EP1889011A1 - Debitmetre de masse - Google Patents

Debitmetre de masse

Info

Publication number
EP1889011A1
EP1889011A1 EP05749120A EP05749120A EP1889011A1 EP 1889011 A1 EP1889011 A1 EP 1889011A1 EP 05749120 A EP05749120 A EP 05749120A EP 05749120 A EP05749120 A EP 05749120A EP 1889011 A1 EP1889011 A1 EP 1889011A1
Authority
EP
European Patent Office
Prior art keywords
measuring tube
chamber
medium
mass flowmeter
tube
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP05749120A
Other languages
German (de)
English (en)
Inventor
Jens Simonsen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Publication of EP1889011A1 publication Critical patent/EP1889011A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
    • G01F15/02—Compensating or correcting for variations in pressure, density or temperature
    • G01F15/022—Compensating or correcting for variations in pressure, density or temperature using electrical means
    • G01F15/024—Compensating or correcting for variations in pressure, density or temperature using electrical means involving digital counting
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/76—Devices for measuring mass flow of a fluid or a fluent solid material
    • G01F1/78—Direct mass flowmeters
    • G01F1/80—Direct mass flowmeters operating by measuring pressure, force, momentum, or frequency of a fluid flow to which a rotational movement has been imparted
    • G01F1/84—Coriolis or gyroscopic mass flowmeters
    • G01F1/8409—Coriolis or gyroscopic mass flowmeters constructional details
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/76—Devices for measuring mass flow of a fluid or a fluent solid material
    • G01F1/78—Direct mass flowmeters
    • G01F1/80—Direct mass flowmeters operating by measuring pressure, force, momentum, or frequency of a fluid flow to which a rotational movement has been imparted
    • G01F1/84—Coriolis or gyroscopic mass flowmeters
    • G01F1/8409—Coriolis or gyroscopic mass flowmeters constructional details
    • G01F1/8413—Coriolis or gyroscopic mass flowmeters constructional details means for influencing the flowmeter's motional or vibrational behaviour, e.g., conduit support or fixing means, or conduit attachments
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/76—Devices for measuring mass flow of a fluid or a fluent solid material
    • G01F1/78—Direct mass flowmeters
    • G01F1/80—Direct mass flowmeters operating by measuring pressure, force, momentum, or frequency of a fluid flow to which a rotational movement has been imparted
    • G01F1/84—Coriolis or gyroscopic mass flowmeters
    • G01F1/845—Coriolis or gyroscopic mass flowmeters arrangements of measuring means, e.g., of measuring conduits
    • G01F1/8468—Coriolis or gyroscopic mass flowmeters arrangements of measuring means, e.g., of measuring conduits vibrating measuring conduits
    • G01F1/849—Coriolis or gyroscopic mass flowmeters arrangements of measuring means, e.g., of measuring conduits vibrating measuring conduits having straight measuring conduits

