Abstract: An extruding device for extruding plastic tubing includes an extruder with an outlet and a cooling device connected to the outlet of the extruder. The cooling device has a water-filled chamber and a vacuum tank that is directly connected downstream to the water-filled chamber such that a sealed passage for the plastic tubing between the water-filled chamber and the vacuum tank is provided. The water-filled chamber has a water-filled cooling part and a water-filled measuring part. A water- and vacuum-conveying connection is provided between the measuring part and the vacuum tank. A calibrating sleeve with an inner wall surface is connected within the cooling part and is completely immersed in water for cooling purposes. The calibrating sleeve pulls the extruded plastic tubing against its inner wall surface. A measuring device for measuring the wall thickness of the plastic tubing is connected with the measuring part.