Quasi-linear tube Coriolis mass flowmeter

Abstract

The invention provides for a quasi-linear tube Coriolis mass flowmeter (CMF), which is used for direct high-accuracy measure for mass flow and comprises two quasi-linear tube measuring tubes with the same structure in parallel, a vibration exciter, two detectors, four distance plates, two flanges, two end connecting tubes, two shunts and four matching blocks. The quasi-linear tube Coriolis mass flowmeter (CMF) can effectively improve the properties and quality factors of a resonance sensor, greatly reduces volume of a flowmeter, lowers flow field influence, and has small flow resistance, low pressure loss and simple installation and processing; the measuring tube has favorable dynamic equilibrium, can measure the liquid mass flow with high viscosity and high impurity content, further expands the application range of the CMF and satisfies the industrial development requirements on accuracy and range of flow measurement; and the invention plays a greater role in saving raw materials, lowering production cost, reducing environment pollution, improving profit margin and promoting product quality.

Description

technical field [0001] The invention relates to a Coriolis mass flowmeter (CMF), in particular to a straight-tube type Coriolis mass flowmeter, which belongs to the field of testing and measuring instruments and is used for direct and high-precision measurement of mass flow. Background technique [0002] The development of mass flow measurement technology is the focus of the development of national science and technology in the field of process control. In order to achieve high-accuracy and high-reliability measurement of various media under complex environmental conditions, Coriolis Mass Flowmeter (Coriolis Mass Flowmeter, CMF, also known as Coriolis mass flowmeter) has become one of the important development technologies in this field because of its superior performance, and it meets the major needs of the country. CMF can directly measure the mass flow of the fluid in the pipeline with high accuracy, and use the Coriolis effect generated when the fluid flows through the v...

AI Technical Summary

Problems solved by technology

[0006] The straight tube type is opposite to the curved tube type. Due to its high rigidity and high resonance frequency, it is generally 700~1000Hz, and its amplitude is small, about 60μm; due to its high frequency, it is relatively different from the general mechanical vibration frequency in industry. Large, so it is not easy to be disturbed by external vibration; it is not easy to accumulate gas and residue, and the overall size is small; in order to prevent the resonance frequency from being too high, the tube wall is designed to be thinner, about 1 / 4~1 / of the elbow 2, so the wear resistance and corrosion resistance are poor

However, the phase difference is on the order of microseconds, and the processing of electrical signals is difficult, which severely limits the measurement range of CMF, and the sensitivity of this traditional vibrating straight tube CMF is low and affected by temperature fluctuations

The straight tube type or similar straight tube type CMF developed and applied at home and abroad, such as the published patents are: Coriolis mass flowmeter (patent application number is 00129058.4), which is made into a bow that bends in one direction. It is a curved pipe, the flow rate is not stable, and the fluid is easy to generate adsorption and precipitation on the inner wall of the pipe; the installation and processing are complicated, and the dynamic balance characteristics are poor

[0007] At present, there are some restrictive factors in the developed CMF: for example, the overall performance of the CMF measuring tube design is poor, the installation of the pipeline is unstable, and the mechanical realization of the tube shape is difficult; the CMF is sensitive to external vibration interference; the CMF system cannot be used for Measuring low density media

When measuring gas-containing liquids, if the gas content is too large, the measurement accuracy will be affected; the measuring tube is affected by the design, processing and installation process, and its dynamic balance characteristics are poor, which directly affects the performance of the CMF and is irreversible

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