HQ-LVD integrated V-cone flow meter is a differential pressure flowmeter developed by our company in the 1980s. Its successful development is a qualitative leap in differential pressure flow measurement. The HQ-LVD conical flow meter is a new type of high-precision differential pressure flow meter. It operates by suspending a specially designed streamlined cone along the centerline of a sealed pipeline for central throttling, calculating flow rate from the differential pressure measured between the upstream pipe wall and the cone's base, hence the name "conical flow meter." Due to its unique structural design, the conical flow meter offers superior performance compared to other differential pressure flow meters.
The HQ-LVD conical flow meter, like the differential pressure flow meter, operates based on Bernoulli's principle of energy conversion in sealed pipelines. Specifically, under stable flow conditions, the fluid velocity is directly proportional to the square root of the differential pressure. When the medium flows toward the cone tip at a certain velocity, the throttling effect of the cone immediately creates a low-pressure zone P2 downstream. The pressure difference △P between the high pressure PI upstream and the low pressure P2 downstream is transmitted through pressure tapping ports to the differential pressure transmitter. Changes in the differential pressure △P can then be used to measure variations in flow rate.

The HQ-LVD conical flow meter consists of an internal conical orifice, a three-valve assembly, heat dissipation components, pressure lead pipes, a differential pressure transmitter, and a flow computer, forming a flow measurement system. For gases and vapors, temperature and pressure compensation can be added to create a mass flow and standard volume measurement system. The LVD conical flow meter is available in two types: flanged (DN15-DN900 or larger) and clamp (DN15-DN150).

High precision and good repeatability: The accuracy of the conical flowmeter is+0.5% of the measured value, and the repeatability is+0.2%.
Wide range ratio and low pressure loss: Under normal circumstances, the range ratio of a conical flowmeter is 10:1. Accurate parameters can achieve a ratio of 30:1, and the pressure loss of the conical flowmeter is only 1/5 to 1/10 of that of the orifice plate, which can greatly reduce operating energy consumption.
Installation requirements for straight pipe section: Due to the unique center streamline throttling structure of the conical flowmeter, the problem of straight pipe section rectification is well solved, directly rectifying irregular fluid into ideal fluid. The front straight pipe section is 0-3D, and the rear straight pipe section is 0-1D.
The unique design of the cone ensures that the fluid flows through it in a gradual process without sudden changes. The flow rate first passes through the cone and then reaches its edge, so the cone is not frequently worn by the fluid.
Good long-term stability: The β value can remain unchanged for a long time, so the instrument does not need to be recalibrated for long-term use.
The working temperature and pressure of a conical flowmeter, like an orifice plate throttling device, depend on the material and grade of the pipeline and flange. Special throttling fluid enables it to measure multiphase water flow, electromagnetic interference media, various mixed gases, etc. Very suitable for measuring dirty media such as Yanqi, coal gas, crude oil, etc.

Widely applicable, capable of measuring high temperature, high pressure, and complex working conditions: The conical flowmeter has a very wide range of operating conditions, with temperatures ranging from -100 ℃ to 500 ℃, maximum pressure of 40MPa, and a wide Reynolds number range of 8X103 to 5X106.
Gases: water, natural gas, air, oxygen, nitrogen, hydrogen, methane, propylene, flue gas, saturated steam, superheated steam, etc.
Liquids: water, oil products, emulsions, pure water, hydrogen peroxide, glycerin, alcohol, purified water, sewage, various corrosive media, etc.
Self cleaning capability: The special design of the differential pressure cone flowmeter ensures that the cone does not have dead zones, so there will be no accumulation of fluid debris, sticky residue, and impurities on the cone, and it has self-cleaning function.

4. Pipeline Type Size:

6. Selection:

HQ-LVD V-cone flow meter Selection Table

7. Precautions for Integrated V-cone Flow Meter:

(1) Users should provide accurate and scientific parameters when selecting, especially when measuring multi-component gases;
(2) V-cone is a differential pressure instrument that also complies with the relevant requirements of differential pressure instrument measurement systems;
(3) The V-cone should be used in the same way as other throttling devices such as orifice plates, and pressure pipelines should be laid according to the requirements of standard throttling devices;
(4) The appropriate model of V-cone should be selected according to the usage situation. When high precision is required, it is best to choose VCH precision measuring tube type
(5) Although the V-cone requires a relatively short straight pipe section, it is better to install it in places with longer straight pipe sections;
(6) When measuring the diameter of small pipes, it is necessary to ensure that there are no large particles or long fibers in the medium, otherwise it will block the flow gap;
(7) V cones for monitoring or general control can be calibrated periodically for about three years depending on the situation;
(8) Precise measurement of V-cones such as trade settlement should be regularly inspected in accordance with relevant national regulations.