Definitions

  • the invention relates to a mass flow meter which operates according to the Coriolis principle, with at least one substantially straight measuring tube leading to a flowing medium according to the preamble of claim 1.
  • Mass flow meters with only a single straight Coriolis measuring tube have become increasingly popular. According to the Coriolis principle mass flowmeters, which have only a single straight measuring tube, have significant advantages over those with two straight measuring tubes or a loop-shaped measuring tube. Namely, no flow divider and flow merge are needed, or a straight measuring tube is easier to produce than a loop-shaped. In addition, the pressure drop is lower and a straight measuring tube can be cleaned more easily.
  • Mass flowmeters with two straight measuring tubes the oscillating parts are identically designed and arranged and vibrated so that they oscillate against each other. This ensures that the center of gravity of the system remains stationary and thus the oscillating system is not effective to the outside. Consequently, no vibrations are introduced into a piping system incorporating such a mass flowmeter. Likewise affect vibrations, which from the. Piping system are introduced into the meter, the measurement result to a lesser extent. Since this is not possible with a mass flowmeter with a single straight measuring tube, complex compensation methods are necessary. From EP 0 317 340 B1 a mass flow meter with a single straight measuring tube is known.
  • each mass body are attached to the two ends of the measuring tube, which are intended to cause at the ends of the measuring tube vibration nodes with little radial movement.
  • a bellows is additionally provided which is intended to prevent thermal expansions due to temperature changes from leading to changes in the mechanical stress conditions in the measuring tube, thus influencing the measurement result.
  • Mass flowmeter caused disadvantageously a relatively high production cost.
  • Another mass flow meter which operates according to the Coriolis principle and has a straight measuring tube is known from EP 0 837 303 A1.
  • the measuring tube is arranged in a chamber which is filled with an incompressible liquid, for example oil.
  • an incompressible liquid for example oil.
  • a pressure compensation membrane In the area of one end of the measuring tube there is a pressure compensation membrane. Since there are hardly any pressure differences between the interior and the surroundings of the measuring tube in the area of the chamber, it is possible to use a thin and thus flexible measuring tube, even if a mass flow rate under high pressure is to be measured. Adversely, however, there is a strong vibration coupling between measuring tube and the pipe in which the mass flow device is installed at the firmly clamped end of the measuring tube.
  • the invention is based on the object
  • Mass flowmeter that works on the Coriolis principle to create, which is good at Measuring accuracy characterized by a relatively low production cost.
  • the invention has the advantage that no axial forces via pipe or housing, for example caused by temperature fluctuations, are introduced into the measuring tube. This is achieved in particular by the fact that the two pipe ends do not serve to support the measuring tube.
  • the storage of the measuring tube is namely arranged between the two pipe ends at an axial distance from them.
  • the pipe ends are thus free floating, the measuring tube can expand with temperature changes and there are no changes in the internal mechanical stress conditions.
  • the arrangement of the bearing at an axial distance from the tube ends also prevents mechanical vibrations of the pipeline system, in which the mass flowmeter is installed, from being coupled into the measuring tube via the tube ends. This also has a positive effect on the measuring accuracy.
  • a pressure equalization between the interior and the surroundings of the measuring tube is achieved in an advantageous manner.
  • the pressure of the medium flowing through the measuring tube has no influence on the mechanical
  • a measuring tube can be used which has a comparatively thin tube wall. This makes the measuring tube more flexible, has a higher sensitivity to Coriolis forces and greater insensitivity to external disturbances.
  • the mass flow meter can use a more flexible Metering tube are operated with lower power consumption.
  • the chamber in which the measuring tube is mounted can be divided into at least two chamber spaces, wherein a first chamber space is provided with the opening for supplying the medium and in this is the first end of the measuring tube and wherein a second chamber of the chamber the opening is provided for the discharge of the medium and in this is the second end of the measuring tube.
  • a substantially tubular chamber which is arranged concentrically to the measuring tube, has the advantage that a particularly simple construction of the chamber is achieved, which is associated with a comparatively low production cost.
  • at least a first bearing of the measuring tube can be formed by a substantially disk-shaped membrane, which is arranged with its plane transverse to the longitudinal axis of the measuring tube, in its center carries the measuring tube and the two chamber spaces sealingly separate from each other.
  • a membrane is relatively stiff in the radial direction, but allows small displacements in the axial direction and a rotation of the measuring tube to a limited extent.
  • the membrane additionally fulfills the function of sealing the two chamber spaces so that no part of the medium guided through the mass flowmeter can flow past the measuring tube.
  • the membrane advantageously also permits torsions and axial displacements of the measuring tube to a greater extent, it can be provided with impressed, concentric waves as a profile.
  • the vibration generator can be arranged in the region of the axial center of the measuring tube.
  • two bearings are provided, which are located substantially in the region of the vibration nodes. This has the advantage that oscillations do not or only to a small extent propagate outward over the bearings, since vibration nodes are characterized by the property that no displacement of the measuring tube takes place in the radial direction.
  • the measuring tube has a hollow cylindrical shape with a constant cross-section.
  • the arrangement of the bearings is advantageously chosen so that they are each axially 20 to 25% of the measuring tube length of the adjacent end of the measuring tube axially removed, since in these areas are the two nodes of the first bending mode.
