Germany-based mechanical engineering company Haag + Zeissler says the automotive industry is planning to increase the present plastic content in electric vehicles by around 25% to enable a necessary saving in vehicle weight.
Metal-based materials for structural parts and subassemblies are also going to be replaced by fibre-reinforced plastics in the future. “The machines and manufacturing processes required for this are subject to constant further development,” says Haag + Zeissler.
An important factor in the melting and forming of plastics is the control of the temperature in extruders and calenders. The rotating screws or rollers are supplied with a heating medium such as water, oil or steam, and rotary joints supply the media to seal the machine elements.
The rotating screws and rollers of many types of machines in the plastics industry are fed with heating or cooling media to guarantee the necessary process temperature.
Haag + Zeissler offers suitable rotary joints for the entire process of manufacturing plastic components. The rotary joints are usually placed at the end of the rotating machine components and form the interface to the stationary pipelines.
The company goes on to explain that there is a rotary seal at the heart of every rotary joint. Its reliability and life span are crucial for the machine operators.
The ISO 9001-compliant rotary seal operates with rotary bellows. It has a hard running surface, which has a micromeandering movement with every revolution, which ensures that the sealing pairing lasts longer.
The benefit of the seal is that unplanned downtimes are avoided, which can become costly if production standstills happen often. In addition to labour and machine repair costs, the restarting of the machine also produces scrap.
Haag + Zeissler adds that the higher procurement cost of a bellows seal pays for itself within a few weeks of operation.
The sealing pairing is combined with the bearing elements in a sealing cartridge and the module can be exchanged with little effort and refurbished. The cartridge system also plays to its strengths in continuously operating production plants, where long operation service is needed and short maintenance times are important.
Haag + Zeissler concludes that it consistently manufactures the rotary joints that incorporate this seal in Germany. The rotary joints are developed in a factory in Hesse, Germany, with the goal of individually optimising the product for the complex requirements of the machine user.