Tianjin Sure Instrument Science & Technology Co., Ltd. [China]

Detailed Product Description

Vortex flow meters LUGB (Sure 1021) are flow meters that gauge the volume flow of liquids,

gas and steam, volume/mass flow in standard condition based on Karman vortex principle. The meters can also work as flow transducer in the automation system.

Adopting advanced differential techniques along with measurement of isolation, shielding and wave filtering, LUGB vortex flow meters overcome the shortage of low vibration resistance and small signal data disorder that appears in other similar products. Meanwhile, the liabilities of LUGB vortex flow meters are well guaranteed by unique sensor packaging technology and protecting measurement. The products include basic type and compound type. Basic type gauges single flow signal while compound type can gauge temperature, pressure and flow at the same time. Each type includes both entire and separated structure to adjust to varied conditions.

Two. Working principle

Vortex flow meter is made up of a swirl generator, a detected probe and other relevant electronic circuit. Within the flow meter, as the flow moves across the swirl generator, two rows of alternately changed swirl which is called Karman vortex are generated. On the base of Karman vortex principle, Strouhal gave the relational expression between flow rate and vortex frequency:  f = St × V/d 

f : frequency of generating vortex (Hz)

V: average speed of flowing swirl (m/s)

SrStrouhal number (constant)

These alternately changed swirls then generate a series of alternately changed negative pressure and the changed pressure is converted into AC electrical signal through the detected probe. After digital processing, plastic and amplifying process, pulse frequency signal (or standard signal) will be output, which is synchronized and proportional to the swirl.

hree. Traits and use of the flow meter

n         No movable part, stable and steady, easy to install and maintain.

n         Use disturbance elimination circuit and vibration resistance sensor probe, has the ability to resist vibration from environment.

n         Use low power single chip, one 3.2V10AH Lithium battery can lasts over 5 years

n         Amend the nonlinear coefficient of instrument with software in order to improve the measurement accuracy

n         Little pressure loss and wide measuring range

n         Do power-done protection to total flow with EEPROM. The protection time is over 10 years.

Application

This type of instrument can be used to measure the flow in water supply, industry circulation, sewage treatment, oil, chemical reagents, compressed air, saturated or overheated steam, natural gas and other media in various types of large, middle and small pipes.