  • the two bearings can be formed in a simple manner as concentric to the measuring tube, disc-shaped membranes, each secured with its outer edge to the inside of the chamber and carry in their respective center the measuring tube, one of the two membranes preferably medially permeable is.
  • a symmetrical construction of measuring tube and storage is achieved and allows a good balance of the vibration system.
  • the pressure drop which arises in the case of a medium flowing through the measuring tube over the length of the measuring tube leads to an axial displacement of the measuring tube. This pressure drop is dependent on the flow rate and the viscosity of the flowing medium. If the axial displacement is detected by a measuring device, the viscosity of the medium can advantageously be calculated. In addition, a monitoring of the pipe bearings and a diagnosis is made possible, whether the measuring tube still mounted axially displaceable is or already faulty abuts with one of its two pipe ends on the chamber inner wall.
  • a use of the mass flowmeter for measuring the mass flow of a gaseous medium has the advantage that the measurement result is hardly influenced by the medium, which also fills the cavities in the chamber and thus in the environment of the measuring tube.
  • Figure 1 is a schematic diagram of a sensor for a mass flow meter
  • FIG. 2 shows a diagram for clarifying the oscillation deflection in the first bending mode of FIG.
  • FIG. 1 shows a sensor of a mass flowmeter is shown in a longitudinal section.
  • a flowing medium is, as shown by arrows 12 and 13, fed through a feed opening 9 of a chamber 14 and flows out through a discharge opening 10 out of the chamber 14 again.
  • a measuring tube 4 is arranged, which is supported by two membranes 5 and 6 axially floating.
  • the measuring tube 4 is excited by a vibration generator 3, which is located approximately in the central region of the measuring tube 4, to oscillate transversely to a longitudinal axis 22 of the measuring tube 4.
  • the deflection of the measuring tube 4 is detected with two transducers 1 and 2.
  • Vibration generator 3 and transducers 1 and 2 are connected to a control and evaluation, which is not shown for clarity in the drawing.
  • the signals generated with the transducers 1 and 2 are evaluated in terms of amplitude and phase.
  • a first end 15 of the measuring tube 4 is arranged opposite the opening 9 for the supply of the medium such that a free gap between the end 15 and the chamber inner wall remains.
  • a second end 16 of the measuring tube 4 opposite the opening 10 for discharging the medium.
  • a gap between the pipe end 16 and the inner wall of the chamber 14 is left.
  • the two membranes 6 and 7 are designed as corrugated membranes were impressed in the concentric waves, which allow a displacement of the measuring tube 4 in the axial direction and a rotation about the diaphragm center.
  • the membrane 6 is sealingly inserted between the measuring tube 4 and chamber inner wall, so that two separate spaces 18 and 19 of the chamber 14 are formed. This prevents that a part of the medium can flow around the measuring tube 4.
  • the resulting due to a flow through the measuring tube 4 pressure drop is thus on the membrane 6 and leads to an axial displacement of the measuring tube 4, which can be evaluated for viscosity calculation.
  • a pickup 17 the size of the gap between the pipe end
  • the medium temperature can be determined as a process variable and output for processing or message.
  • the two membranes 5 and 6 as bearings of the measuring tube 4 are each 20 to 25% of the measuring tube length of the respective adjacent end 15 and 16 of the measuring tube 4 axially away. In this range at about 22.5% there are nodes of the first bending mode of the measuring tube 4, to which the measuring tube 4 is excited by the vibrator 3.
  • a vibration node is characterized by the property that the measuring tube 4 experiences no deflection in the radial direction at this point. Due to the two gaps between the first end 15 and the second end 16 of the measuring tube 4 and the respective opposite inner wall of the chamber 14, a thermal expansion of the measuring tube 4 is allowed without changing its mechanical stress conditions. Furthermore, it is ensured by the column that vibrations practically not from the measuring tube 4 on a pipeline, in which the transducer is installed, are transmitted. Even vibrations of the pipeline are hardly coupled into the measuring tube 4 and can thus influence the measurement result only to a small extent. The measurement result thus does not depend on axial forces in the pipeline, since no such forces are transmitted to the measuring tube 4.
  • the shown construction of the transducer offers the advantage that the measuring tube is perfectly balanced for all media densities, since the position of the nodes of the measuring tube 4 is practically independent of the density of the medium.
  • the measurement is independent of the pressure of the medium, as over the wall of the transducer
  • Measuring tube 4 no pressure differences fall off.
  • the construction shown additionally has the advantage of simultaneously measuring the mass flow rate, the density of the medium, its temperature and its viscosity allows. He is associated with a relatively low production cost.
  • the sensor is particularly suitable for measuring the mass flow rate of gaseous media, since the environment of the measuring tube 4 filled with the same medium influences the oscillations only to a small extent.
  • FIG. 2 shows two bending lines 20 and 21 of the measuring tube in the first bending mode over the normalized measuring tube length. It is clear that two
  • Vibration nodes are about 0.225 and 0.775 of the measuring tube length.
  • the storage of the measuring tube is provided at this node, since there is no deflection of the measuring tube axis and thus no shift in the radial direction.
  • the course of the bending lines 20 and 21 is mirror-symmetrical to a plane which extends at half of the measuring tube length perpendicular to its longitudinal axis. Due to the Coriolis forces that arise at a mass flow through the measuring tube, these oscillations, an oscillation about the manner of the second bending mode, which is point-symmetrical to a point at half of the measuring tube length, superimposed on the bending lines 20 and 21. The resulting phase shift of the oscillation can easily be detected and evaluated by the transducers 1 and 2 shown in FIG.

