Multi-combination volume metering system

The utility model belongs to the technical field of volume metering, and relates to a multi-combination volume metering system which comprises a sampling pipeline, a pressure metering device, a plurality of fluid switch valves and a plurality of metering tanks with different volumes. Part or all of the metering tanks are communicated with the sampling pipeline through the corresponding fluid switch valves; the sensing end of the pressure metering device is arranged in the sampling pipeline; compared with the prior art, when only small-volume sampling fluid needs to be metered, only the metering tank with the minimum volume is kept to be communicated with the sampling pipeline, communication pipelines of other metering tanks and the sampling pipeline are disconnected through the fluid switching valve, and therefore the maximum fluid volume of the volume metering system is reduced; the change amplitude of the pressure in the sampling pipeline is more obvious, so that the problem that the volume measurement of t