Modular measuring device for measuring a mass flow, a viscosity, a density and/or a variable derived therefrom of a flowable medium, in particular a modular Coriolis flowmeter for preferably pharmaceutical bioprocess applications, comprising: - a measuring tube module designed in particular as a disposable article, the measuring tube module comprising at least one measuring tube (3.1, 3.2) through which a medium can flow, the measuring tube module having a fixing body arrangement attached to the at least one measuring tube; a vibration exciter which is set up to excite the measuring tube to vibrate, in particular comprising an exciter magnet and an exciter coil; at least one component of the vibration exciter, in particular the exciter magnet, being arranged on the measuring tube module; at least one vibration sensor (8.1, 8.2) which is set up to detect the vibrations of the at least one measuring tube (3.1, 3.2), in particular comprising a sensor magnet and a sensor coil, wherein at least one component of the vibration sensor (8.1, 8.2), in particular the sensor magnet, is attached to the measuring tube module; - a carrier module, in particular comprising a receptacle, the sensor coil and the exciter coil, wherein the measuring tube module can be arranged in the receiver of the carrier module, the carrier module having a fixing device, the fixing device having a shaft which is designed to be eccentric at least in sections, the shaft being set up to clamp the measuring tube module in the receptacle by means of the fixing body arrangement and to connect it mechanically releasably to the carrier module, characterized in that the shaft is designed as a camshaft, which is mounted on the carrier module and has at least one cam. - a measuring tube module designed in particular as a disposable article, the measuring tube module comprising at least one measuring tube (3.1, 3.2) through which a medium can flow, the measuring tube module having a fixing body arrangement attached to the at least one measuring tube; a vibration exciter which is set up to excite the measuring tube to vibrate, in particular comprising an exciter magnet and an exciter coil; at least one component of the vibration exciter, in particular the exciter magnet, being arranged on the measuring tube module; at least one vibration sensor (8.1, 8.2) which is set up to detect the vibrations of the at least one measuring tube (3.1, 3.2), in particular comprising a sensor magnet and a sensor coil, wherein at least one component of the vibration sensor (8.1, 8.2), in particular the sensor magnet, is attached to the measuring tube module; the measuring tube module comprising at least one measuring tube (3.1, 3.2) through which a medium can flow, the measuring tube module having a fixing body arrangement attached to the at least one measuring tube; a vibration exciter which is set up to excite the measuring tube to vibrate, in particular comprising an exciter magnet and an exciter coil; at least one component of the vibration exciter, in particular the exciter magnet, being arranged on the measuring tube module; at least one vibration sensor (8.1, 8.2) which is set up to detect the vibrations of the at least one measuring tube (3.1, 3.2), in particular comprising a sensor magnet and a sensor coil, wherein at least one component of the vibration sensor (8.1, 8.2), in particular the sensor magnet, is attached to the measuring tube module; - a carrier module, in particular comprising a receptacle, the sensor coil and the exciter coil, wherein the measuring tube module can be arranged in the receiver of the carrier module, the carrier module having a fixing device, the fixing device having a shaft which is designed to be eccentric at least in sections, the shaft being set up to clamp the measuring tube module in the receptacle by means of the fixing body arrangement and to connect it mechanically releasably to the carrier module, characterized in that the shaft is designed as a camshaft, which is mounted on the carrier module and has at least one cam. wherein the measuring tube module can be arranged in the receiver of the carrier module, the carrier module having a fixing device, the fixing device having a shaft which is designed to be eccentric at least in sections, the shaft being set up to clamp the measuring tube module in the receptacle by means of the fixing body arrangement and to connect it mechanically releasably to the carrier module, characterized in that the shaft is designed as a camshaft, which is mounted on the carrier module and has at least one cam.