摘要:
A vibration-type measuring device includes an exciter arrangement which exerts a time-dependent force with at least one sinusoidal component at an adjustable excitation frequency on a measuring tube, through which a medium can flow, and causes the measuring tube to oscillate. The measuring device includes first and second sensors which are fitted to the measuring tube at different locations. The first and second sensors output first and second measurement signals, respectively. The measuring device includes an evaluation unit which determines a first phase shift between the first and second measurement signals and uses the determined phase shift to determine a measurement variable of the medium. The measuring device includes a phase comparator, which determines a second phase shift between the force and the average value of the first and second measurement signals, and a frequency generator which sets the excitation frequency on the basis of the second phase shift.
摘要:
A vibration-type measuring device includes an exciter arrangement which exerts a time-dependent force with at least one sinusoidal component at an adjustable excitation frequency on a measuring tube, through which a medium can flow, and causes the measuring tube to oscillate. The measuring device includes first and second sensors which are fitted to the measuring tube at different locations. The first and second sensors output first and second measurement signals, respectively. The measuring device includes an evaluation unit which determines a first phase shift between the first and second measurement signals and uses the determined phase shift to determine a measurement variable of the medium. The measuring device includes a phase comparator, which determines a second phase shift between the force and the average value of the first and second measurement signals, and a frequency generator which sets the excitation frequency on the basis of the second phase shift.
摘要:
A measuring instrument to capture a physical/chemical measured value, including a sensor unit, which is linked via a contactless interface to a transmitter unit, for passing on to a central analysis unit, wherein the sensor unit includes an at least partly internal sensor element which vibrates against a sensor housing because of operation, and which is linked, contactlessly and inside the sensor unit, for sensor signal transmission, via a first transmission/reception unit, to a complementary second transmission/reception unit, which is arranged at a fixed location relative to the sensor housing, and which is also linked, contactlessly and outside the sensor unit, to a third transmission/reception unit of the transmitter unit.
摘要:
The disclosure relates to a Coriolis mass flowmeter with an oscillatable straight measuring tube consisting of a corrosion-resistant metal, in particular of titanium or a titanium alloy, to which are attached mounted parts connected directly to the measuring tube for the implementation of the Coriolis measurement principle. Furthermore, stabilizing elements running parallel to the measuring tube are coupled to the measuring tube via mounted parts connected directly to the measuring tube, the mounted parts and the stabilizing elements consisting of a metal other than that of the measuring tube. The stabilizing elements are manufactured from a second material which possesses a coefficient of thermal expansion adapted to the metal of the measuring tube. The mounted parts connected directly to the measuring tube are manufactured from a third material which possesses a higher coefficient of thermal expansion than the metal of the measuring tube.
摘要:
A method is disclosed for producing a connection between a measuring tube and at least one flange, e.g., in the case of a Coriolis mass flowmeter. In order to ensure reliable connection of the components in this case, the measuring tube can be inserted at one end over a portion through a flange bore, such that it projects out of the bore on the other side, and that the projecting end be flared out over the sealing face of the flange.
摘要:
A coriolis mass flow pick-up is disclosed, which can be inserted into a pipeline and has a fluid to be measured flowing through it during operation. The pick-up includes a single measuring pipe, which has an inlet end and an outlet end, an exciter arrangement, which causes the measuring pipe to carry out at least first bending oscillations, and at least two sensors for sensing movement of the measuring pipe. At least two elongate connection parts, which extend freely essentially parallel to the measuring pipe and whose central axes are displaced from the axis of the measuring pipe, are connected on the input side and the output side to the measuring pipe. The connection parts carry out second bending oscillations in the event of an oscillating measuring pipe, with the result that, by the second bending oscillations of the connection parts being superimposed by the oscillations of the measuring pipe, bending forces and torsional moments at the inlet and outlet ends of the measuring pipe are compensated.
摘要:
A method for compensation for influences, which interfere with the measurement accuracy, in measurement devices of the vibration type, comprising a measurement tube through which a fluid medium can flow and which is caused to oscillate mechanically, acting as an oscillation body, by an excitation unit, whose oscillation behavior, which changes as a function of the flowrate and/or the viscosity and/or the density of the fluid medium, is detected by at least one oscillation sensor in order to determine the flowrate, wherein the material strain in the measurement tube is detected by means of at least one sensor, from which an indicator value for the influence causing the material strain is calculated in order to correct the measurement signal, by signal processing, from the indicator value obtained in this way.
摘要:
A measuring instrument to capture a physical/chemical measured value, including a sensor unit, which is linked via a contactless interface to a transmitter unit, for passing on to a central analysis unit, wherein the sensor unit includes an at least partly internal sensor element which vibrates against a sensor housing because of operation, and which is linked, contactlessly and inside the sensor unit, for sensor signal transmission, via a first transmission/reception unit, to a complementary second transmission/reception unit, which is arranged at a fixed location relative to the sensor housing, and which is also linked, contactlessly and outside the sensor unit, to a third transmission/reception unit of the transmitter unit.
摘要:
A method is disclosed for producing a connection between a measuring tube and at least one flange, e.g., in the case of a Coriolis mass flowmeter. In order to ensure reliable connection of the components in this case, the measuring tube can be inserted at one end over a portion through a flange bore, such that it projects out of the bore on the other side, and that the projecting end be flared out over the sealing face of the flange.
摘要:
The disclosure relates to a vibration-type measuring device for measuring at least one process variable, in particular a mass flow rate, a density, a viscosity, a pressure or the like, in particular in a process line through which a medium can flow, which device comprises at least one measurement sensor which provides a measurement signal that can be influenced by the process variable, the measured value determined for the process variable by the measuring device being able to be determined from a functional relationship in conjunction with measurement parameters from the measurement signal, and the measurement parameters having a temperature-dependent cross-sensitivity with respect to the temperature distribution in the measuring device. The measuring device comprises at least one temperature sensor, by means of which the local temperature can be measured, and a temperature distribution field can then be calculated with electronic means using a temperature distribution theorem, and correction values for compensating for the temperature-dependent cross-sensitivities of the measurement parameters can be determined from the temperature field data.