Landscapes

  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Volume Flow (AREA)

Abstract

L'invention concerne un débitmètre de masse fonctionnant selon le principe de Coriolis. Un tube de mesure (4) est logé dans une cavité (14) dotée d'au moins deux orifices (9, 10) pour amener et évacuer le milieu relativement à l'extrémité (15, 16) correspondante du tube de mesure (4), dont les supports, entre les deux extrémités (15, 16), sont situés en un espacement axial par rapport à celles-ci, se trouvant de préférence dans un noeud de vibration du premier mode de flexion. Les supports étant positionnés à une distance axiale des extrémités du tube, les dilatations thermiques n'ont pratiquement pas d'influence sur les tensions mécaniques internes du tube de mesure (4) et, par conséquent, n'influencent pratiquement pas les mesures effectuées. Ce débitmètre de masse est avantageusement utilisé pour des milieux gazeux.
EP05749120A 2005-06-01 2005-06-01 Debitmetre de masse Withdrawn EP1889011A1 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP2005/005889 WO2006128483A1 (fr) 2005-06-01 2005-06-01 Debitmetre de masse

Publications (1)

Publication Number Publication Date
EP1889011A1 true EP1889011A1 (fr) 2008-02-20

Family

ID=35825401

Family Applications (1)

Application Number Title Priority Date Filing Date
EP05749120A Withdrawn EP1889011A1 (fr) 2005-06-01 2005-06-01 Debitmetre de masse

Country Status (3)

Country Link
US (1) US7690269B2 (fr)
EP (1) EP1889011A1 (fr)
WO (1) WO2006128483A1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9080908B2 (en) * 2013-07-24 2015-07-14 Jesse Yoder Flowmeter design for large diameter pipes
US20150153210A1 (en) * 2013-12-04 2015-06-04 Gilbarco Inc. Fuel dispenser coriolis flow meter
NL2016092B1 (en) * 2016-01-14 2017-07-24 Berkin Bv Coriolis flowsensor.
US10393560B2 (en) * 2017-03-03 2019-08-27 General Electric Company Mass flow meter including a flexible plate

