Flow Measurement
Glass Tube Variable Area Flow Meter
GTG20
The Glass Tube Variable Area flow meter GTG20 for liquids and gases feature a tapered glass tube and operate on the float measuring principle. They have a common basic design and various standard connections. The flow-meters are installed in a vertical pipe run with flow from bottom to top.
Glass Measuring Cones
The measuring cones are made of high temperature-resistant stress-free borosilicate glass. Cones and floats are individually replaceable (accuracy class 1.6).
The measuring cones are operated with A III floats. These floats feature three notches on the top guiding edge which cause the floats to rotate and maintain a stable position during flow.
- Large window allows visual control of the process fluid.
- Millimetre scale on the glass cone. The scale is calculated to the calculation method in conformity with VDE / VDI 3513.
MGT30 Glass Tube Variable Area Flow Meter is designed for flow rate measurements in many of industry including, food industry, water treatment plants and the chemical industry.
Flow Meter
| Measuring ranges (100 % values) | Water 20 °C (68 °F): 0.4 – 10,000 l/h Air 1.013 bar abs., 20 °C (14.7 psia, 68 °F): 0.016 – 310 m3/h | |
| Turn-down ratio | 10:01 | |
| Accuracy class | 1 (to VDI/VDE Code 3513, Sh. 2) | |
| Scale | Millimetre scale division or flow units on cone | |
| Float | A III (A III guided on request) | |
Connections
| GTG20 | Screw connection G 1 /2” to G 2” | |
| GTR20 | Tubing nozzle dia. 15 mm to 52 mm ( 1 /2” to 2” ) | |
| GTF20 – Flanges (metric) | DN 15 to DN 50 with holes drilled to DIN 2501 / PN 40 | |
| GTF20 – Flanges (imperial) | 1 /2” to 2” with holes drilled to ANSI B 16.5, Class 150 lbs / RF or 300 lbs / RF (Other versions on request) | |
| GTS20 | Sanitary connection DN15 to DN50 | |
| Max. allowable operating pressure at 20 °C (68 °F) | DN 15, DN 25 / 10 bar ( 1 /2”, 1” / 145 psig) DN 40 / 9 bar (1 1 /2” / 130 psig) DN 50 / 7 bar (2” / 101 psig) (At temperatures > 20 °C pressure drops at the rate of 1% per degree C) | |
| Max. process temperature | – 20 to + 100 °C | |
Overall Height
| GTG20 | 375 mm (14.76’’) | |
| GTR20 | DN 15:400 mm ( 1 /2”:15.75”)> DN 25:450 mm ( >1”:17:72”) | |
| GTF20 | 425 mm (16.73”) | |
| GTS20 | 375mm (14.76”) | |
Materials
| GTG/GTR/GTF20 / SS | Standard: SS304; Optional: SS316 | |
| GTS20 | PVDF | |
| Housing | Standard: SS304; Optional: SS316 | |
| Measuring | Cone borosilicate glass | |
| Float | Standard: SS304; Optional: SS316 | |
| Float stop and insert Gaskets | PVDF | |
| Standard Gaskets | Viton; Optional: BunaN | |
