EP 0986739 A1 20000322 - METHOD FOR MEASURING A MASS FLOW RATE AND CORRESPONDING DETECTOR
Title (en)
METHOD FOR MEASURING A MASS FLOW RATE AND CORRESPONDING DETECTOR
Title (de)
VERFAHREN ZUM MASSEDURCHFLUSS-MESSEN UND ENTSPRECHENDE AUFNEHMER
Title (fr)
PROCEDE DE MESURE DE DEBIT-MASSE ET CAPTEUR CORRESPONDANT
Publication
Application
Priority
- EP 99917901 A 19990329
- EP 9902134 W 19990329
- EP 98106146 A 19980403
Abstract (en)
[origin: WO9951946A1] The invention relates to a method which applies the clamp-on construction principle to coriolis-type mass flowmeters and detectors. A first and a second decoupling body (4, 5; 4', 5') with identical masses are fixed on a pipeline or a meter tube (1', 10, 10', 10'') at a distance L away from each other in order to define the segment of tube (11; 11'; 11'') which will form the measuring section. The masses of said decoupling bodies are significantly greater than the mass of the tube segment. For two meter tubes, clamping bodies (111, 112; 111', 112') are used. An exciter arrangement (12) is mounted in the centre of the tube segment. This exciter arrangement causes the tube segment to vibrate, the vibrations being of a third vibration mode with a frequency (f) of between 500 Hz and 1000 Hz. The distance L is calculated according to the following formula: L = 5,5 . 2<1/2> . (2 pi f)<-1/2> . {E(r<4>a-r<4>i)/(dM + dF)}<-1/4>, (ra,ri = the outer or inner diameter of the tube segment, E = the elasticity modulus of the tube segment, dM = the density of the material of the tube segment multiplied by its cross-sectional area, dF = the average density of the fluid multiplied by the cross-sectional area of the clear width of the tube segment). Two sensor elements (13, 14) are fixed on the tube segment at the point where a deformation of the tube segment resulting from the interference from the pipeline during excitation in the third vibration mode has a first or a second zero point.
IPC 1-7
IPC 8 full level
G01F 1/84 (2006.01)
CPC (source: EP US)
G01F 1/8409 (2013.01 - EP US); G01F 1/8413 (2013.01 - EP US); G01F 1/8418 (2013.01 - EP US); G01F 1/8422 (2013.01 - EP US); G01F 1/849 (2013.01 - EP US); G01F 1/8495 (2013.01 - EP US)
Citation (search report)
See references of WO 9951946A1
Designated contracting state (EPC)
CH DE DK ES FR GB IT LI NL
DOCDB simple family (publication)
WO 9951946 A1 19991014; CN 1192214 C 20050309; CN 1263596 A 20000816; EP 0986739 A1 20000322; JP 2000513454 A 20001010; JP 3188483 B2 20010716; US 6360614 B1 20020326
DOCDB simple family (application)
EP 9902134 W 19990329; CN 99800459 A 19990329; EP 99917901 A 19990329; JP 55000399 A 19990329; US 28340199 A 19990401