The bellows is lowered at the start of loading and is stopped when it reaches the tanker inlet. The product flow is then started. The material falls freely through the bellows. The tanker is filled with product. The air content of the tanker is returned through the bellows and then discharged through the air vent. The fill level sensor at the outlet of the bellows monitors the fill level of the product in the tanker and closes when the tank is full. When the loading process is complete, the loading bellows automatically retracts to the upper standby position.