Abstract: A method of manufacturing an electromagnetic flow sensor having a measuring tube with an insulating liner having a reinforcing body embedded therein includes the steps of producing the liner in situ in a support tube, and forming a sintering space in the support tube by inserting a sintering mandrel therein. The support tube is closed, leaving one filling aperture for a granular material to be sintered. The reinforcing body is formed in the support tube such that it fits its lumen, by introducing the material to be sintered into the sintering space, sintering, and removing the mandrel. A casting space is formed in the support tube by fixing a casting mandrel therein, and leaving one casting aperture for a liquefied insulting material. The liner is formed by introducing the insulating material into the casting space, allowing to penetrate into the reinforcing body, and solidify in the support tube lumen.

Abstract: Such an excitation circuit is intended for use in a Coriolis mass flowmeter which is connected to, is powered exclusively from, and outputs a measurement signal exclusively via, a two-wire process control loop. The Coriolis mass flowmeter has a vibrating flow tube and an excitation assembly for vibrating the flow tube at a frequency equal or adjacent to the instantaneous mechanical resonance frequency of the flow tube. It further comprises transducer assemblies which are positioned at a given distance from each other along the flow tube and provide respective transducer signals.

Abstract: A vibration meter and a method of measuring a viscosity of a fluid flowing through a pipe are disclosed. The vibration meter comprises meter electronics and a transducer assembly with an electromechanical excitation arrangement and with a flow tube which oscillates in operation. A sensor arrangement produces sensor signals representative of inlet-side and outlet-side deflections of the flow tube. An evaluation circuit derives from said sensor signals and from an excitation current generated by an excitation circuit for the excitation arrangement a viscosity value representative of the viscosity of the fluid.

Abstract: A Coriolis mass flow/density sensor is provided. The sensor includes a measuring tube for conducting a fluid. The measuring tube is fixed in a support and may be coupled to a pipe via an inlet tube and an outlet tube. The sensor further includes an excitation arrangement for vibrating the measuring tube in a predetermined vibration mode, a sensor arrangement for detecting vibrations of the measuring tube, and a brake assembly coupled to the measuring tube and the support. The brake assembly is operable to suppress at least one mode of vibrations other than the predetermined vibration mode.

Abstract: The flowmeter comprises a flow sensor with a flow tube, two electrodes, and two field coils traversed by a first excitation current and a second excitation current, respectively, as well as control and evaluation electronics. The method serves to generate an error signal when the uniform turbulence in the liquid to be measured is disturbed. There are four quarter cycles. During each quarter cycle, a voltage is derived from the electrodes, and from these voltages, a first and a second voltage difference and a quotient using the first and the second voltage differences are formed. The latter is determined during calibration under uniformly turbulent flow conditions, and stored. In operation, values of the quotient are continuously formed and compared with the stored quotient; in case of deviations, an alarm is triggered and/or the volumetric flow rate signal represented by the first voltage difference is corrected.

Abstract: An electromagnetic flow sensor for a fluid flowing through a pipe comprises a measuring tube which can be inserted into a pipe. The measuring tube comprises a support tube as an outer covering of the measuring tube, a tubular liner of insulating material, located in a lumen of the support tube, for conducting the flowing fluid isolated from the support tube, and an open-pore reinforcing body for stabilizing the liner. The reinforcing body is sintered directly in said support tube. A magnetic-circuit arrangement is disposed on the measuring tube for producing and guiding a magnetic field which induces an electric field in the flowing fluid. Electrodes pick up voltages from the electric field. Furthermore, the reinforcing body has coil-core seats for coil cores of the magnetic-circuit arrangement.

Abstract: By means of this process it is intended to achieve a high mechanical-geometric accuracy of bent tubes, and it is used for bending a measuring tube for a Coriolis mass flow rate sensor by means of a tube section of a predetermined length and by means of a two-piece press mold, which has been matched to both the measuring tube, which has an inner diameter and an outer diameter, and to the desired shape. To this end, a flexible support body is inserted into the tube section, which is fastened in a first end of the tube section in such a way, that the end is closed, and whose maximum outer diameter is less than the inner diameter of the tube section. The tube section is filled with a liquid which is subsequently permitted to solidify completely. The tube section filled with the support body and the solidified liquid is placed into the opened press mold, the latter is closed and the tube section is bent into the desired shape by this. The press mold is opened and the bent tube section is removed.

