Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L27/00—Testing or calibrating of apparatus for measuring fluid pressure
  • G01L27/007—Malfunction diagnosis, i.e. diagnosing a sensor defect
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
  • G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
  • G01F1/34—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by measuring pressure or differential pressure
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
  • G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
  • G01F1/34—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by measuring pressure or differential pressure
  • G01F1/36—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by measuring pressure or differential pressure the pressure or differential pressure being created by the use of flow constriction
  • G01F1/363—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by measuring pressure or differential pressure the pressure or differential pressure being created by the use of flow constriction with electrical or electro-mechanical indication
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F25/00—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume
  • G01F25/10—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume of flowmeters
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L13/00—Devices or apparatus for measuring differences of two or more fluid pressure values
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L13/00—Devices or apparatus for measuring differences of two or more fluid pressure values
  • G01L13/02—Devices or apparatus for measuring differences of two or more fluid pressure values using elastically-deformable members or pistons as sensing elements
  • G01L13/025—Devices or apparatus for measuring differences of two or more fluid pressure values using elastically-deformable members or pistons as sensing elements using diaphragms
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
  • G01L19/0007—Fluidic connecting means
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
  • G01L19/0007—Fluidic connecting means
  • G01L19/0023—Fluidic connecting means for flowthrough systems having a flexible pressure transmitting element
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B2219/00—Program-control systems
  • G05B2219/20—Pc systems
  • G05B2219/24—Pc safety
  • G05B2219/24033—Failure, fault detection and isolation

Definitions

• the present invention relates to a differential pressure measuring arrangement with
• Differential pressure lines and a method for detecting clogged differential pressure lines are used in particular for flow measurement or filter monitoring, depending on a differential pressure line in
• a differential pressure transducer such as a diaphragm or a venturi nozzle, or a filter are connected to a media-carrying line to the differential pressure by means of the medium to a
• Differential pressure transducer to transfer the differential pressure measuring arrangement. During the operation of these measuring arrangements, it can lead to blockages of the differential pressure lines, whereby a reliable measurement is impaired. It is therefore
• German patent application DE 10 2013 1 10 059 A1 describes a
• the object is achieved by the differential pressure measuring arrangement according to claim 1 and the method according to claim 4.
• the differential pressure measuring arrangement comprises: a differential pressure transducer for determining at least one
• Differential pressure value representing a difference between a first media pressure and a second media pressure within a process
• step c) returning to step a) in the event that it is determined that the differential pressure measuring arrangement and / or the process are not in a state that allows a diagnosis of the differential pressure line, wherein in step a) the first differential pressure values are detected again, so that the previously detected first differential pressure values are deleted or overwritten;
• Differential pressure measuring arrangement and / or the process in a state that allows a diagnosis of the differential pressure line are provided.
• the invention is based in principle on the assumption that a process is always subject to noise, which is individual but essentially constant for each process, if the process is in a defined state and in addition that the process may have spurious signals due to disturbing influences. which go beyond the normal noise.
• the process is always subject to noise, which is individual but essentially constant for each process, if the process is in a defined state and in addition that the process may have spurious signals due to disturbing influences. which go beyond the normal noise.
• Differential pressure measuring arrangement are in a state which does not allow a diagnosis of whether an active pressure line is clogged.
• Differential pressure measuring device to be checked before the actual diagnosis, whether there is currently a state that allows a diagnosis. For this is by the
• Differential pressure measuring arrangement and / or the process are in a state that allows no diagnosis, the currently recorded pressure readings are discarded, i. deleted and in particular not saved.
• the diagnostic unit is further configured to check whether the differential pressure measuring arrangement is in a stable state to determine whether the differential pressure measuring arrangement is in a state that allows a diagnosis of the differential pressure line.
• a further advantageous development of the invention provides that the diagnostic unit is further configured to check whether the process has no significant change in order to determine whether the process is in a state that allows a diagnosis of the differential pressure line.
• the invention further relates to a method for the diagnosis of a differential pressure line of a differential pressure measuring arrangement, which according to the invention comprises at least the following method steps:
• step c) returning to step a) in the event that it is determined that the differential pressure measuring arrangement and / or the process are not in a state that allows a diagnosis of the differential pressure line, wherein in step a) the differential pressure values are detected again, so that the previously detected first differential pressure values are deleted or overwritten;
• Differential pressure measuring arrangement and / or the process in a state that allows a diagnosis of the differential pressure line are provided.
