- Wide choice of materials
- High volume rates of flow possible
- Orifice plate can be installed in any position
- No power requirement for indication
- Easy to install
- Measuring accuracy +/- 2 % FS
- Scale specific to the process fluid
- Optional:
- Limit value switches
- Bypass extension
| Model Types: | DST-PVC: device in PVC DST-PP: device in PP DST-PVDF: device in PVDF DST-½: device in steel DST-V4A: device in stainless steel DST-…-MSK1: with limit value switch (normally open) DST-…-MSK12: with limit value switch (normally closed) DST-…-MSKW: with limit value switch (change over) |
| DST-PVC: | Ring: PVC Orifice plate: PVC Valves: PVC Bypass Line: PVC Indicator: RA77 / PSU Glass Measuring Tube: Borosilicate glass, optional polysulphone Float: PVC, optional 1.4571, PTFE Gaskets: EPDM, optional FKM Max. Temperature / Pressure (Gauge): 20 °C at 10 bar 40 °C at 6 bar |
| DST-PP: | Ring: PP Orifice plate: PP Valves: PP Bypass Line: PP Indicator: RA77 / PSU Glass Measuring Tube: Borosilicate glass, optional polysulphone Float: PP, optional 1.4571, PTFE Gaskets: EPDM, optional FKM Max. Temperature / Pressure (Gauge): 20 °C at 10 bar 70 °C at 2,5 bar 80 °C at 1,5 bar |
| DST-PVDF: | Ring: PVDF Orifice plate: PVDF Valves: Polysulphone / PVDF can be supplied without valves Bypass Line: PVDF Indicator: RA87 / PSU Glass Measuring Tube: Borosilicate glass, optional polysulphone Float: PVDF, optional 1.4571, PTFE Gaskets: FKM, optional EPDM Max. Temperature / Pressure (Gauge): 20 °C at 10 bar 80 °C at 5 bar 100 °C at 4 bar |
| DST-½: | Ring: S355 (Corrosion protection: epoxy paint, kiln-dried, traffic blue (RAL 5017), satin finished; Corrosion class: C2) Orifice plate: 1.4571 Valves: Brass, Nickel-plated Bypass Line: Steel, zinc plated Indicator: RA65 Glass Measuring Tube: Borosilicate glass Float: Water: 1.4571; Air: anodized aluminium Gaskets: NBR Max. Temperature / Pressure (Gauge): 20 °C at 10 bar Special design: 80 °C at 5 bar |
| DST-V4A: | Ring: 1.4571 Orifice plate: 1.4571 Valves: 1.4571 Bypass Line: 1.4571 Indicator: RA87 Glass Measuring Tube: Borosilicate glass Float: Water: 1.4571; Air: PTFE Gaskets: FKM Max. Temperature / Pressure (Gauge): 20 °C at 10 bar Special design: 80 °C at 5 bar |
DST bypass flow meter operates on the differential-pressure-bypass method. A ring with an orifice plate is installed in the pipeline between flanges. The measuring orifice leads to a constriction and causes a differential pressure. As compensation a volume flow occurs in the bypass which is displayed by a variable area flow meter. This partial flow is proportional to the flow rate in the main pipeline. The unimpeded, straight tube length has to be 6 DN before and 4 DN behind the mounting position. The partial flow can be turned on and off, as required, by installing two ball valves in the bypass line.
PVC model is frequently used in swimming-pool water technology. The models in PP and PVDF is suitable for the flow measurement of aggressive media, e.g. in water
treatment. For other fields of application there is a steel and stainless steel variant (DST ½ and DST V4A).
By installation of electrical limit value switches, which are adjustable throughout the entire measuring range, these devices can be used as detectors.