A bellow actuator is a rubber below mounted between a steel plate on top and below. The Steel plates and the rubber below build a hermetical air volume. If the steel plates are flanged an adapter plate made of plastic is fixed on top of the upper steel plate to guide the air inlet sideward. If the rubber below is connected to the steel plates by a bead ring the air inlet is guided throw the top steel plate sideward. In both cases the top plate has four holes to fix the air spring. The types –DS and -MB are equipped with bump stops used as limiting end stop or to rest the test rig. Hence the rubber bellow has very good dynamic characteristics as well as good chemical resistance. Air Springs Type BZ can be used in a wide range of temperature (-60°C – 60°C).

Air springs type BZ are available with plates made of stainless steel, an extended range of temperature and or extended chemical resistance against oils and fuels.