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2215607B1 (fr) 1973-01-30 1976-04-09 Bertin & Cie
DE3632851A1 (de) 1986-09-26 1988-04-07 Flowtec Ag Nach dem coriolisprinzip arbeitendes massendurchflussmessgeraet
GB2212613B (en) 1987-11-19 1991-07-03 Schlumberger Ind Ltd Improvements in single vibrating tube transducers
US5323658A (en) * 1992-06-19 1994-06-28 Fuji Electric Co., Ltd. Coriolis mass flowmeter
US5691485A (en) 1994-06-06 1997-11-25 Oval Corporation Coaxial double tube type Coriolis flowmeter
FR2754597B1 (fr) 1996-10-15 1998-12-24 Schlumberger Cie Dowell Debitmetre fonde sur l'exploitation des forces de coriolis
DE19825775A1 (de) * 1997-10-07 1999-05-12 Krohne Ag Massendurchflußmeßgerät
US5979246A (en) * 1998-02-09 1999-11-09 Micro Motion, Inc. Spring rate balancing of the flow tube and a balance bar in a straight tube Coriolis flowmeter
US5987999A (en) * 1998-07-01 1999-11-23 Micro Motion, Inc. Sensitivity enhancing balance bar
US6397684B1 (en) * 1999-02-23 2002-06-04 Micro Motion Inc. Low thermal stress case connect link for a straight tube Coriolis flowmeter
DE10003784B4 (de) * 1999-12-27 2004-12-09 Krohne Ag Coriolis-Massendurchflußmeßgerät
US7040179B2 (en) * 2002-12-06 2006-05-09 Endress+ Hauser Flowtec Ag Process meter

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2006128483A1 *

Also Published As

Publication number Publication date
US20090126509A1 (en) 2009-05-21
WO2006128483A1 (fr) 2006-12-07
US7690269B2 (en) 2010-04-06

Similar Documents

Publication Publication Date Title
EP0473919B1 (fr) Dispositif pour la mesure et le dosage des débits massiques
DE3632851C2 (fr)
EP2739944B1 (fr) Procédé de détection d'un dépôt ou d'une abrasion dans un débitmètre
EP1760436B1 (fr) Débitmètre à ultrasons
EP2375224B1 (fr) Dispositif de mesure des ultrasons et procédé de mesure de la vitesse d'écoulement d'un liquide
DE3886946T2 (de) Turbulenzsensor mit taumelnd gelagerter zunge.
EP2705334B1 (fr) Capteur de mesure de type vibratoire et système de mesure formé avec ce capteur de mesure
EP2516972B1 (fr) Capteur de mesure du type à vibrations
DE19908072C2 (de) Massendurchflußmeßgerät
EP0596178B1 (fr) Débimètre massique selon le principe de Coriolis
DE102011010178A1 (de) Coriolis-Massedurchflussmessgerät
DE102010030340A1 (de) Coriolis-Massenstrommessgerät
EP2406588B1 (fr) Capteur de mesure à vibration et instrument de mesure en ligne muni d'un tel capteur de mesure
DE69533747T2 (de) Coriolisdurchflussmesser
EP2614337A1 (fr) Procédé de détection d'un engorgement dans un débitmètre à effet coriolis
EP4085235B1 (fr) Système de mesure vibronique
DE102009055069A1 (de) Meßaufnehmer vom Vibrationstyp
EP1889011A1 (fr) Debitmetre de masse
WO2020002315A1 (fr) Dispositif de mesure servant à définir le débit d'un fluide traversant un tronçon de tube
EP3922972A2 (fr) Dispositif de mesure de la pression d'un fluide circulant dans une tuyauterie
EP1651931A1 (fr) Debitmetre massique
WO2009050133A1 (fr) Appareil de mesure de débit massique et procédé de fabrication d'un cadre raidisseur pour un appareil de mesure de débit massique
DE102017001049A1 (de) Wirkdruckgeber
EP1914526B1 (fr) Capteur de mesure du type de vibration
DE102009046043A1 (de) Messwandler vom Vibrationstyp

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20071204

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

RBV Designated contracting states (corrected)

Designated state(s): DE FR GB

DAX Request for extension of the european patent (deleted)
17Q First examination report despatched

Effective date: 20130212

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: SIEMENS AKTIENGESELLSCHAFT

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: SIEMENS AKTIENGESELLSCHAFT

18D Application deemed to be withdrawn

Effective date: 20140103