Method for detecting plugging in a coriolis flow measuring device

A method for detecting complete or partial plugging of a measuring tube of a measuring transducer of vibration-type of a flow measuring device, wherein the measuring transducer is flowed through by a medium and has at least two measuring tubes connected for parallel flow and excitable, during use, to execute mechanical oscillations, comprising the steps of:

• A) supplying, by means of at least one heating element, heat to the medium conveyed in a first measuring tube or removing, by means of at least one cooling element, heat from the medium conveyed in the first measuring tube;
• B) registering temperature by means of at least one temperature sensor, which is thermally coupled to the medium conveyed in the first measuring tube;
• C) determining a first comparison variable, which is characteristic for heat transport by the medium in the first measuring tube, based on the supplying of heat or the removing of heat, and the registering of temperature, and comparing such with a reference variable;
• and
• D) detecting plugging of at least one measuring tube of the measuring transducer, if the first comparison variable deviates from the reference variable by more than a limit value.

A flow measuring device, via which at least one physical measured variable of a medium flowing in a pipeline is determinable- especially mass flow, density and/or viscosity of the medium-wherein the flow measuring device has a measuring transducer of a vibration-type having at least two measuring tubes connected for parallel flow and excitable, during use, to execute mechanical oscillations, comprising:

• at least a first heating element, via which heat is suppliable to the medium conveyed during use in a first measuring tube, or at least a first cooling element, via which heat is removable from medium conveyed during use in a first measuring tube;
• at least a first temperature sensor arranged in the region of the first measuring tube, which is thermally coupled to the medium conveyed during use in the first measuring tube;
• and
• electronics embodied in such a manner that, based on a heat supplying via said at least said first heating element or a heat removing via said first cooling element, as well as on temperature registering by said at least said first temperature sensor, wherein:
• a first comparison variable, which is characteristic for heat transport by the medium in the first measuring tube, is determinable during use;
• and
• the determined first comparison variable is comparable with a reference variable;
• and in such a manner that via said electronics, plugging of at least one measuring tube of the measuring transducer is detectable, if the first comparison variable deviates from the reference variable by more than a limit value.