Varying requirements on metering systems and manufacturer-specific construction of coating stations have resulted in a variety of rod holder types. Generally, systems feature one or two metering rod diameters. In individual cases, up to five different diameters are possible. This is also the reason for the variety of different rod holders.
Concerning specification, the following three factors are decisive:
- Predefined construction principle
- Rod diameter
Since construction principle and rod diameter are predefined, the material is an important criterion for the properties of the rod holder.
Today, as a rule, Polyurethane (PU) or Polyethylene (PE) are applied; older systems frequently still have rod holders made of rubber.