Abstract: A method for determining the density of an at least flowable, in particular liquid, specimen with a rheometer, in particular a rotational rheometer, includes providing the rheometer with a first measurement component for receiving the at least flowable, in particular liquid, specimen, and a second measurement component with a known volume to be immersed into the specimen. The first and second measurement components are movable relative to one another. The perpendicular force between the two measurement components is measured after the immersion of the second measurement component into the specimen. The measured perpendicular force corresponds to the buoyancy force acting between the specimen and the second measurement component. The density of the specimen is calculated based on Archimedes' principle by reference to the known volume of the second measurement component and the measured perpendicular force. A rheometer for carrying out the method is also provided.

Abstract: Described is a measuring drive for a measuring instrument, in particular a rheometer. The measuring drive has: i) a motor, ii) a shaft, which is coupled to the motor in such a way that the shaft is drivable by the motor, and iii) an ultrasonic device, which is configured to provide ultrasound to the shaft in such a way that at least a part of the shaft is bearable substantially without contact by the ultrasound. Furthermore, the measuring instrument, a method, and a using are described.

Abstract: A method for determining the sticky point of powder samples includes introducing a sample into a first measuring part, placing a second measuring part above the first measuring part to delimit a sample chamber, using a motor to drive the measuring parts relative to one another, using a force application unit to exert a force on the sample normal to a rotational plane of the measuring parts, using a measuring unit to record a torque or shear stress of the sample between the measuring parts, using a temperature-control unit or oven to apply a temperature profile to the sample while measuring the torque or shear stress, and supplying recorded measured values of the torque or shear stress and the sample temperature at measuring points to an evaluation unit. The evaluation unit determines the sticky point from the measured values of the torque or shear stress and the temperature.

Abstract: Described is a measuring drive for a measuring instrument, in particular a rheometer. The measuring drive has: i) a motor, ii) a shaft, which is coupled to the motor in such a way that the shaft is drivable by the motor, and iii) an ultrasonic device, which is configured to provide ultrasound to the shaft in such a way that at least a part of the shaft is bearable substantially without contact by the ultrasound. Furthermore, the measuring instrument, a method, and a using are described.

Abstract: A method for determining the density of an at least flowable, in particular liquid, specimen with a rheometer, in particular a rotational rheometer, includes providing the rheometer with a first measurement component for receiving the at least flowable, in particular liquid, specimen, and a second measurement component with a known volume to be immersed into the specimen. The first and second measurement components are movable relative to one another. The perpendicular force between the two measurement components is measured after the immersion of the second measurement component into the specimen. The measured perpendicular force corresponds to the buoyancy force acting between the specimen and the second measurement component. The density of the specimen is calculated based on Archimedes' principle by reference to the known volume of the second measurement component and the measured perpendicular force. A rheometer for carrying out the method is also provided.

Abstract: A rotational rheometer for measuring powdery or granular materials has a measuring container for receiving the product to be measured and a cover for the measuring container. A measuring body is held by a measuring shaft. The measuring body and the container are rotatable relative to one another. The measuring shaft is guided through the cover with low friction, or without contact altogether. An evaluation unit is arranged outside the measurement container to evaluate the measured values received by the measuring shaft. To seal the bearing gap or the passage of the measuring shaft in or through the cover in the measuring container, both a fluid seal with a sealing fluid inlet and at least a geometric seal cooperating with the fluid seal are provided as a powder barrier.

Abstract: A rotational rheometer for measuring powdery or granular materials has a measuring container for receiving the product to be measured and a cover for the measuring container. A measuring body is held by a measuring shaft. The measuring body and the container are rotatable relative to one another. The measuring shaft is guided through the cover with low friction, or without contact altogether. An evaluation unit is arranged outside the measurement container to evaluate the measured values received by the measuring shaft. To seal the bearing gap or the passage of the measuring shaft in or through the cover in the measuring container, both a fluid seal with a sealing fluid inlet and at least a geometric seal cooperating with the fluid seal are provided as a powder barrier.