A downhole tool includes a membrane to separate water from a formation fluid and a meter that operates as a densitometer and a Coriolis effect flowmeter.

A vibratory measuring device for determining a mass flow rate or a density of a medium includes: a vibratory measuring tube which is curved when in a rest position; a support body; a first bearing body; a second bearing body; two exciter units and two sensor units; and a circuit. The bearing bodies are connected to the support body such that flexural vibration modes of the measuring tube have vibration nodes on the bearing bodies, wherein the exciter units are configured to excite flexural vibrations of the measuring tube, wherein the sensor units are each configured to detect flexural vibrations of the measuring tube both in and perpendicular to the plane and to output vibration-dependent sensor signals, wherein the circuit is configured to output excitation signals to the excitation units for the selective excitation of flexural vibration modes and to receive the sensor signals of the sensor units.

A measurement tube of a Coriolis sensing element for measuring a density and a mass flow rate of a medium flowing through a measurement tube includes a measurement tube wall and a measurement tube lumen, characterized in that the measurement tube wall has a sintered ceramic material or is produced from a sintered ceramic material.

The invention relates to a micro-Coriolis mass flow sensor, comprising a Coriolis tube having a fixed inlet and a fixed outlet, being fixed in tube fixation means, excitation means for oscillating the Coriolis tube about an excitation axis, detection means (8) for detecting, in use, at least a measure for movements of part of the Coriolis tube, characterized by the detection means (8) comprising one or more strain measurement devices (9, 11) configured for resistive readout being arranged in or on the Coriolis tube.

A vibratory measuring device for determining a mass flow rate or a density of a flowable medium comprises: a vibratory measuring tube which is curved when in the idle position thereof; a support body; a first bearing body on the inlet side; a second bearing body on the outlet side; two exciter units and two sensor units; and an operation and evaluation circuit. The bearing bodies are connected to the support body, wherein the measuring tube is supported on the bearing bodies in such a way that flexural vibration modes of the measuring tube have vibration nodes on the bearing bodies, wherein the exciter units are each configured, according to excitation signals, to excite flexural vibrations of the measuring tube both in the measuring tube plane and perpendicular to the measuring tube plane, wherein the sensor units are each configured to detect flexural vibrations of the measuring tube both in the measuring tube plane and perpendicular to the measuring tube plane and to output vibration-dependent sensor signals, wherein the operation and evaluation circuit is configured to output excitation signals to the excitation units for the selective excitation of flexural vibration modes and to receive the sensor signals of the sensor units.

A downhole tool includes a membrane to separate water from a formation fluid and a meter that operates as a densitometer and a Coriolis effect flowmeter.

The invention relates to a Coriolis flow sensor. The sensor comprises a housing and at least a Coriolis-tube with at least two ends being fixed in a tube fixation means. The flow sensor comprises excitation means for causing the tube to oscillate, as well as detection means for detecting at least a measure of displacements of parts of the tube during operation. According to the invention, the Coriolis flow sensor comprises a reference mass, as well as further excitation means arranged for causing the reference mass to oscillate during operation, as well as further detection means for detecting at least a measure of displacements of the reference mass during operation. Additionally, control means are provided for controlling the excitation means and/or further excitation means based on vibrations measured by the detection means and/or further detection means. This way a Coriolis flow sensor with active vibration isolation is obtained.