ZWZDH wedge throttling device is a new type of throttling device developed by our company. Its special structure, non clogging, solid structure and long service life can be used to measure liquid, gas and steam, especially for flow measurement of low flow rate, high viscosity, dust or solid particles and other fluids, such as crude oil, fuel oil, residue, coal tar, wastewater, carbon black solution and other fluids.
2、 Working principle
Wedge throttling device is a differential pressure throttling device that follows the principle of Bernoulli equation in measurement. Wedge orifice plate is a measuring element of a wedge-shaped throttling device, which uses a V-shaped wedge as the throttling element. It leaves the positive and negative pressure tapping holes equidistant before and after the wedge-shaped throttling element. When the fluid flows through the wedge-shaped throttling element, the flow area decreases, the flow rate increases, and the pressure decreases. There is a pressure difference before and after the wedge-shaped throttling element, which is called differential pressure. The square root of the differential pressure is proportional to the flow rate, and the measured differential pressure can determine the flow rate of the fluid.
qv:Volumetric flow rate Δp:differential pressure
elbow flow meter
3、 Technical parameters
1. Nominal diameter: DN25~DN600
2. Accuracy level: 0.5 level, 1 level
3. Range ratio: 10:1
4. Maximum nominal pressure: PN ≤ 16Mpa (up to 42Mpa if there are special requirements)
5. Maximum working temperature: ≤ 450 ℃
6. Pressure tapping interface: flange pressure tapping nozzle for pressure tapping
7. Installation method: flange connection and direct welding
8. Measurable bidirectional flow rate
4、 Performance characteristics
1. Easy to pass through dirty fluids, and dirt is not easy to deposit and adhere.
2. Improved requirements for the sharpness of the orifice inlet and improved measurement accuracy.
3. Suitable for high viscosity media and widely used.
4. Wide range ratio and high accuracy.
5. The pressure loss is smaller than that of the orifice plate, and the wedge-shaped block is an inverted triangle; It has a guiding effect and the fluid transitions smoothly, resulting in a smaller pressure loss than the orifice plate.
6. It has a self-cleaning effect.
7. Wide usage range; The applicable range of Reynolds number is 300~106.
The wedge-shaped throttling device is generally less prone to failure due to its lack of movable parts and sturdy structure. If the measured medium crystallizes and dirt is generated on the surface of the isolation diaphragm of the remote transmission flange or on the light angle of the wedge piece, regular cleaning is required. Cleaning method: After shutdown, the pipeline is purged with steam at an appropriate temperature, or a pressure flange of the transmitter is opened to clean the wedge-shaped parts.