Abstract: The electronic apparatus (1) has an enclosure (10), which has a terminal compartment (12) and an electronics compartment (11). These two compartments are separated by an internal wall (13) which has a longitudinal slot (131) of depth T in which a bushing (14) is fitted. The bushing is to be flameproof designed. To this the enclosure (10) comprises: 1) A baseboard (141) which extends into and is mounted in the electronics compartment, has a stop (142), and can be fitted with electronic components (143); 2) a lead arrangement (144) extending into the terminal compartment (12) and contacting the components on the baseboard; and 3) a plastic part (146) which surrounds the lead arrangement, is formed integrally with the stop (142), and has the shape of, and thus fills, the longitudinal slot (131).

Abstract: The current-regulator circuit generates a supply current by means of clocked setting electronics and by means of control electronics which deliver a pulse-width-modulated clock signal. The setting electronics comprise a storage choke and a smoothing capacitor coupled thereto. By means of two electronic switches of the setting electronics, a first potential and a second potential are applied alternately to the storage choke, so that a current flowing through the storage choke has an AC component flowing through the smoothing capacitor and a DC component flowing through the excitation circuit, the DC component serving as supply current. The current-regulator circuit proposed is particularly suitable for use in an intrinsically safe and/or field-bus-enabled electromagnetic flowmeter.

Abstract: This mass flow/density sensor (10), which can be installed in a pipe and through which a fluid to be measured flows during operation, is to be balanced over a wide density range, so that accurate measurements are possible. A single straight measuring tube (13) having a longitudinal axis (131) extends between its inlet end (11) and the outlet end (12) and is fixed to a support, e.g., a cylindrical tube (14, 14′). The support has a longitudinal centroidal line (141) which is parallel to, but does not coincide with, the longitudinal axis (131) of the measuring tube. A cantilever (15) is fixed to the measuring tube (13) midway between the inlet and outlet ends (11, 12) and in operation causes the measuring tube to vibrate either in a first fundamental flexural mode or in a second fundamental flexural mode having a higher frequency than this first mode. An excitation arrangement (16) disposed midway between the end pieces excites the measuring tube (13) in the second mode.

Abstract: The accuracy of this method is comparable to that of the measurement of liquids. The fluid flows through at least one flow tube (4) of a mass flow sensor (1) of a Coriolis mass flow/density meter, which flow tube vibrates at a frequency f being equal to or in the vicinity of the instantaneous mechanical resonance frequency of the flow tube (4) having a vibrator (16). A first and second vibration sensor (17, 18) are attached to the flow tube, deliver a first and a second sensor signal (x17, x18), and are positioned at a given distance from each other in the direction of flow. The flow tube (4) is surrounded by a support frame or a support tube (15) or held by a support plate so as to be capable of vibrating. The sensor signals (x17, x18) have a phase difference from which a signal qf is formed; it is multiplied by a function f(c) dependent on the speed of sound c in the fluid which can be approximated by a function f(Tm) dependent on the current temperature Tm of the flow tube (4).

Abstract: This circuit is suitable for flow tubes (4) the vibration frequency of which is in the order of 1 kHz. A fluid to be measured flows through the tube (4) vibrating in operation at a frequency determined by the density of the fluid. Attached to the tube (4) are electromagnetic vibration sensors (17, 18) positioned at a given distance from each other delivering sinusoidal sensor signals (x17, x18). Impedance-matching devices (31, 32) are fed by the sensor signals. Inputs of an intermediate switch (35) are connected to the outputs of impedance-matching devices. Additional impedance-matching device (33, 34) are fed by outputs of the intermediate switch. Low-pass filters (37, 38) are connected to the outputs of the additional impedance matching devices. The upper cutoff frequency of low-pass filter (37) differs by about 10% to 15% from the upper cutoff frequency of low-pass filter (38). Zero-crossing detector (39, 40) are fed by the outputs of the low-pass filters.

Abstract: A Coriolis mass flow/density sensor which can be installed in a pipe and through which a fluid to be measured flows during operation is balanced over a wide density range so that accurate measurements are possible. The Coriolis mass flow/density sensor includes a measuring tube, an excitation arrangement for exciting the measuring tube to vibrate in a second fundamental flexural mode of vibration; and a counterbalance member attached to the measuring tube which counterbalances the vibration of the measuring tube. A cantilever can be attached to the measuring tube midway between the inlet end and the outlet end of the measuring tube. First and second sensors sense the measuring tube vibration on the inlet and outlet sides of the measuring tube, respectively.

