For a wide range of valves, there are also a large number of possible materials. Depending on the fitting, these materials are selected based on standards and/or applications. Factors such as strength, chemical and thermal resistance as well as manufacturing processes play a major role in the choice of material.
Corrosive media call for special fittings which provide suitable surface protection.
For protection against aggressive media such as acids and lyes, highly chemical-resistant fluoroplastic coatings are used. These include PTFE, FEP, E-CTFE, ETFE, or PFA.
This coating is applied to areas that come into contact with the media. Unfortunately, not all parts of a coupling assembly can be coated.In this case highly chemical-resistant materials like nickel-based alloys (e.g. Hastelloy®) are used.
The mechanical properties of parts subject to the greatest dynamic loads are enhanced by a special process which improves the surface hardness, strength and ductility while retaining the corrosion resistance of the original material. This signifi cantly increases the lifetime of the coupling.