• An advantageous embodiment of the method according to the invention provides that for checking whether the differential pressure measuring arrangement and / or the process are in a state which allows a diagnosis of the differential pressure line, it is at least checked whether the differential pressure measuring arrangement is in a stable state.
• the embodiment may provide that for checking whether the
• Differential pressure measuring arrangement is in a stable state, it is checked whether the fixed number of first differential pressure values within a defined first range with a fixed frequency. Furthermore, the embodiment may provide that the defined first area comprises a simple standard deviation that is formed over a fixed number of second differential pressure values. Likewise, the embodiment may provide that the set number of second
• Differential pressure values were detected by the differential pressure measuring arrangement, while the process is in a stable state and / or in the case that the predetermined number of first differential pressure values are not within the defined first range with the predetermined frequency, is returned to step a), In method step a), the first differential pressure values are detected again, so that the previously detected differential pressure values are preferably completely deleted or overwritten.
• a further advantageous embodiment of the method according to the invention provides that for checking whether the differential pressure measuring arrangement and / or the process are in a state which allows a diagnosis of the differential pressure line, it is at least checked whether the process has no significant change.
• the embodiment may provide that for checking whether the process has no significant change, a fixed number of further differential pressure values are detected and an average value is formed over the further differential pressure values, wherein
• the embodiment can provide that the defined second area is defined by an operator or process operator, so that the defined second area can be adapted to the circumstances of the process.
• the embodiment also provides that a defined standard deviation of the previously recorded differential pressure values is used as the defined second range if the operator or process operator has not set a value.
• the three-fold standard deviation has proven to be a suitable compromise between sensitivity and general process noise.
• the embodiment can also provide that, in the case where the mean value is not within the defined second range, the method returns to method step a), wherein a defined number of further differential pressure values is again detected in method step a), wherein preferably the previously detected further differential pressure values are deleted or overwritten and / or that the first time executing at least the method steps a) to b) it is assumed that the process has no significant change.
• Fig. 1 a schematic representation of an inventive
• FIG. 2 shows a flowchart of a method according to the invention.
• Differential pressure measuring arrangement comprises a differential pressure transducer 2, which is a sensor module 1 1, which is arranged between a first, high-pressure side pressure input 4 and a second, low-pressure side pressure input 6, and a
• Sensor module 1 1 powered and processed signals of the sensor module 1 1.
• the electronic module 8 is connected via a two-wire line 9 to a process control system 10, wherein the electronic module 8 is communicated via the two-wire line 9 and supplied with energy.
• the two-wire line 9 can be operated in particular as a field bus according to the Profibus or Foundation Fieldus standard or according to the HART standard.
• Such differential pressure transducers are known per se and are manufactured, for example, under the trademark Deltabar by the applicant and placed on the market.
• the differential pressure measuring arrangement further comprises a
• Differential pressure transducer 12 for installation in a pipeline 13.
• the differential pressure transducer 12 comprises a diaphragm 14, a first pressure tap channel 15 on a high pressure side of the diaphragm 14 and a second pressure tap channel 16 on a low pressure side of the diaphragm 14.
• the first high pressure side pressure input 4 is on a first harnessd backside
• Differential pressure line 3 connected to the high-pressure side pressure tap channel 15, and the second low-pressure side pressure input 6 is connected via a second low-pressure side
• Differential pressure line 5 connected to the low-pressure D ruckabgriff channel 16 connected.
• high-pressure side and low-pressure side refer to a pressure difference generated by a flow (in the drawing from left to right), which is proportional to the square of the flow rate and is for example in the order of several tens to 100 mbar.
• the static pressure, which is superimposed on this flow-dependent pressure difference, can be, for example, from 1 bar to several 100 bar.
• the pressure difference is detected with a sensor element of the sensor module 1 1, wherein the sensor module 1 1 outputs a dependent of the detected pressure difference sensor module signal to the electronic module 8, wherein a processing circuit of the
• Time series of the differential pressure value can be in one Data memory of the electronic module 8 and / or stored in the process control system 10.
• the data memory is designed such that it can store a defined number of differential pressure values.
• the data memory can be designed such that it can receive 100 differential pressure values, so that these are kept ready for further processing.
• the data memory is in the form of a ring memory.
• the differential pressure measuring arrangement comprises a diagnostic unit 7 which is configured to carry out the method described below and illustrated in FIG. 2:
• ... x n of the process and stored for further review in the data store For example, 100 consecutive first differential pressure values x- 1 ... X 0 o can be detected and stored at short notice.
