Agricultural machine embracing at least one seed metering device (8) for distributing seeds to a drill furrow (9a) in the ground (9). The seed metering device (8) embraces a seed metering element that by means of a driving device is arranged to transport seeds to one or more seed metering lines (812). The seed metering device (8) comprises a chamber for seeds arranged to be supplied with a positive pressure with the purpose of, by the pressure difference arisen hereby, attaching and transporting seeds at the seed metering element. The seed metering line (812) has an inlet (814) in the chamber, with the purpose of, by said positive pressure, creating an air flow for the transportation of the seeds from the chamber through the seed metering line to the drill furrow (9a). The seed metering line (812) has an outer seed line (816) and an inner seed line (826), where the inner seed line (826) is detachably arranged in the outer seed line (816).