Abstract: These sources are so designed that the amount of power required at turn-on of the DC voltage source is greater than during normal operation, taht the power supply for the evaluation electronics is independent of the measured value, and that the so-called HART protocol can be trans-mitted over the two wires. A first variant of the sources has a first current path, which goes from terminal (P1) via diode (D), the emitter-collector path of transistor (T1), grounded voltage regulator (SR), and grounded current-sensing resistor (Rm) to terminal (P2) of the DC voltage source, and a second current path, which goes from terminal (P1) via diode (D), the emitter-base path of transistor (T1), resistor (R1), the collector-emitter path of transistor (T2), resistor (R2), and resistor (Rm) to terminal (P2). Feedback resistor (Rr) connects terminal (P2) to one of the inputs of operational amplifier (OP) fed by a control signal and the output of which being connected to the base of transistor (T2).

Abstract: This method serves to apply the clamp-on design principle to Coriolis mass flow meters and sensors. A first isolating body (4, 4′) and a second isolating body (5, 5′) having identical masses are fixed to the outside of a pipe (1) or a measuring tube (1′, 10, 10′, 10″) at a predetermined distance L from each other to define a measuring length forming a pipe or tube section (11; 11′; 11″). These masses are substantially greater than the mass of the pipe or tube section. If two measuring tubes are present, clamping bodies (111, 112; 111′, 112′) are used. A vibration exciter (12) attached in the middle of the pipe or tube section excites the latter in a third mode of vibration at a frequency f between 500 Hz and 1000 Hz. The distance L is calculated by the following formula: L=5.

Abstract: A single-tube Coriolis mass flow sensor includes a stainless steel sleeve having an unplated interior surface and a titanium member having a cylindrical end inserted into the stainless steel sleeve. The exterior surface of the titanium cylindrical end forms a joint with the unplated interior surface of the stainless steel sleeve. The titanium cylindrical end is brazed to the unplated interior surface of the stainless steel sleeve at the joint, and the stainless steel sleeve exerts compressive stress on the titanium cylindrical end at the joint.

Abstract: This sensor for measuring the flow velocity and/or the flow rate of a fluid provides an optical sensor system which is also suitable for use at temperatures higher than 400° C., does not come into contact with the fluid, and requires less space than conventional optical sensor systems. The sensor comprises a tube (1) through which the fluid flows in a first direction and which has a wall (11) in which a first window (2) and a second window (3) of optical, schlieren-free, high-temperature glass are set fluid-tight and pressure-tight at points lying opposite each other along a first tube diameter. A bluff body (4) is disposed along a second tube diameter and fixed in the tube for generating Kármán vortices, whose frequency f is proportional to the flow velocity u. The second diameter is up-stream of, and perpendicular to, the first.

Abstract: Surprisingly, silver-copper-palladium brazing alloys, which have hitherto been used only for the brazing of components of the same material, are also very well suited for brazing directly titanium to stainless steel if, the latter component clasps the titanium component tightly, so that the cold joint is under constant compressive stress. In a method for forming the titanium-steel compound the titanium component is provided with a cylindrical end which has a smaller outside diameter than an adjacent main portion whose external surface is a first surface to be brazed. The cylindrical steel component is a sleeve whose inside diameter is equal to the outside diameter of the main portion and whose internal surface is a second surface to be brazed. A silver-copper-palladium brazing alloy is placed around the end of the titanium component. The steel sleeve is slipped thereover.

Abstract: To achieve accuracies of the order of 0.75% of the measured value, a digitized, two-dimensional overall image of a bluff body (7), of the internal surface of a measuring tube (2) in the area of the bluff body, of the two fixing zones (71, 72) of the bluff body, and of contour line (51) of the inlet end (5) of the measuring tube is generated by a high-resolution electronic camera (9) located in front of the measuring tube (2) on the axis (3) of this tube. The overall image is divided into three partial images. The first partial image contains only information about the inlet end (5) and the internal surface (4) of the measuring tube, the second contains only information about the bluff body (7) without the fixing zones (71, 72), and the third contains only information about the fixing zones. From shape information about the fixing zones (71, 72) and ideal information characteristic of the ideal shapes of the fixing zones, cross-correlation information is formed.

Abstract: A Coriolis-type mass flow sensor (1) is disclosed which is as insusceptible to external disturbances as possible and which can be installed in a conduit and, during operation, is traversed by a fluid to be measured. The conduit is connected via a fluid inlet (113) and a fluid outlet (114) with a casing (11) in which a rigid support base (12) is disposed. The support base (12) is connected with the casing via at least one mechanical damping element (13, 14, 20). A measuring tube (15) traversed by the fluid ends in the fluid inlet and the fluid outlet. A portion (151) of the measuring tube which is to be set into vibration is attached to the support base by an inlet-side fixing means (121) and an outlet-side fixing means (122). An inlet-side connecting portion (152) of the measuring tube extends from the inlet-side fixing means (121) to the fluid inlet (113), and an outlet-side connecting portion (153) extends from the outlet-side fixing means (122) to the fluid outlet (114).