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 out-side 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: These substitution kits are provided for field-installed volumetric differential pressure flow sensors (101, 102, 103, 104, 105, 106) comprising bores (111, 121) for sensing the fluid pressure and an orifice plate (13) of standard thickness which is fixed fluid-tight between two pipes (1, 2) conducting a fluid to be measured. A first variant of the kit comprises an annular disk (23) which replaces the plate (13) and whose thickness is equal to that of the plate as well as whose opening has a diameter equal to the inside diameter of the pipes. A single bluff body (2311, 2312, 2313, 2314, 2317, 2318, 2319) is arranged in the lumen of the annular disk. The bore (111) of the pipe (1) is fluid-tightly closed by a device (18) after removal of the pressure sensor of the bore (111). A vortex sensing element (19) is inserted fluid-tightly in the bore (121) of the pipe (2) after removal of the sensor of this bore. Acc.

Abstract: In order to raise the measuring accuracy of a Coriolis-type mass flow rate meter in a cost-effective fashion, the latter comprises a measuring tube (4), a subcircuit measuring circuit and a subcircuit exciting circuit. Two vibration sensors (17, 18) and a vibration exciting (16) are arranged on the measuring tube. The vibration sensor (17) is assigned the amplifier (v1) in the subcircuit measuring circuit, and the vibration sensor (18) is assigned the amplifier (v2). Downstream of the two amplifiers are the summing stage (ss1) with a downstream integrating stage (ig), and the difference stage (ds). Downstream of the integrating stage (ig), the difference stage and the amplifier (v1) are the A/D converters (aw1, aw2, aw3), following which the digital processor (dp) is connected; it supplies the digital mass signal (m) and/or the digital density signal (d), as well as the gain control signal (v) for the amplifier (v2).

Abstract: This method of fastening a metal body to a an outer circumference of a single straight measuring tube, consisting of titanium or zirconium, of a Coriolis-type mass flow sensor does not need any heating, for example soldering, welding or brazing, process. The metal body has a circumferential surface and a bore adapted to the outer circumference. The metal body cooperates with an exciter arrangement or with a sensor arrangement or serves as a cantilever mass or as an end piece of the measuring tube. The metal body is pushed on to the measuring tube and is subsequently pressed on to the latter at ambient temperature. A pressure sufficient for fastening but not reducing substantially the lumen of the measuring tube at the fastening position is exerted on at least part of the circumferential surface.

Abstract: This method completely eliminates the detrimental effect of eddy currents on the rise time of the magnetic field, so that it reaches its constant value already when the current assumes its maximum. The field is generated by a current flowing in a coil which forms part of a magnetic system contained in an electromagnetic flow sensor, which comprises a core and/or a pole piece. The current changes periodically its polarity thereby causing the eddy currents. The current flows in a H network of transistors (13, 14, 14, 16) or a T network of switching transistors (25, 26). A resistor (10, 10'; 22, 22') is series connected to the H or T network. In each current half-cycle, an initial voltage during a rise time of the current--as a first subcycle--which is higher than a final voltage during a second subcycle is fed to the coil.

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: This vortex flow sensor is to be designed either as vortex sensor with a capacitive vortex sensing element (3, 3') either arranged in the hole of a bluff body (4) or inserted into a wall opening of a measuring tube (2, 2') downstream of the bluff body. Both vortex sensing elements being of largely identical construction and being capable of being produced as an independent component in the manner of a module. The wall sensor (3) and the bluff body sensor (3') has a diaphragm (33, 33') sealing off the hole and the wall opening. A flexurally stiff thin sensor vane (31) or sensor sleeve (51) and a sleeve-shaped electrode arrangement (34, 34') with at least one electrode (341, 341') are attached to the diaphragm on opposite sides. A housing cap (32, 32') surrounds the electrode arrangement and the diaphragm, is fixed on the measuring tube and contains a second electrode arrangement (35, 35') with at least one counter-electrode (351, 352; 351', 352').

Abstract: To improve both the absolute measurement accuracy and the linearity of the characteristic function and the short-time repeatability of measurements at varying flow velocities, particularly at low flow rates, this electromagnetic flow probe (10) is designed to be immersed in a fluid flowing in a pipe (12), which is to be measured, the direction of immersion being virtually perpendicular to the direction of fluid flow. The probe is further designed to be passed through a hole in a wall of the pipe fluid-tight and comprises a circular cylindrical housing (11) having a predetermined outside diameter adapted to the bore. The front end (14) of the housing extends into the fluid and is closed fluid-tight by a front plate (14") of insulating material in the form of a calotte, which has a radius approximately equal to 1.2 to 1.5 times the outside diameter of the housing. A coil assembly (15) is disposed in the housing for establishing a magnetic field (16) extending through the front plate (14") into the fluid.