• the 100 differential pressure values are successively written in the memory, preferably the ring buffer.
• the diagnostic unit checks whether the
• Differential pressure measuring arrangement and / or the process is in a state that a
• Diagnosis with regard to the obstruction of a or ggfl. also allows both differential pressure lines.
• ... x n lie in a first range ⁇ ⁇ ⁇ .
• ... x n are at a frequency above a definable frequency H n in the first range ⁇ ⁇ ⁇
• the differential pressure measuring arrangement is in a stable state.
• Both the first range ⁇ ⁇ ⁇ and the fixed frequency H n which must be achieved in order to start from a stable state, can in principle be selected individually, for example by the operator of the differential pressure measuring arrangement.
• the first region ⁇ ⁇ ⁇ is likewise determined with the aid of detected differential pressure values of the process.
• the invention provides that a defined number of second differential pressure values x 0 . , .Xo, n in a stable process, ie a state of the process in which of it
• the second differential pressure values x 0 . , .Xo, n be recorded immediately after commissioning of the differential pressure measuring arrangement. With the help of the specified number of second
• Differential pressure values x 0 . , .xo, n can be a simple standard deviation o (xo, i. .. xo, n ) calculate and thus set the first range.
• the first region may comprise the simple standard deviation, such that the first region is ⁇ (x 0 , i, ... x o, n ) ⁇ o (x 0, ..., x o, n).
• the frequency H n is preferably set to 68%, so that in this case, the diagnostic unit 7 checks whether the first differential pressure values x-
• the diagnosis unit 7 determines that the values of the predetermined number of first differential pressure values x-
• Differential pressure values are completely deleted from the memory so that no historical data regarding the process is stored.
• the diagnosis unit 7 determines that the values of the predetermined number of first differential pressure values x-
• Differential pressure measuring arrangement is in a state that the diagnosis of
• Differential pressure line or the differential pressure lines allows.
• the diagnostic unit 7 in step d) can use a known from the prior art method, which determines the determination of the blockage of a or if necessary. also provides both differential pressure lines.
• the diagnostic unit can perform the method described in the aforementioned German patent application DE 10 2013 1 10 059 A1.
• the diagnostic unit 7 checks whether the process has no significant change and thus also from the process point of view a diagnosis of the differential pressure lines 3 , 5 makes sense.
• the diagnostic unit 7 detects a fixed number of others
• Differential pressure values ⁇ .. ⁇ ' ⁇ and calculates an average of the other Differential pressure values. Subsequently, the diagnostic unit 7 checks whether the mean value ⁇ ( ⁇ ... '' ⁇ ) lies within a defined second range ⁇ ⁇ 3 °.
• This second defined range ⁇ ⁇ 3 o can, for example, by the operator or operator of the
• Differential pressure measuring arrangement are set.
• a default value can be stored in the diagnostic unit, which is used when the operator or
• Differential pressure values x- ⁇ . , .x n is determined.
• the second defined area includes a mean and a three times the standard deviation 3 O, both of which are formed from the first differential pressure values, so that the second defined area ⁇ ( ⁇ ⁇ ⁇ . ⁇ ⁇ ..) ⁇ 3 o (x
• the diagnostic unit returns to step a), if the process has a significant change, the new standard value is the triple standard deviation 3 o (xi ... x n ) of the values of the further differential pressure values xY. .x ' n is deposited.
• ⁇ n within the defined second region ⁇ ⁇ 3 o ( ⁇ ⁇ ⁇ . ⁇ ⁇ ..) (X
• the method described above is preferably carried out during operation of the differential pressure measuring arrangement 1 at regular time intervals by the diagnostic unit 7. The time intervals can vary from process to process.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Health & Medical Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Analytical Chemistry (AREA)
• Biomedical Technology (AREA)
• Measuring Fluid Pressure (AREA)

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• 2016
  • 2016-08-10 DE DE102016114846.6A patent/DE102016114846A1/de not_active Withdrawn
• 2017
  • 2017-07-14 EP EP17739979.7A patent/EP3497420A1/de not_active Withdrawn
  • 2017-07-14 US US16/323,967 patent/US11181432B2/en active Active
  • 2017-07-14 WO PCT/EP2017/067824 patent/WO2018028931A1/de unknown
  • 2017-07-14 CN CN201780047058.3A patent/CN109791085A/zh active Pending

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