The Venturi flowmeter is based on a classical Venturi tube, an engineered primary flow element for a most efficient and accurate differential pressure (DP) flow measurement. Thanks to its design, it has an excellent resistance to wear and doesn’t require any maintenance. The service life of the Venturi element is usually equal to the one of the entire plant. It is therefore often the ideal choice in live steam applications of power plants, wet gas flow measurement in natural gas production or CO2 injection, flow measurement of hydrocarbons and LNG as well as in gas-to-liquid processes and refineries. KROHNE offers the complete flowmeter assembly with the Venturi tube, DP transmitter, valves, accessories, engineering, testing and documentation from a single source.
Venturi tubes have one of the lowest permanent pressure loss among all primary elements, contributing to considerable energy conservation and cost savings. KROHNE offers the full range of Venturi tube designs to meet the specific application conditions. Depending on the line size and pressure rating, the Venturi tube will be made of barstock material or sheet metal. Special materials for harsh conditions are available as full material option or often also as cost-effective plasma surface coatings. Special constructions such as redundant tappings, inlet/outlets runs or flow conditioners in accordance with relevant standards (ISO 5167, etc.). can also be supplied.
The throat section and all internal welding are machined to assure perfect surface conditions and flow performance. Welds are outside of the cone-throat transition which makes the construction more precise and rugged compared to standard welded designs.
The sophisticated OPTIBAR DP 7060 and OPTIBAR DP 3050 DP transmitters are the perfect companion for this DP flowmeter solution. They are 3D linearised and ensure advanced performance even at high static pressures. The OPTIBAR DP series has an outstanding long-term stability and a low total cost of ownership with a reduced need for field calibrations.
Specifications
Depending on selected device configuration
General information
Product type | Flowmeter |
Product positioning | For the highest requirements of accuracy and long-term stability |
Measurement principle | Differential pressure |
Nominal diameter / size | DN50…1200 / 2…48 |
Operating conditions
Process pressure |
max. 350 bar / 5077 psi |
Process temperature |
-175°C…+720°C / |
Materials
Measuring tube | Austenitic stainless steel (1.4404/316L), Carbon steel (A105), Alloy steel (ASTM A182 Gr. F12), Alloy steel (ASTM A182 Gr. F22), Alloy steel (ASTM A182 Gr. F91) |
Process connections
Flange connections | EN (1092-1): DN50…1200 ASME (B 16.5): 2…48″ others on request |
Other connections |
Butt weld ends |
Approvals/Standards
Certificates/Approvals Ex | ATEX, IECEx, NEPSI |
Certificates/Approvals Others | NACE, Pressure Equipment Directive (PED), ISO/TR 11583 |
Certificates/Approvals Safety | SIL 2/3 |
NAMUR compliance | NE 107, NE 21, NE 43, NE 53 |
Design standards | ASME MFC-3M, ISO 5167-4 |
Communication
Analogue outputs | 4…20 mA |
Digital outputs | FOUNDATION™ fieldbus, HART®, Profibus-PA, Bluetooth |
Accuracy
Reference uncertainty | 0.15 …0.22 % |