Abstract: To increase in the accuracy of vortex flow sensors measuring the flow velocity and/or the volumetric flow rate of a fluid flowing through a measuring tube, the vortex flow sensor comprises a cylindrical bluff body of circular section mounted in the measuring tube. The bluff body has a surface which is roughened. A single vortex-sensing element is responsive to pressure fluctuations caused by the vortices. The roughness can be realized by shallow depressions being identical in shape and either evenly or unevenly, particularly stochastically, distributed over the surface of the bluff body. The depressions can be only provided in a sector of the surface whose central angle is less than 180.degree..

Abstract: This vortex flow sensor (1) for measuring the flow velocity and/or the volumetric flow rate of a fluid flowing in a measuring tube (2) has an improved measurement accuracy according to the following design: A bluff body (4) is mounted in the measuring tube and designed to generate Karman vortices; a vortex-sensing element (5) is responsive to vortex-induced pressure fluctuations; and a turbulence grid (6) is mounted upstream of the bluff body and has openings with at least partially differing cross sections. The turbulence grid cn be circular and formed by radial members and spaced-apart concentric circular members. The turbulence grid can have a thickness D in the direction of flow and be located at a distance x from the bluff body, said thickness and said distance satisfying the inequality: 20D<x<40D.

Abstract: This device (1) produces a steep-fronted liquid pressure wave which strikes a body (12) to be tested with an adjustable table pressure. The device has a measuring tube (10) within or to which the body (12) is fixed, and which has a pressure-proof observation window (13, 14) and a pressure-relief valve (15). A pressure tube (20) with a compression system (25) which compresses a gas is closed on one side by a first diaphragm (29) which forms part of a chamber (27) that is provided with a valve (25). The chamber is closed by a second diaphragm (19) located opposite the diaphragm (29). In tube (10), a piston (18) is movable on guides (17) up to a braking device. To carry out the method, an amount of liquid which only partially fills the tube (10) is applied to the pistons In the chamber (27), a pressure equal to half the bursting strength of the diaphragms (29, 19) is set. The pressure in the tube (20) is increased until the bursting strength is exceeded.

Abstract: Instrumentation amplifier arrangements (10, 10') of electromagnetic flowmeters are disclosed which permit reliable conditioning of the measuring-electrode signals without an increase in coil current even if solids-loaded fluids are measured. The flowmeter has a measuring tube (1) with at least two measuring electrodes (3, 2) and a ground electrode (4) as well as a coil arrangement (5) for producing a magnetic field. A first variant of the instrumentation amplifier arrangement comprises two preamplifiers (11, 12) each connected to a respective one of the two measuring electrodes (3, 2) and followed by a respective ana-log-to-digital converter (13, 14). A clock generator (18) supplies the analog-to-digital converters (13, 14) with a sampling signal whose frequency is greater than approximately 1 kHz. The analog-to-digital converters (13, 14) are followed by a subtractor (17).

Abstract: This Coriolis mass flow sensor (40, 50, 60, 70) can be inserted in a pipeline by means of an inlet-side and an outlet-side connecting element (402, 403; 502, 503; 602, 603; 702, 703). An oscillating system comprises at least one measuring tube (401; 501; 601; 701, 701'), through which a fluid to be measured flows in operation. The oscillations of the oscillating system are excited by means of an electromagnetic exciter arrangement (1, 2, 3, 4, 10) which has at least one low-resistance exciter coil (15; 251, 252; 35) fed from an exciter current source (6, 7), a core (13, 23, 33, 43, 53) containing a permanent magnet (12; 221, 222; 32; 42; 512, 522), and an armature (14, 24, 34, 44, 54, 104). The oscillating system can also be excited by interference vibrations which contain a frequency which is the same as the resonant frequency of the oscillating system, such that the measurement result is corrupted.

