I. Product overview

V-cone flowmeter is a new differential pressure flowmeter which appeared in 1980s. It uses V-cone to produce throttling effect in flow field to measure flow. Compared with ordinary throttling, it changes the throttling layout from center throttling to ring throttling. Practice has proved that compared with the general differential pressure flowmeter, the V cone flowmeter has the advantages of high precision, high repeatability, small installation condition limitation, wear resistance, wide measuring range, suitable for dirty media, small pressure loss and so on. As the rectifier of flow field, V-cone becomes a new type of flow sensor with unique performance.

Two, the measurement principle

The V-shaped internal cone throttling device comprises a pointed cone mounted coaxial in the measuring tube and a corresponding pressure inlet. The measuring tube is pre-machined to produce differential pressure at both ends of the pointed cone. The high pressure (positive pressure) of the differential pressure is the static pressure measured at the pressure opening of the pipe wall before the upstream fluid contraction, while the low pressure (negative pressure) is obtained by opening a pressure hole at the central axis of the cone towards the downstream end face. The square root of the difference between high and low pressure is proportional to its volume flow rate. The flow rate can be obtained by measuring the differential pressure of V cone upstream and downstream.

This measurement method is based on the principles of flow continuity equation (law of conservation of mass) and Bernoulli equation (law of conservation of energy). Therefore, its flow calculation formula is the same as other differential pressure flowmeters.

Three, product characteristics

1. The sensor can shape the fluid flow state.

2. Wide range ratio, high precision and good repeatability.

3. Good wear resistance and long-term stability.

4. The required straight pipe section is short and does not require a flow regulator upstream of the flowmeter.

5. The structure of the flowmeter has the function of self-cleaning, does not produce dirty dirt fouling, very suitable for the flow measurement of dirty fluid, such as coke oven gas, wet gas, etc.

6. The inner cone can reduce the amplitude of pulsating oscillation in the measured pressure differential field and thus reduce the noise in the differential pressure signal (as shown in space).

7. No moving parts, good reliability, easy installation.

8. When fluid flows through the inner cone with a special profile, boundary layer is formed around it and the fluid is channeled away from the edge of the tail of the cone to reduce the possibility of it being worn.

9. Low pressure loss, suitable for low static pressure fluid flow measurement occasions.

10. Annular channel, more accurate and effective flow measurement for dirty flow.

Iv. Technical specifications of V-cone flowmeter

1, V-shaped cone flowmeter has direct welding type and flange connection type, square tube type, clamp type, non-standard several structural forms. See the selection table for the scope of product supply.

2, the scope of use: widely used in oil, water, gas, steam all kinds of fluids, especially some high temperature and high pressure, dirty media measurement, obviously stronger than other instruments.

3, accuracy level: ±0.5%

4. Repeatability: 0.1%

5. Working pressure: up to 42MPa

6, working temperature: -40 ~ 700C°

7. Ambient temperature: -40 ~ 80C°

8, range ratio: usually 10:1, choose the appropriate differential pressure transmission up to 60:1

9. Requirements for installing straight pipe section: front 3D straight pipe section, back 1D straight pipe section

10, suitable medium: almost suitable for all gas, liquid medium

11, nominal diameter: DN15 ~ DN2000

12, structural material material: pipeline, surface flange and V cone can provide a variety of materials for users to choose, to meet the needs of different working conditions

13, installation mode: can provide a variety of accessories for users to install, to meet the needs of users in various working conditions, can be installed in any direction, has nothing to do with the state of the medium

14, explosion-proof grade (differential pressure transmitter) : flameproof, intrinsic safety, non-explosion-proof options (differential pressure transmitter)

15, power supply (differential pressure transmitter) : 12 ~ 24VDC

16, output signal (differential pressure transmitter) : 4 ~ 20mA or HART protocol