |
EPDM, FFKM |
| Protective cover |
PC (polycarbonate) |
Weight
Standard weight: 0.5 (kg)
Weight with pressure regulator: 2.2 (kg)
Temperature Range
| Operating temperature |
-5 to +100ºC |
| Operating temperature (with switch) |
-5 to +65ºC |
| Ambient temperature |
-20 to +100ºC |
| Ambient temperature (with switch) |
-20 to +65ºC |
Company Profile
Audited Supplier 
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