Abstract: For the low-cost manufacture of differently dimensioned saddle coils (2) which have good long-term dimensional stability, although because of the thickness of the wire used for the saddle coil, the dimensional stability cannot be achieved with this wire alone, and which fit differently curved surfaces and have a number of turns, use is made of a prefabricated wire having a first insulating-varnish coating directly thereon and a second insulating-varnish coating applied to the first coating, the second coating having a baking temperature lower than the softening point of the first coating. The coil is wound on a coil form (1) to form a flat coil (21), the coil form being a prefabricated part of a flexible plastic which is dimensionally stable at the baking temperature. The flat coil is then fitted, together with the coil form (1), to the curved surface of a corresponding dummy to form a still dimensionally unstable saddle coil.

Abstract: A Coriolis-type mass flow meter is disclosed which can be installed, e.g., via flanges, in a conduit of a given diameter so as to be axially aligned with said conduit, which is traversed by a fluid to be measured. To further improve and optimize its insensitivity to vibrations originating from the conduit, this Coriolis-type mass flow meter comprises: at least one measuring tube fixed to the flanges; a support tube having its ends fixed to the respective flanges; means for exciting the measuring tube into resonance vibrations; velocity sensors positioned along the measuring tube for sensing the vibrations of the measuring tube; acceleration sensors positioned on the support tube along a line of intersection with that plane in which Coriolis forces act; and means which process signals from the velocity sensors and signals from the acceleration sensors into a mass flow signal which is substantially free from interference.

Abstract: A mass flowmeter (1) based on the Coriolis principle is disclosed whose susceptibility to disturbances originating from the conduit, such as vibrations of the conduit or wide pressure variations of the fluid, and to other disturbances, such as impacts on the casing (11), is greatly reduced by mechanical means.

Abstract: Improved Coriolis mass flow sensor including a single connection and support structure having an in-line inlet and outlet and a one-piece, generally helical sensing tube structure wound in concentric fashion about the in-line axis of the support structure and supported relative thereto by tube ends affixed to ports formed in the support structure and in fluid communication with the inlet and outlet flow paths. The tube extends through approximately 720.degree. as it wraps about the centerline axis, and carries actuator means at its 12 o'clock position and sensors at the quarter hour positions on opposite sides of the device centerline. A pair of node plates are disposed at spaced-apart locations on the tube side opposite the actuator and serve to couple the centermost loop section to the downstream tail and the centermost loop section to the upstream tail, respectively.

Abstract: To introduce an insulation (3) of desired thickness into a measuring tube (1) of an electromagnetic flow sensor at low cost forming a tight joint, said measuring tube comprising a metal tube (2) having a respective metal flange (4, 5) at each end (21, 22),the respective metal flange (4, 5) at each end is slipped over the outside (23) of the metal tube in such a way that a front side (41, 51) of the metal flange projects beyond the end of the metal tube by an amount at least equal to the thickness of the insulation (3), and a rear side (45, 55) of the metal flange is permanently and tightly joined to the outside (23) of the metal tube. Before being slipped on, each metal flange is provided, from the front side, with a flute (42, 52) which forms a first annular groove (43, 53) at its inner end. A mandrel whose diameter is determined by the desired thickness of the insulation is introduced into the lumen of the metal tube.

Abstract: In the evaluation electronics of a Coriolis mass flow sensor, two preamplifiers provide output signals that are applied to a fixed gain amplifier and a variable gain amplifier. Outputs from the two gain amplifiers are applied to a difference stage having an output coupled to a changeover switch. The output of the fixed gain amplifier is also coupled to the changeover switch. A summing/integrating stage receives signals from the preamplifiers and is connected to a phase locked-loop followed by a phase measuring and phase adding stage having an output that provides first and second phase shifted signals. A first synchronous rectifier is clocked by the first phase shifted signal and has an output connected to a switch. A sequencer keeps the switch ON during an ON period and switches the changeover switch to the difference stage except during a short measurement period during which the sequencer activates a phase measurement.

Abstract: To measure the average velocity v.sub.m and the flow index N of an electrically conductive non-Newtonian fluid flowing through a measuring tube (11) whose portion coming into contact with the fluid is electrically nonconductive, this electromagnetic flowmeter further comprises: two coils (12, 13) positioned diametrically opposite to each other on the measuring tube which serve to produce a magnetic field when a coil current (i) flows therethrough; electrodes (14, 15) serving to pick off an induced first potential and an induced second potential, with a respective radius (14.sub.1, 15.sub.1) of the measuring tube at the point of each of the electrodes making an angle (.phi.) of less than 90.degree. with the direction of the magnetic field; a coil-current generator (21); a double-pole switch (22) for connecting the two coils either in series aiding or in series opposition; and evaluation electronics (24) which form a velocity signal (S.sub.v) proportional to the average velocity v.sub.